Synthesis of a C(1)-C(14)-containing fragment of callipeltoside A

Organic Letters

Volumn 1, Issue 1, 1999, Pages 169-171

  Hoye, Thomas R ^a   Zhao, Hongyu ^a  

^a University of Minnesota   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ANTIINFECTIVE AGENT; ANTINEOPLASTIC ANTIBIOTIC; CALLIPELTOSIDE A; MACROLIDE; PEPTIDE FRAGMENT;

ANIMAL; ARTICLE; CHEMISTRY; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; SPONGE (PORIFERA); SYNTHESIS;

ANIMALS; ANTI-BACTERIAL AGENTS; ANTIBIOTICS, ANTINEOPLASTIC; MACROLIDES; MAGNETIC RESONANCE SPECTROSCOPY; PEPTIDE FRAGMENTS; PORIFERA;

EID: 0033564998     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol9906514     Document Type: Article

References (29)

1. Zampella, A.; D'Auria, V.; Minale, L.; Debitus, C.; Roussakis, C. J. Am. Chem. Soc. 1996, 118, 11085-8.
2. Evans, D. A.; Fitch, D. M. J. Org. Chem. 1997, 62, 454-5.
3. 2AlN(Me)OMe, the main product was i. An analogous byproduct was recently described (Romo, D.; Rzasa, R. M.; Shea, H. A.; Park, K.; Langenhan, J. M.; Sun, L.; Akheizer, A.; Liu, J. O. J. Am. Chem. Soc. 1998, 120, 12237-54). (equation presented)
4. 2AlN(Me)OMe, the main product was i. An analogous byproduct was recently described (Romo, D.; Rzasa, R. M.; Shea, H. A.; Park, K.; Langenhan, J. M.; Sun, L.; Akheizer, A.; Liu, J. O. J. Am. Chem. Soc. 1998, 120, 12237-54). (equation presented)
5. 13C NMR, IR, and MS data.
6. Linderman, R. J.; Cutshall, N. S.; Becicka, B. T. Tetrahedron Lett. 1994, 35, 6639-42.
7. 2=CHLi to 6 gave a complex mixture of products, which included the aldehyde ii as the major product (∼20%). This reduction might proceed by way of complex iii between a molecule of 6 and the magnesium salt of allyl alcohol. Fragmentation of a Weinreb amide to formaldehyde has been recently reported (Seong, M. R.; Kim, J. N.; Kim, H. R.; Ryu, E. K. Synth. Commun. 1998, 28, 139-45). (equation presented)
8. 2=CHLi to 6 gave a complex mixture of products, which included the aldehyde ii as the major product (∼20%). This reduction might proceed by way of complex iii between a molecule of 6 and the magnesium salt of allyl alcohol. Fragmentation of a Weinreb amide to formaldehyde has been recently reported (Seong, M. R.; Kim, J. N.; Kim, H. R.; Ryu, E. K. Synth. Commun. 1998, 28, 139-45). (equation presented)
9. Evans, D. A.; Chapman, K. T.; Carreira, E. M. J. Am. Chem. Soc. 1988, 110, 3560-78.
10. 13C NMR analysis clearly indicated the 1,3-anti vs 1,3-syn nature of each: Rychnovsky, S. D.; Skalitzky, D. J. Tetrahedron Lett. 1990, 31, 945-8. Evans, D. A.; Rieger, D. L.; Gage, J. R. Tetrahedron Lett. 1990, 31, 7099-100. Rychnovsky, S. D.; Rogers, B.; Yang, G. J. Org. Chem. 1993, 58, 3511-15.
11. 13C NMR analysis clearly indicated the 1,3-anti vs 1,3-syn nature of each: Rychnovsky, S. D.; Skalitzky, D. J. Tetrahedron Lett. 1990, 31, 945-8. Evans, D. A.; Rieger, D. L.; Gage, J. R. Tetrahedron Lett. 1990, 31, 7099-100. Rychnovsky, S. D.; Rogers, B.; Yang, G. J. Org. Chem. 1993, 58, 3511-15.
12. 13C NMR analysis clearly indicated the 1,3-anti vs 1,3-syn nature of each: Rychnovsky, S. D.; Skalitzky, D. J. Tetrahedron Lett. 1990, 31, 945-8. Evans, D. A.; Rieger, D. L.; Gage, J. R. Tetrahedron Lett. 1990, 31, 7099-100. Rychnovsky, S. D.; Rogers, B.; Yang, G. J. Org. Chem. 1993, 58, 3511-15.
