Total synthesis of VM55599. Utilization of an intramolecular Diels - Alder cycloaddition of potential biogenetic relevance

Journal of the American Chemical Society

Volumn 122, Issue 8, 2000, Pages 1675-1683

  Stocking, Emily M ^a   Sanz Cervera, Juan F ^b   Williams, Robert M ^a  

^a Department of Environmental and Radiological Health Sciences   (United States)

^b UNIVERSITY OF VALENCIA   (Spain)

Author keywords

[No Author keywords available]

Indexed keywords

PARAHERQUAMIDE DERIVATIVE; UNCLASSIFIED DRUG; VM 55599;

ARTICLE; DRUG ISOLATION; DRUG STRUCTURE; DRUG SYNTHESIS; ISOLATION PROCEDURE; NONHUMAN; PENICILLIUM; REACTION ANALYSIS;

EID: 0034052955     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja993791h     Document Type: Article

References (79)

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30. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
31. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
32. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
33. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
34. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
35. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
36. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
37. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
38. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
39. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
40. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
41. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
42. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
43. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
44. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
45. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
46. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
47. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta
48. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
49. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
50. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
51. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
52. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
53. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
54. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
55. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
56. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
57. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
58. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
59. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
60. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
61. For reviews on biosynthetic Diels-Alder reactions, see: (a) Tarasow, T. M.; Eaton, B. E. CMLS Cell Mol. Life Sci. 1999, 1463 (b) Laschat, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 289. (c) Stipanovic, R. D. Environ. Sci. Res. 1992, 44, 319. For specific references on Diels-Alder reactions proposed in natural products biosynthesis, see: (d) catharanthin: Scott, A. I. Acc. Chem. Res. 1970, 3, 151. (e) Ikarugamycin: Ito, S.; Hirata, Y. Tetrahedron Lett. 1972, 25, 2557. (f) Cytochalasans: Binder, M.; Tamm, C. Angew. Chem., Int. Ed. Engl. 1973, 12, 370. (g) Ircinianin: Hofheinz, W.; Schonholzer, P. Helv. Chim. Acta 1977, 60, 1367. (h) lachananthocarpone: Bazan, A. C.; Edwards, J. M., Weiss, U. Tetrahedron 1978, 34, 3005. (i) Endiandric acids: Bandaranayake, W. M.; Banfield, J. E., Black, D. S. C. J. Chem. Soc., Chem. Commun. 1980, 902. (j) Antibiotic X-14547A: Roush, W. R.; Peseckis, S. M.; Walts, A. E. J. Org. Chem. 1984, 49, 3429. (k) Mevinolin: Moore, R. N.; Bigam, G.; Chan, J. K.; Hogg, A. M. Nakashima, T. T.; Vederas, J. C. J. Am. Chem. Soc. 1985, 107, 3694. Witter, D. J.; Vederas, J. C. J. Org. Chem. 1996, 61, 2613. Kennedy, J.; Auclair, K.; Kendrew, S. G.; Park, C.; Vederas, J. C.; Hutchinson, C. R. Science 1999, 284, 1368. (l) Bishordeninyl terpenes: Schroeder, D. R.; Stermitz, F. R. Tetrahedron 1985, 41, 4309. (m) Coumarins: Dreyer, D. L. Recent Adv. Phytochem. 