… and its 20'-epimer through racemic and enantioselectively generated intermediates. New syntheses of D/E-cis-and trans-. PSI.-vincadifformines and D/E-cis-and-trans …
ME Kuehne, WG Bornmann
文献索引:Kuehne, Martin E.; Bornmann, William G. Journal of Organic Chemistry, 1989 , vol. 54, # 14 p. 3407 - 3420
Vindoline (20), on reaction with chloro imine derivatives of the D-seco-D/E-trans-\ k-and-20- epi-@-vincadifformines 18 and 19, followed by cyclization and debenzylation steps, provided the natural products 20'-deoxyvinblastine (4) and 20'-deoxyleurosidine (5) and their diastereomers 6 and 7, in two atropisomeric forms. These reactions gave exclusively the pharmacologically critical C16'-C14'parf stereochemistry. Intermediates 18 and 19 ...