A model study of epothilone synthesis: an alternative synthetic approach to the C1-C7 fragment

Abstract

In this model study an alternative synthetic approach to the C1-C7 fragment of epothilones was investigated. Starting froth 4,4-dimethylcyclopentenone, a 7 step reaction sequence afforded the key intermediate 7 in 27%, overall yield. Surprisingly, the attempted deprotection of latent functionalities in 7 failed, indicating the incompatibility of the ethoxyethyl protective group with the reaction conditions employed.

U okviru model studije ispitivan je alternativni sintetički pristup C1–C7 fragmentu molekula epotilona. Polazeći od 4,4-dimetilciklopentenona, ključni intermedijer 7 dobijen je u sedam faza, u ukupnom prinosu od 27 %. Deprotekciju latentnih funkcionalnih grupa u molekulu 7 nije bilo moguće izvršiti, zbog iznenađujuće labilnosti etoksietil zaštitne grupe u baznim reakcionim uslovima.