Stereoselective preparation of Syn α-hydroxy-β-amino ester units via regioselective opening of α,β-epoxy esters: Enantioselective synthesis of taxol C-13 side chain and cyclohexylnorstatine

Journal of Organic Chemistry

Volumn 61, Issue 10, 1996, Pages 3557-3560

  Righi, Giuliana ^a   Rumboldt, Giovanna ^a   Bonini, Carlo ^b  

^a SAPIENZA UNIVERSITY OF ROME   (Italy)

^b UNIVERSITY OF BASILICATA   (Italy)

Author keywords

[No Author keywords available]

Indexed keywords

AMINO ACID DERIVATIVE; CYCLOHEXYLNORSTATINE; PACLITAXEL; STATINE DERIVATIVE;

ARTICLE; CHIRALITY; DRUG SYNTHESIS; REACTION ANALYSIS;

EID: 0029940233     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo951441h     Document Type: Article

References (47)

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2. Kingston, D. G. I. Pharmacol. Ther. 1991, 52, 1. Swindell, C. S. Org. Prep. Proc. Int. 1991, 23, 465. Bormann, S. Chem. Eng. News 1991, 69 (35), 11; 1992, 70 (41), 30. Potier, P., Guènard, D.; Guèritte-Voegelein, F. Acc. Chem. Res. 1993, 26, 160. Lavelle, F.; Guèritte-Voegelein, F.; Guènard, D. Bull. Cancer 1993, 80, 326. Kingston, D. G. I.; Molinero, A. A.; Rimoldi, J. M. Prog. Chem. Org. Nat. Prod. 1993, 61, Suffhess, L. M. In Annual Reports in Medicinal Chemistry; Bristol, J. A., Ed.; Academic Press: San Diego, 1993; Vol. 28, pp 305-314. Nicolaou, K. C.; Dai, W-M.; Guy, R. K. Angew. Chem., Int. Ed. Engl. 1994, 33, 15.
3. Kingston, D. G. I. Pharmacol. Ther. 1991, 52, 1. Swindell, C. S. Org. Prep. Proc. Int. 1991, 23, 465. Bormann, S. Chem. Eng. News 1991, 69 (35), 11; 1992, 70 (41), 30. Potier, P., Guènard, D.; Guèritte-Voegelein, F. Acc. Chem. Res. 1993, 26, 160. Lavelle, F.; Guèritte-Voegelein, F.; Guènard, D. Bull. Cancer 1993, 80, 326. Kingston, D. G. I.; Molinero, A. A.; Rimoldi, J. M. Prog. Chem. Org. Nat. Prod. 1993, 61, Suffhess, L. M. In Annual Reports in Medicinal Chemistry; Bristol, J. A., Ed.; Academic Press: San Diego, 1993; Vol. 28, pp 305-314. Nicolaou, K. C.; Dai, W-M.; Guy, R. K. Angew. Chem., Int. Ed. Engl. 1994, 33, 15.
4. Kingston, D. G. I. Pharmacol. Ther. 1991, 52, 1. Swindell, C. S. Org. Prep. Proc. Int. 1991, 23, 465. Bormann, S. Chem. Eng. News 1991, 69 (35), 11; 1992, 70 (41), 30. Potier, P., Guènard, D.; Guèritte-Voegelein, F. Acc. Chem. Res. 1993, 26, 160. Lavelle, F.; Guèritte-Voegelein, F.; Guènard, D. Bull. Cancer 1993, 80, 326. Kingston, D. G. I.; Molinero, A. A.; Rimoldi, J. M. Prog. Chem. Org. Nat. Prod. 1993, 61, Suffhess, L. M. In Annual Reports in Medicinal Chemistry; Bristol, J. A., Ed.; Academic Press: San Diego, 1993; Vol. 28, pp 305-314. Nicolaou, K. C.; Dai, W-M.; Guy, R. K. Angew. Chem., Int. Ed. Engl. 1994, 33, 15.
5. Kingston, D. G. I. Pharmacol. Ther. 1991, 52, 1. Swindell, C. S. Org. Prep. Proc. Int. 1991, 23, 465. Bormann, S. Chem. Eng. News 1991, 69 (35), 11; 1992, 70 (41), 30. Potier, P., Guènard, D.; Guèritte-Voegelein, F. Acc. Chem. Res. 1993, 26, 160. Lavelle, F.; Guèritte-Voegelein, F.; Guènard, D. Bull. Cancer 1993, 80, 326. Kingston, D. G. I.; Molinero, A. A.; Rimoldi, J. M. Prog. Chem. Org. Nat. Prod. 1993, 61, Suffhess, L. M. In Annual Reports in Medicinal Chemistry; Bristol, J. A., Ed.; Academic Press: San Diego, 1993; Vol. 28, pp 305-314. Nicolaou, K. C.; Dai, W-M.; Guy, R. K. Angew. Chem., Int. Ed. Engl. 1994, 33, 15.
6. Kingston, D. G. I. Pharmacol. Ther. 1991, 52, 1. Swindell, C. S. Org. Prep. Proc. Int. 1991, 23, 465. Bormann, S. Chem. Eng. News 1991, 69 (35), 11; 1992, 70 (41), 30. Potier, P., Guènard, D.; Guèritte-Voegelein, F. Acc. Chem. Res. 1993, 26, 160. Lavelle, F.; Guèritte-Voegelein, F.; Guènard, D. Bull. Cancer 1993, 80, 326. Kingston, D. G. I.; Molinero, A. A.; Rimoldi, J. M. Prog. Chem. Org. Nat. Prod. 1993, 61, Suffhess, L. M. In Annual Reports in Medicinal Chemistry; Bristol, J. A., Ed.; Academic Press: San Diego, 1993; Vol. 28, pp 305-314. Nicolaou, K. C.; Dai, W-M.; Guy, R. K. Angew. Chem., Int. Ed. Engl. 1994, 33, 15.
7. Kingston, D. G. I. Pharmacol. Ther. 1991, 52, 1. Swindell, C. S. Org. Prep. Proc. Int. 1991, 23, 465. Bormann, S. Chem. Eng. News 1991, 69 (35), 11; 1992, 70 (41), 30. Potier, P., Guènard, D.; Guèritte-Voegelein, F. Acc. Chem. Res. 1993, 26, 160. Lavelle, F.; Guèritte-Voegelein, F.; Guènard, D. Bull. Cancer 1993, 80, 326. Kingston, D. G. I.; Molinero, A. A.; Rimoldi, J. M. Prog. Chem. Org. Nat. Prod. 1993, 61, Suffhess, L. M. In Annual Reports in Medicinal Chemistry; Bristol, J. A., Ed.; Academic Press: San Diego, 1993; Vol. 28, pp 305-314. Nicolaou, K. C.; Dai, W-M.; Guy, R. K. Angew. Chem., Int. Ed. Engl. 1994, 33, 15.
8. Kingston, D. G. I. Pharmacol. Ther. 1991, 52, 1. Swindell, C. S. Org. Prep. Proc. Int. 1991, 23, 465. Bormann, S. Chem. Eng. News 1991, 69 (35), 11; 1992, 70 (41), 30. Potier, P., Guènard, D.; Guèritte-Voegelein, F. Acc. Chem. Res. 1993, 26, 160. Lavelle, F.; Guèritte-Voegelein, F.; Guènard, D. Bull. Cancer 1993, 80, 326. Kingston, D. G. I.; Molinero, A. A.; Rimoldi, J. M. Prog. Chem. Org. Nat. Prod. 1993, 61, Suffhess, L. M. In Annual Reports in Medicinal Chemistry; Bristol, J. A., Ed.; Academic Press: San Diego, 1993; Vol. 28, pp 305-314. Nicolaou, K. C.; Dai, W-M.; Guy, R. K. Angew. Chem., Int. Ed. Engl. 1994, 33, 15.
9. Kingston, D. G. I. Pharmacol. Ther. 1991, 52, 1. Swindell, C. S. Org. Prep. Proc. Int. 1991, 23, 465. Bormann, S. Chem. Eng. News 1991, 69 (35), 11; 1992, 70 (41), 30. Potier, P., Guènard, D.; Guèritte-Voegelein, F. Acc. Chem. Res. 1993, 26, 160. Lavelle, F.; Guèritte-Voegelein, F.; Guènard, D. Bull. Cancer 1993, 80, 326. Kingston, D. G. I.; Molinero, A. A.; Rimoldi, J. M. Prog. Chem. Org. Nat. Prod. 1993, 61, Suffhess, L. M. In Annual Reports in Medicinal Chemistry; Bristol, J. A., Ed.; Academic Press: San Diego, 1993; Vol. 28, pp 305-314. Nicolaou, K. C.; Dai, W-M.; Guy, R. K. Angew. Chem., Int. Ed. Engl. 1994, 33, 15.
