The Synthesis of the Common C31-C40 Fragment of Pectenotoxins

Synlett

Volumn 1997, Issue 11, 1997, Pages 1300-1302

  Amano, Seiji ^a   Fujiwara, Kenshu ^a   Murai, Akio ^a  

^a HOKKAIDO UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0002064223     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-1997-1033     Document Type: Article

References (20)

1. (a) Yasumoto, T.; Murata, M.; Oshima, Y.; Sano, M.; Matsumoto, G. K.; Clardy, J. Tetrahedron 1985, 41, 1019.
2. (b) Murata, M.; Sano, M.; Iwashita, T.; Naoki, H.; Yasumoto. T. Agric. Biol. Chem. 50, 2693 (1986).
3. (c) Yasumoto, T.; Murata, M.; Lee, J.-S.; Torigoe, K. Mycotoxins and Phycotoxins '88, 375 (1989).
4. T. Yasumoto, Private Commun., May 6th, 1997. When we started these synthetic studies, the structures of PTXs have been proposed as the enantiomers of the fixed absolute configurations by Prof. Yasumoto.
5. Kozikowski, A. P.; Stein, P. D. J. Org. Chem. 1984, 49, 2301.
6. Roush, W. R.; Adam, M. A.; Peseckis, S. M. Tetrahedron Lett. 1983, 24, 1377.
7. Cf., Caron, M.; Sharpless, K. B. J. Org. Chem. 1985, 50, 1557.
8. 1H-NMR spectrum shows that the protons adjacent to the mesyloxy group in 10 and the acetoxy group in 11 correspond to C2 in 10 and 11 [C2 in 10: δ4.94 (1H, ddd, J=3.0, 5.7, 7.3 Hz), C2 in 11: δ5.14 (1H, dt, J=4.3, 5.6 Hz)]. Thus, the scrambling reaction did not occur.
9. Oikawa, Y.; Tanaka, T.; Horita, K.; Yonemitsu, O. Tetrahedron Lett. 1984, 25, 5397.
10. Corey, E. J.; Palani, A. Tetrahedron Lett. 1995, 36, 3485.
11. Cf., Rychnovsky, S. D.; Powers, J. P.; LePage, T. J. J. Am. Chem. Soc. 1992, 114, 8375.
12. Freeman, P. K.; Hutchinson, L. L. J. Org. Chem. 1980, 45, 1924.
13. Selected NOEs are shown.
14. Still, W. C.; Sreekumar, C. J. Am. Chem. Soc. 1980, 102, 1201.
15. When 5 (1 eq) and 3 (2 eq) were used, the corresponding selectivity was unchanged, though the yield was dropped down to 34%. It was suggested that there might be no difference between the reaction rates of 4 and 14.
16. For the stereoselective generation of α-lithiated reagents from α-phenylthio-tetrahydropyrans by reductive lithiation, see; (a) Cohen, T.; Lin, M. T. J. Am. Chem. Soc. 1984, 106, 1130.
17. (b) Rychnovsky, S. D., Mickus, D. E. Tetrahedron Lett. 1989, 30, 3011.
18. The detailed mechanistic studies on the stereoselective generation of the α,α'-trans-alkylated tetrahydrofurans are in progress aiming to the general development of the procedure in our laboratory.
19. The structures of these isomers were deduced to be the corresponding 2,5-cis-compound as well as the 2,5-trans-compound isomeric at C7. The epimerization in the latter seems to occur during the Swern oxidation.
20. 8Si 580.3432, found 580.3429.