13. (b) Mosher ester analysis (Dale, J. A.; Mosher, H. A. J. Am. Chem. Soc. 1973, 95, 512-9) clearly supports the assignment of C(9)-R vs C(9)-S configuration in the major and minor diastereomers of 8.
14. (a) Oikawa, Y.; Yoshioka, T.; Yonemitsu, O. Tetrahedron Lett. 1982, 23, 889-92.
15. (b) Wang, Z. Tetrahedron Lett. 1989, 30, 6611-4.
16. 2) we isolated only the Friedel-Crafts product iv (in 50% yield) from the mixture of products. Under basic conditions (NaH, PMB-Cl, THF, 0°C) retroaldol fragmentation predominated. (equation presented)
17. Clemens, R. J.; Hyatt, J. A. J. Org. Chem. 1985, 50, 2431-5.
18. This cyclization was performed using 1 mg of pure 13-maj. A second diastereomer of 14, which we presume to be its anomeric epimer, was also observed (∼1:10 ratio).
19. The reported value for the vicinal (H-H) coupling constant in a relevant 1,3-syn-acetal is much larger (J = 9.2 Hz; Evans, D. A.; Gauchet-Prunet, J. A. J. Org. Chem. 1993, 58, 2446-53) than that reported for a relevant 1,3-anti-acetal (J = 5.4 Hz; Roush, W. R.; Bannister, T. D.; Ermolendo, M. S.; Yashunsky, D. V.; Borodkin, V. S. Tetrahedron Lett. 1992, 33, 3587-90).
20. The reported value for the vicinal (H-H) coupling constant in a relevant 1,3-syn-acetal is much larger (J = 9.2 Hz; Evans, D. A.; Gauchet-Prunet, J. A. J. Org. Chem. 1993, 58, 2446-53) than that reported for a relevant 1,3-anti-acetal (J = 5.4 Hz; Roush, W. R.; Bannister, T. D.; Ermolendo, M. S.; Yashunsky, D. V.; Borodkin, V. S. Tetrahedron Lett. 1992, 33, 3587-90).
21. (a) Xu, Z.; Johannes, C. W.; Houri, A. F.; La, D. S.; Cogan, D. A.; Hofilena, G. E.; Hoveyda, A. H. J. Am. Chem. Soc. 1997, 119, 10302-16 and earlier rets therein.
22. (b) For a recent review that includes known examples of macrocyclization reactions, see: Grubbs, R. H.; Chang, S. Tetrahedron 1998, 54, 4413-50.
23. 6 by NMR spectroscopy, which implies initial loading of the metal onto one of the olefins in 13. However, the reaction is very slow and the overall conversion is low. We were unable to determine the fate of the resulting Mo-alkylidene.
24. Linalool rapidly underwent RCM with 15 under conditions where linalool methyl ether was unreactive. We are continuing to study this phenomenon and report additional details elsewhere.
25. Prepared from 8 by the sequence: (i) DDQ; (ii) TESOTf; (iii) DIBALH; (iv) Swern; (v) addition of dianion of 3; and (vi) HF/MeOH.
26. A major advantage of in situ NMR monitoring is that we can quickly assess with confidence whether a given substrate will engage in initial reaction with a given metal-carbene initiator (by the presence or absence of styrene and/or new M=CHR resonances). This in turn has permitted us to prepare only ∼ 1 mg of numerous complex substrates and confidently judge their reactivity.
27. 3 at room temperature. Ketone 17 was the major product observed by direct NMR and GC/MS analysis of the reaction mixture and the only product (along with an approximately equal amount of starting 8) isolated following HPLC purification.
28. 18 to a methyl ketone, perhaps in the form of its hemiketal to the C(5)-OH.
29. For example, see: Kirkland, T. A.; Grubbs, R. H. J. Org. Chem. 1997, 62, 7310-7318.