10. Kingston, D. G. I. Pharmacol. Ther. 1991, 52, 1. Swindell, C. S. Org. Prep. Proc. Int. 1991, 23, 465. Bormann, S. Chem. Eng. News 1991, 69 (35), 11; 1992, 70 (41), 30. Potier, P., Guènard, D.; Guèritte-Voegelein, F. Acc. Chem. Res. 1993, 26, 160. Lavelle, F.; Guèritte-Voegelein, F.; Guènard, D. Bull. Cancer 1993, 80, 326. Kingston, D. G. I.; Molinero, A. A.; Rimoldi, J. M. Prog. Chem. Org. Nat. Prod. 1993, 61, Suffhess, L. M. In Annual Reports in Medicinal Chemistry; Bristol, J. A., Ed.; Academic Press: San Diego, 1993; Vol. 28, pp 305-314. Nicolaou, K. C.; Dai, W-M.; Guy, R. K. Angew. Chem., Int. Ed. Engl. 1994, 33, 15.
11. Wani, M. C.; Taylor, H. L.; Wall, M. E.; Coggon, P.; McPhail, A. T. J. Am. Chem. Soc. 1971, 93, 2325. Rowinsky, E. K.; Cazenave, L. A.; Nonehower, R. C. J. Natl. Cancer Inst. 1990, 82, 1247. Mathew, A. E.; Mejillano, M. R.; Nath, J. P.; Himes, R. H.; Stella, V. J. J. Med. Chem. 1992, 35, 145.
12. Wani, M. C.; Taylor, H. L.; Wall, M. E.; Coggon, P.; McPhail, A. T. J. Am. Chem. Soc. 1971, 93, 2325. Rowinsky, E. K.; Cazenave, L. A.; Nonehower, R. C. J. Natl. Cancer Inst. 1990, 82, 1247. Mathew, A. E.; Mejillano, M. R.; Nath, J. P.; Himes, R. H.; Stella, V. J. J. Med. Chem. 1992, 35, 145.
13. Wani, M. C.; Taylor, H. L.; Wall, M. E.; Coggon, P.; McPhail, A. T. J. Am. Chem. Soc. 1971, 93, 2325. Rowinsky, E. K.; Cazenave, L. A.; Nonehower, R. C. J. Natl. Cancer Inst. 1990, 82, 1247. Mathew, A. E.; Mejillano, M. R.; Nath, J. P.; Himes, R. H.; Stella, V. J. J. Med. Chem. 1992, 35, 145.
14. Iizuka, K.; Kamijo, T.; Harada, H.; Ahakane, K.; Umeyama, H.; Ishida, T.; Kiso, Y. J. Med. Chem. 1990, 33, 2707.
15. For amine opening, see. (a) Chong, J. M.; Sharpless, K. B. J. Org. Chem. 1985, 50, 1560. For azide opening, see: (b) Behrens, C. H.; Sharpless, K. B. J. Org. Chem. 1985, 50, 5696
16. For amine opening, see. (a) Chong, J. M.; Sharpless, K. B. J. Org. Chem. 1985, 50, 1560. For azide opening, see: (b) Behrens, C. H.; Sharpless, K. B. J. Org. Chem. 1985, 50, 5696
17. Gao, Y ; Hanson, R. M.; Klunder, J. M.; Ko, S. Y.; Masamune, H.; Sharpless, K. B. J. Am. Chem. Soc. 1987, 109, 5765.
18. For a complete overview of the reaction, see: Jacobsen, E. N. In Catalytic Asymmetric Synthesis; Ojima, I., Ed.; VCH Publishers, Inc.: New York, 1993; p 159.
19. One of the most successful application of the Jacobsen epoxidation on unsaturated cis esters has led to a simple and direct synthesis of the taxol C-13 side chain: Deng, L.; Jacobsen, E. N. J. Org. Chem. 1992, 57, 4320.
20. Chong, J. M.; Sharpless, K. B. Tetrahedron Lett. 1985, 26, 4683 and references therein.
21. See review: Bonini, C.; Righi, G. Synthesis 1994, 225.
22. (a) Otsubo, K.; Inanaga, J.; Yamaguchi, M. Tetrahedron Lett. 1987, 38, 4435.
