Preparation of a trans-calanolide ketone intermediate and chiral separation of calanolide alcohols to give racemic calanolide A

摘要

The method of the invention comprises a process for synthesizing a trans-calanolide A ketone intermediate used in the synthesis of racemic trans-calanolide A. The invention further comprises a method for removing a racemic calanolide B diastereomer from a mixture of calanolide A and calanolide B diastereomers formed in the last step of the synthesis of calanolide A by crystallization.