1986, 20, 317 (n) Betaenone B: Harrison, P. H. M.; Cane, D. E. Chemtracts: Org. Chem. 1988, 1, 369. (0) Sordaricin: Wu, X.; Kato, N.; Takeshita, H. Tennen Yuki Kagobutsu Toronkai Koen Yoshishu 1988, 30, 424. (p) Esperamicins: Schreiber, S. L.; Kiessling, L. L. J. Am. Chem. Soc. 1988, 110, 631. (q) Solanapyrone A: Oikawa, H.; Yokota, T.; Abe, T.; Ichihara, A.; Sakamura, S.; Yoshizawa, Y.; Vederas, J. C. J. Chem. Soc., Chem. Commun. 1989, 1282 and Oikawa, H.; Suzuki, Y.; Katayama, K.; Naya, A.; Chiaki, S.; Ichihara, A. J. Chem. Soc., Perkin Trans 1 1999, 1225 and references therein. (r) Kuwanon J and chalcomoracin: Hano, Y. Nomura, T.; Ueda, S. Chem. Pharm. Bull. 1989, 37, 554. Hano, Y.; Nomura, T.; Ueda, S. Heterocycles 1999, 51, 231. (s) Plagiospirolides C, D and E: Spoerle, J.; Becker, H.; Gupta, M. P.; Veith, M.; Huch, V. Tetrahedron 1989, 45, 5003. (t) Eudesmanolides: Marco, J. A.; Sanz, J. F.; Falco, E. Tetrahedron 1990, 46, 7941. Manzamines: Baldwin, J. E.; Whitehead, R. C. Tetrahedron Lett. 1992, 33, 2059. Baldwin, J. E. et al. Angew. Chem., Int. Ed. 1998, 37, 2661 and references therein. (u) Theonellastreone and conicasterone: Kobayashi, M.; Kawazoe, K., Katori, T.; Kitagawa, I. Chem. Pharm. Bull. 1992, 40, 1773. (v) Nargenicin: Cane, D. E.; Yang, C.-C. J. Am. Chem. Soc. 1984, 106, 784. Cane, D. E.; Tan, W.; Ott, W. R. J. Am. Chem. Soc. 1993, 115, 527. (w) Torreyanic acid: Lee, J. C.; Strobel, G. A.; Lobovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232. Cochleamycins: Shindo, K.; Sakakibara, M.; Kawai, H.; Seto, H. J. Antibiot. 1996, 49, 249. (y) Wistarin: Fontana, A.; Fakhr, I.; Mollo, E.; Cimino, G. Tetrahedron: Asymmetry 1999, 10, 3869. (z) bisorbicillinol: Nicolaou, K. C.; Simonsen, K. B.; Vassilikogiannakis, G.; Baran, P. S.; Vidali, V. P.; Pitsinos, E. N.; Couladouros, E. A. Angew. Chem., Int. Ed. 1999, 38, 3555 and references therein.
62. The synlanti relationship refers to the relative stereochemistry between the C-20 stereogenic center (VM55599 numbering) and the cyclic amino acid residue (proline, β-methylproline, or pipecolic acid): (FORMULA PRESENTED)
63. Williams, R. M.; Kwast, E.; Coffman, H,; Glinka, T. J. Am. Chem. Soc. 1989, 111, 3064.
64. Domingo, L. R.; Sanz-Cervera, J. F.; Williams, R. M.; Picher, M. T.; Marco, J. A. J. Org. Chem. 1997, 62, 1662.
65. (a) Williams, R. M.; Sanz-Cervera, J. F.; Sancenon, F., Marco, J. A.; Halligan, K. J. Am. Chem. Soc. 1998, 120, 1090.
66. (b) Williams, R. M.; Sanz-Cervera, J. F.; Sancenon, F., Marco, J. A.; Halligan, K. Bioorg. Med. Chem. 1998, 6, 1233.
67. This substance was prepared according to ref 6d.
68. (a) Kametani, T.; Kanaya, N.; Ihara, M. J. Chem. Soc., Perkin Trans 1 1981, 959.
69. (b) Somei, M.; Karasawa, Y.; Kaneko, C. Heterocycles 1981, 16, 941.
70. BOP = (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (purchased from Aldrich Chemical Co.).
71. Complete NOE data on cycloadducts 12-15 can be found in Supporting Information.
72. We thank Prof. Tohru Fukuyama for suggesting the use of excess DIBAH for this transformation; see Fukuyama, T.; Liu, G. Pure Appl. Chem. 1997, 69, 501.
73. Conditions for the conversion of compounds 13-15 to the VM55599 diasteromers 19, 21, and 24 were not optimized.
74. Banks, R. M.; Blanchflower, S. E.; Everett, J. R.; Manger, B. R.; Reading, C. J. Antibiot. 1997, 50, 840.
75. Stocking, E.; Sanz-Cervera, J. F.; Williams, R. M.; Unkefer, C. J. J. Am. Chem. Soc. 1996, 118, 7008.
76. Our own work with Penicillium sp. IMI 332995 provided ca. 0.5 mg of VM55599 and ∼250 mg of paraherquamide A(∼1:500 ratio) from 12 L of surface culture media.
77. For relevant work, see (a) Dunkerton, L. V.; Chen, H.; McKillican, B. P. Tetrahedron Lett. 1988, 29, 2539. (b) Fabre, J. L.; Farge, D.; James, C.; Lave, D. Tetrahedron Lett. 1985, 26, 5447.
78. For relevant work, see (a) Dunkerton, L. V.; Chen, H.; McKillican, B. P. Tetrahedron Lett. 1988, 29, 2539. (b) Fabre, J. L.; Farge, D.; James, C.; Lave, D. Tetrahedron Lett. 1985, 26, 5447.
79. For an analogous system, see Oikawa, H.; Katayama, K.; Suzuki, Y.; Ichihara, A. J. Chem. Soc., Chem. Commun. 1995, 1321.