23. (b) Bonini, C.; Righi, G.; Sotgiu, G. J. Org. Chem. 1991, 56, 6206. Bonini, C.; Righi, G. Tetrahedron 1992, 48, 1531.
24. (b) Bonini, C.; Righi, G.; Sotgiu, G. J. Org. Chem. 1991, 56, 6206. Bonini, C.; Righi, G. Tetrahedron 1992, 48, 1531.
25. (a) Bonini, C.; Giuliano, C.; Righi, G.; Rossi, L. Synth. Commun. 1992, 22, 1863.
26. (b) Federici, C.; Righi, G., Rossi, L.; Bonini, C.; Chiummientu, L.; Funicello, M. Tetrahedron Lett. 1994, 35, 797. These papers reported the use of LiI with Amberlyst 15 in the regioselective C-3 oxirane opening of 2,3-epoxy alcohols and derivatives. The application of the reported conditions on 2,3-epoxy esters did not give consistent results. More interestingly, the use of NaI and NaBr in acetone afforded 2-halo-3-hydroxy esters: Righi, G.; Rumboldt, G.; Bonini, C. Tetrahedron 1995, 51, 13401.
27. (b) Federici, C.; Righi, G., Rossi, L.; Bonini, C.; Chiummientu, L.; Funicello, M. Tetrahedron Lett. 1994, 35, 797. These papers reported the use of LiI with Amberlyst 15 in the regioselective C-3 oxirane opening of 2,3-epoxy alcohols and derivatives. The application of the reported conditions on 2,3-epoxy esters did not give consistent results. More interestingly, the use of NaI and NaBr in acetone afforded 2-halo-3-hydroxy esters: Righi, G.; Rumboldt, G.; Bonini, C. Tetrahedron 1995, 51, 13401.
28. Hiang, D.-F. Huang, L. Tetrahedron 1990, 46, 3135.
29. Bonini, C.; Righi, G. J. Chem. Soc., Chem. Commun. 1994, 2767.
30. 1H-NMR spectra the acetyl group in C-3 position (β to the carboxyl group) always resonates at 2.01-2.03 ppm; on the contrary the acetyl group in C-2 position resonates downfield at 2.16-2.18 ppm.
31. 1-like pathway or from "self-displacement" by adventitious iodide ion. The lower reactivity of the bromo alcohol results in longer reaction times but in a complete, stereoselective displacement of the bromine by azide ion: Bonini, C.; Righi, G., unpublished results.
32. For some of the most recent taxol C-13 side chain syntheses, see: (a) Denis, J. N.; Greene, A. E.; Serra, A. A.; Luche, M. J. J. Org. Chem. 1986, 51, 46. (b) Honig, H.; Seufer-Wasserthal, P.; Weber, H. Tetrahedron 1990, 46, 3841. (c) Denis, J. N.; Carrea, A.; Greene, A. E. J. Org. Chem. 1990, 55, 1957. (d) Ojima, I.; Habus, I.; Zhao, M.; Georg, G. I.; Jayasinge, L. R. J. Org. Chem. 1991, 56, 1681. (e) Denis, J. N.; Carrea; A.; Greene, A. E. J. Org. Chem. 1991, 56, 6939 (f) Bunnage, M. E.; Davies, S. G.; Goodwin, C. J. J. Chem. Soc., Perkin Trans. 1 1993, 1375. (g) Gou, D.-M.; Liu, Y.-C.; Chen, C.-S. J. Org. Chem. 1993, 58, 1287. (h) Koskinen, Ari, M. P.; Karvinen, E. K.; Siirila, J. P. J. Chem. Soc., Chem. Commun. 1994, 21. (i) Kearnes, J.; Kayser, M. M. Tetrahedron Lett. 1994, 35, 2845. (j) Wang, Z.; Kolb, H. C.; Sharpless, K. B. J. Org. Chem. 1994, 59, 5104. (k) Dondoni, A.; Parroni, D.; Semola, T. Synthesis 1995, 187.
33. For some of the most recent taxol C-13 side chain syntheses, see: (a) Denis, J. N.; Greene, A. E.; Serra, A. A.; Luche, M. J. J. Org. Chem. 1986, 51, 46. (b) Honig, H.; Seufer-Wasserthal, P.; Weber, H. Tetrahedron 1990, 46, 3841. (c) Denis, J. N.; Carrea, A.; Greene, A. E. J. Org. Chem. 1990, 55, 1957. (d) Ojima, I.; Habus, I.; Zhao, M.; Georg, G. I.; Jayasinge, L. R. J. Org. Chem. 1991, 56, 1681. (e) Denis, J. N.; Carrea; A.; Greene, A. E. J. Org. Chem. 1991, 56, 6939 (f) Bunnage, M. E.; Davies, S. G.; Goodwin, C. J. J. Chem. Soc., Perkin Trans. 1 1993, 1375. (g) Gou, D.-M.; Liu, Y.-C.; Chen, C.-S. J. Org. Chem. 1993, 58, 1287. (h) Koskinen, Ari, M. P.; Karvinen, E. K.; Siirila, J. P. J. Chem. Soc., Chem. Commun. 1994, 21. (i) Kearnes, J.; Kayser, M. M. Tetrahedron Lett. 1994, 35, 2845. (j) Wang, Z.; Kolb, H. C.; Sharpless, K. B. J. Org. Chem. 1994, 59, 5104. (k) Dondoni, A.; Parroni, D.; Semola, T. Synthesis 1995, 187.
34. For some of the most recent taxol C-13 side chain syntheses, see: (a) Denis, J. N.; Greene, A. E.; Serra, A. A.; Luche, M. J. J. Org. Chem. 1986, 51, 46. (b) Honig, H.; Seufer-Wasserthal, P.; Weber, H. Tetrahedron 1990, 46, 3841. (c) Denis, J. N.; Carrea, A.; Greene, A. E. J. Org. Chem. 1990, 55, 1957. (d) Ojima, I.; Habus, I.; Zhao, M.; Georg, G. I.; Jayasinge, L. R. J. Org. Chem. 1991, 56, 1681. (e) Denis, J. N.; Carrea; A.; Greene, A. E. J. Org. Chem. 1991, 56, 6939 (f) Bunnage, M. E.; Davies, S. G.; Goodwin, C. J. J. Chem. Soc., Perkin Trans. 1 1993, 1375. (g) Gou, D.-M.; Liu, Y.-C.; Chen, C.-S. J. Org. Chem. 1993, 58, 1287. (h) Koskinen, Ari, M. P.; Karvinen, E. K.; Siirila, J. P. J. Chem. Soc., Chem. Commun. 1994, 21. (i) Kearnes, J.; Kayser, M. M. Tetrahedron Lett. 1994, 35, 2845. (j) Wang, Z.; Kolb, H. C.; Sharpless, K. B. J. Org. Chem. 1994, 59, 5104. (k) Dondoni, A.; Parroni, D.; Semola, T. Synthesis 1995, 187.
35. For some of the most recent taxol C-13 side chain syntheses, see: (a) Denis, J. N.; Greene, A. E.; Serra, A. A.; Luche, M. J. J. Org. Chem. 1986, 51, 46. (b) Honig, H.; Seufer-Wasserthal, P.; Weber, H. Tetrahedron 1990, 46, 3841. (c) Denis, J. N.; Carrea, A.; Greene, A. E. J. Org. Chem. 1990, 55, 1957. (d) Ojima, I.; Habus, I.; Zhao, M.; Georg, G. I.; Jayasinge, L. R. J. Org. Chem. 1991, 56, 1681. (e) Denis, J. N.; Carrea; A.; Greene, A. E. J. Org. Chem. 1991, 56, 6939 (f) Bunnage, M. E.; Davies, S. G.; Goodwin, C. J. J. Chem. Soc., Perkin Trans. 1 1993, 1375. (g) Gou, D.-M.; Liu, Y.-C.; Chen, C.-S. J. Org. Chem. 1993, 58, 1287. (h) Koskinen, Ari, M. P.; Karvinen, E. K.; Siirila, J. P. J. Chem. Soc., Chem. Commun. 1994, 21. (i) Kearnes, J.; Kayser, M. M. Tetrahedron Lett. 1994, 35, 2845. (j) Wang, Z.; Kolb, H. C.; Sharpless, K. B. J. Org. Chem. 1994, 59, 5104. (k) Dondoni, A.; Parroni, D.; Semola, T. Synthesis 1995, 187.
