Enantioselective total synthesis of the marine alkaloid clavepictines A and B

Journal of Organic Chemistry

Volumn 61, Issue 15, 1996, Pages 4882-4883

  Toyooka, Naoki ^a   Yotsui, Yasuhito ^a   Yoshida, Yasuko ^a   Momose, Takefumi ^a  

^a UNIVERSITY OF TOYAMA   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

ALKALOID; CLAVEPICTINE A; CLAVEPICTINE B; CYTOTOXIC AGENT; UNCLASSIFIED DRUG;

ARTICLE; CHIRALITY; DRUG PURITY; DRUG SYNTHESIS; ENANTIOMER; REACTION ANALYSIS;

EID: 0030056407     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo9608174     Document Type: Article

References (12)

1. Raub, M. F.; Cardellina, J. H., II; Choudhary, M. I.; Ni, C.-Z.; Clardy, J.; Alley, M. C. J. Am. Chem. Soc. 1991, 113, 3178-3180.
2. Kong, F.; Faulkner, D. J. Tetrahedron Lett. 1991, 32, 3667-3668.
3. Hart, D. J.; Leroy, V. Tetrahedron 1995, 51, 5757-5770.
4. The intramolecular conjugate addition reaction with nitrogen nucleophiles has been recognized as a powerful tool for construction of piperidine ring systems; see: Akiyama, E.; Hirama, M. Synlett 1996, 100-102 and references cited therein.
5. Toyooka, N.; Yoshida, Y.; Momose, T. Tetrahedron Lett. 1995, 36, 3715-3718. An alternative stereoselective chiral synthesis of the dibenzyl ether of (-)-4 from D-serine was reported; see: Campbell, J. A.; Lee, W. K.; Rapoport, H. J. Org. Chem. 1995, 60, 4602-4616.
6. Toyooka, N.; Yoshida, Y.; Momose, T. Tetrahedron Lett. 1995, 36, 3715-3718. An alternative stereoselective chiral synthesis of the dibenzyl ether of (-)-4 from D-serine was reported; see: Campbell, J. A.; Lee, W. K.; Rapoport, H. J. Org. Chem. 1995, 60, 4602-4616.
7. Satisfactory analytical and spectral data were obtained for all new compounds. Optical rotations were taken in chloroform unless otherwise stated.
8. (1,2) strain, and a stereoelectronic effect has been reported for the reduction of an iminium salt of this type of piperidine; see: Cook, G. R.; Beholz, L. G.; Stille, J. R. J. Org. Chem. 1994, 59, 3575-3584.
9. Dong, Q.; Anderson, C. E.; Ciufolini, M. A. Tetrahedron Lett. 1995, 36, 5681-5682.
10. Fixation of the ring conformation (i.e., presence of the acetonide protecting group) was indispensable for exclusive formation of 10. For example, cyclization of 17 resulted in the formation of a ca. 4:1 mixture of trans- and cis-quinolizidines (eq 2). (Matrix Presented)
11. 3H, undesired trans-quinolizidine 19 was formed exclusively in quantitative yield. Comparison of the coupling pattern (triplet of triplets) and coupling constant (11.0, 3.0 Hz) of the bridgehead proton of 19 to (-)-10 revealed the trans ring juncture of 19 (eq 3). (Matrix Presented)
12. w = 6.4%. The authors have deposited the atomic coordinates for (-)-10 with the Cambridge Crystallographic Data Centre. The coordinates can be obtained, on request, from the Director, Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK.