ACYLATION OF THE 4,5- AND 5,6-DOUBLE BOND ISOMERS OF 3-STEROIDAL THIAZOLIDINES. THE CHEMICAL STABILITY OF SPIRO 3-STEROIDAL 4,5- AND 5,6-DOUBLE BOND ISOMERS

Article abstract of DOI:10.1016/S0040-4020(01)98860-X

It has been shown that the 5,6-double bond steroidal thiazolidines can be N-acylated if there is no substituent in the 4'-position on the thiazolidine ring; substituents in the 4'-position of the thiazolidine sterically hinder acylation.On the other hand, the 4,5-double bond steroidal thiazolidine isomers decomposed on attempted acylation.The lability of these 4,5-double bond isomers was attributed to the contribution oh hyperconjugative resonance form to the structure of the 4,5-double bond isomers.