36. For some of the most recent taxol C-13 side chain syntheses, see: (a) Denis, J. N.; Greene, A. E.; Serra, A. A.; Luche, M. J. J. Org. Chem. 1986, 51, 46. (b) Honig, H.; Seufer-Wasserthal, P.; Weber, H. Tetrahedron 1990, 46, 3841. (c) Denis, J. N.; Carrea, A.; Greene, A. E. J. Org. Chem. 1990, 55, 1957. (d) Ojima, I.; Habus, I.; Zhao, M.; Georg, G. I.; Jayasinge, L. R. J. Org. Chem. 1991, 56, 1681. (e) Denis, J. N.; Carrea; A.; Greene, A. E. J. Org. Chem. 1991, 56, 6939 (f) Bunnage, M. E.; Davies, S. G.; Goodwin, C. J. J. Chem. Soc., Perkin Trans. 1 1993, 1375. (g) Gou, D.-M.; Liu, Y.-C.; Chen, C.-S. J. Org. Chem. 1993, 58, 1287. (h) Koskinen, Ari, M. P.; Karvinen, E. K.; Siirila, J. P. J. Chem. Soc., Chem. Commun. 1994, 21. (i) Kearnes, J.; Kayser, M. M. Tetrahedron Lett. 1994, 35, 2845. (j) Wang, Z.; Kolb, H. C.; Sharpless, K. B. J. Org. Chem. 1994, 59, 5104. (k) Dondoni, A.; Parroni, D.; Semola, T. Synthesis 1995, 187.
37. For some of the most recent taxol C-13 side chain syntheses, see: (a) Denis, J. N.; Greene, A. E.; Serra, A. A.; Luche, M. J. J. Org. Chem. 1986, 51, 46. (b) Honig, H.; Seufer-Wasserthal, P.; Weber, H. Tetrahedron 1990, 46, 3841. (c) Denis, J. N.; Carrea, A.; Greene, A. E. J. Org. Chem. 1990, 55, 1957. (d) Ojima, I.; Habus, I.; Zhao, M.; Georg, G. I.; Jayasinge, L. R. J. Org. Chem. 1991, 56, 1681. (e) Denis, J. N.; Carrea; A.; Greene, A. E. J. Org. Chem. 1991, 56, 6939 (f) Bunnage, M. E.; Davies, S. G.; Goodwin, C. J. J. Chem. Soc., Perkin Trans. 1 1993, 1375. (g) Gou, D.-M.; Liu, Y.-C.; Chen, C.-S. J. Org. Chem. 1993, 58, 1287. (h) Koskinen, Ari, M. P.; Karvinen, E. K.; Siirila, J. P. J. Chem. Soc., Chem. Commun. 1994, 21. (i) Kearnes, J.; Kayser, M. M. Tetrahedron Lett. 1994, 35, 2845. (j) Wang, Z.; Kolb, H. C.; Sharpless, K. B. J. Org. Chem. 1994, 59, 5104. (k) Dondoni, A.; Parroni, D.; Semola, T. Synthesis 1995, 187.
38. For some of the most recent taxol C-13 side chain syntheses, see: (a) Denis, J. N.; Greene, A. E.; Serra, A. A.; Luche, M. J. J. Org. Chem. 1986, 51, 46. (b) Honig, H.; Seufer-Wasserthal, P.; Weber, H. Tetrahedron 1990, 46, 3841. (c) Denis, J. N.; Carrea, A.; Greene, A. E. J. Org. Chem. 1990, 55, 1957. (d) Ojima, I.; Habus, I.; Zhao, M.; Georg, G. I.; Jayasinge, L. R. J. Org. Chem. 1991, 56, 1681. (e) Denis, J. N.; Carrea; A.; Greene, A. E. J. Org. Chem. 1991, 56, 6939 (f) Bunnage, M. E.; Davies, S. G.; Goodwin, C. J. J. Chem. Soc., Perkin Trans. 1 1993, 1375. (g) Gou, D.-M.; Liu, Y.-C.; Chen, C.-S. J. Org. Chem. 1993, 58, 1287. (h) Koskinen, Ari, M. P.; Karvinen, E. K.; Siirila, J. P. J. Chem. Soc., Chem. Commun. 1994, 21. (i) Kearnes, J.; Kayser, M. M. Tetrahedron Lett. 1994, 35, 2845. (j) Wang, Z.; Kolb, H. C.; Sharpless, K. B. J. Org. Chem. 1994, 59, 5104. (k) Dondoni, A.; Parroni, D.; Semola, T. Synthesis 1995, 187.
