A new approach to the synthesis of the 17β-butenolide fragment of cardenolides
摘要:
new, efficient synthesis of the 17 beta-butenolide fragment characteristic of cardenolides is effected by [2 + 2]-cycloaddition of dichloroketene to 3 beta-acetoxypregna-5,20-diene, as a key step. (C) 1999 Elsevier Science Ltd. All rights reserved.