39. For some of the most recent taxol C-13 side chain syntheses, see: (a) Denis, J. N.; Greene, A. E.; Serra, A. A.; Luche, M. J. J. Org. Chem. 1986, 51, 46. (b) Honig, H.; Seufer-Wasserthal, P.; Weber, H. Tetrahedron 1990, 46, 3841. (c) Denis, J. N.; Carrea, A.; Greene, A. E. J. Org. Chem. 1990, 55, 1957. (d) Ojima, I.; Habus, I.; Zhao, M.; Georg, G. I.; Jayasinge, L. R. J. Org. Chem. 1991, 56, 1681. (e) Denis, J. N.; Carrea; A.; Greene, A. E. J. Org. Chem. 1991, 56, 6939 (f) Bunnage, M. E.; Davies, S. G.; Goodwin, C. J. J. Chem. Soc., Perkin Trans. 1 1993, 1375. (g) Gou, D.-M.; Liu, Y.-C.; Chen, C.-S. J. Org. Chem. 1993, 58, 1287. (h) Koskinen, Ari, M. P.; Karvinen, E. K.; Siirila, J. P. J. Chem. Soc., Chem. Commun. 1994, 21. (i) Kearnes, J.; Kayser, M. M. Tetrahedron Lett. 1994, 35, 2845. (j) Wang, Z.; Kolb, H. C.; Sharpless, K. B. J. Org. Chem. 1994, 59, 5104. (k) Dondoni, A.; Parroni, D.; Semola, T. Synthesis 1995, 187.
40. For some of the most recent taxol C-13 side chain syntheses, see: (a) Denis, J. N.; Greene, A. E.; Serra, A. A.; Luche, M. J. J. Org. Chem. 1986, 51, 46. (b) Honig, H.; Seufer-Wasserthal, P.; Weber, H. Tetrahedron 1990, 46, 3841. (c) Denis, J. N.; Carrea, A.; Greene, A. E. J. Org. Chem. 1990, 55, 1957. (d) Ojima, I.; Habus, I.; Zhao, M.; Georg, G. I.; Jayasinge, L. R. J. Org. Chem. 1991, 56, 1681. (e) Denis, J. N.; Carrea; A.; Greene, A. E. J. Org. Chem. 1991, 56, 6939 (f) Bunnage, M. E.; Davies, S. G.; Goodwin, C. J. J. Chem. Soc., Perkin Trans. 1 1993, 1375. (g) Gou, D.-M.; Liu, Y.-C.; Chen, C.-S. J. Org. Chem. 1993, 58, 1287. (h) Koskinen, Ari, M. P.; Karvinen, E. K.; Siirila, J. P. J. Chem. Soc., Chem. Commun. 1994, 21. (i) Kearnes, J.; Kayser, M. M. Tetrahedron Lett. 1994, 35, 2845. (j) Wang, Z.; Kolb, H. C.; Sharpless, K. B. J. Org. Chem. 1994, 59, 5104. (k) Dondoni, A.; Parroni, D.; Semola, T. Synthesis 1995, 187.
41. For some of the most recent taxol C-13 side chain syntheses, see: (a) Denis, J. N.; Greene, A. E.; Serra, A. A.; Luche, M. J. J. Org. Chem. 1986, 51, 46. (b) Honig, H.; Seufer-Wasserthal, P.; Weber, H. Tetrahedron 1990, 46, 3841. (c) Denis, J. N.; Carrea, A.; Greene, A. E. J. Org. Chem. 1990, 55, 1957. (d) Ojima, I.; Habus, I.; Zhao, M.; Georg, G. I.; Jayasinge, L. R. J. Org. Chem. 1991, 56, 1681. (e) Denis, J. N.; Carrea; A.; Greene, A. E. J. Org. Chem. 1991, 56, 6939 (f) Bunnage, M. E.; Davies, S. G.; Goodwin, C. J. J. Chem. Soc., Perkin Trans. 1 1993, 1375. (g) Gou, D.-M.; Liu, Y.-C.; Chen, C.-S. J. Org. Chem. 1993, 58, 1287. (h) Koskinen, Ari, M. P.; Karvinen, E. K.; Siirila, J. P. J. Chem. Soc., Chem. Commun. 1994, 21. (i) Kearnes, J.; Kayser, M. M. Tetrahedron Lett. 1994, 35, 2845. (j) Wang, Z.; Kolb, H. C.; Sharpless, K. B. J. Org. Chem. 1994, 59, 5104. (k) Dondoni, A.; Parroni, D.; Semola, T. Synthesis 1995, 187.
42. For some of the most recent taxol C-13 side chain syntheses, see: (a) Denis, J. N.; Greene, A. E.; Serra, A. A.; Luche, M. J. J. Org. Chem. 1986, 51, 46. (b) Honig, H.; Seufer-Wasserthal, P.; Weber, H. Tetrahedron 1990, 46, 3841. (c) Denis, J. N.; Carrea, A.; Greene, A. E. J. Org. Chem. 1990, 55, 1957. (d) Ojima, I.; Habus, I.; Zhao, M.; Georg, G. I.; Jayasinge, L. R. J. Org. Chem. 1991, 56, 1681. (e) Denis, J. N.; Carrea; A.; Greene, A. E. J. Org. Chem. 1991, 56, 6939 (f) Bunnage, M. E.; Davies, S. G.; Goodwin, C. J. J. Chem. Soc., Perkin Trans. 1 1993, 1375. (g) Gou, D.-M.; Liu, Y.-C.; Chen, C.-S. J. Org. Chem. 1993, 58, 1287. (h) Koskinen, Ari, M. P.; Karvinen, E. K.; Siirila, J. P. J. Chem. Soc., Chem. Commun. 1994, 21. (i) Kearnes, J.; Kayser, M. M. Tetrahedron Lett. 1994, 35, 2845. (j) Wang, Z.; Kolb, H. C.; Sharpless, K. B. J. Org. Chem. 1994, 59, 5104. (k) Dondoni, A.; Parroni, D.; Semola, T. Synthesis 1995, 187.
43. For recent syntheses of norstatine analogs, see: (a) Iizuka, K.; Kamijo, T.; Harada, H.; Akahane, K.; Kobata, T.; Umeyama, H.; Ishida, T.; Kiso, Y. J. Med. Chem. 1990, 33, 2707. (b) Ojima, I.; Park, Y. H.; Sun, C. M.; Brigaud, T.; Zhao, M. Tetrahedron Lett. 1992, 33, 5737. (c) Kobayashi, Y.; Takemoto, Y.; Kamjio, T.; Harada, H.; Ho, Y.; Terashima, S. Tetrahedron 1992, 48, 1853. (d) Hattori, K.; Yamamoto, H. Tetrahedron 1994, 50, 2785.
44. For recent syntheses of norstatine analogs, see: (a) Iizuka, K.; Kamijo, T.; Harada, H.; Akahane, K.; Kobata, T.; Umeyama, H.; Ishida, T.; Kiso, Y. J. Med. Chem. 1990, 33, 2707. (b) Ojima, I.; Park, Y. H.; Sun, C. M.; Brigaud, T.; Zhao, M. Tetrahedron Lett. 1992, 33, 5737. (c) Kobayashi, Y.; Takemoto, Y.; Kamjio, T.; Harada, H.; Ho, Y.; Terashima, S. Tetrahedron 1992, 48, 1853. (d) Hattori, K.; Yamamoto, H. Tetrahedron 1994, 50, 2785.
45. For recent syntheses of norstatine analogs, see: (a) Iizuka, K.; Kamijo, T.; Harada, H.; Akahane, K.; Kobata, T.; Umeyama, H.; Ishida, T.; Kiso, Y. J. Med. Chem. 1990, 33, 2707. (b) Ojima, I.; Park, Y. H.; Sun, C. M.; Brigaud, T.; Zhao, M. Tetrahedron Lett. 1992, 33, 5737. (c) Kobayashi, Y.; Takemoto, Y.; Kamjio, T.; Harada, H.; Ho, Y.; Terashima, S. Tetrahedron 1992, 48, 1853. (d) Hattori, K.; Yamamoto, H. Tetrahedron 1994, 50, 2785.
46. For recent syntheses of norstatine analogs, see: (a) Iizuka, K.; Kamijo, T.; Harada, H.; Akahane, K.; Kobata, T.; Umeyama, H.; Ishida, T.; Kiso, Y. J. Med. Chem. 1990, 33, 2707. (b) Ojima, I.; Park, Y. H.; Sun, C. M.; Brigaud, T.; Zhao, M. Tetrahedron Lett. 1992, 33, 5737. (c) Kobayashi, Y.; Takemoto, Y.; Kamjio, T.; Harada, H.; Ho, Y.; Terashima, S. Tetrahedron 1992, 48, 1853. (d) Hattori, K.; Yamamoto, H. Tetrahedron 1994, 50, 2785.
47. Legster, J.; Thijs, L.; Zwanenburg, B. Recl. Trav. Chim. Pays-Bas 1992, 111, 1.