Process for the preparation of 7 α-(methoxycarbonyl)-3-OXO-17alpha-pregn-4,9(11)-dien-21,17-carbolactone, a useful intermediate for the synthesis of molecules with pharmacological activity

摘要

An improved process for the preparation of intermediate (V) through the elimination of a molecule of water from intermediate (IV) is described.;
Intermediate (V) is a key molecule for the synthesis of eplerenone, a synthetic steroid with pharmacological activity used in the treatment of chronic pathological conditions, including hypertension.

主权项

1. A process for the production of 7α-(methoxycarbonyl)-3-oxo-17α-pregn-4-9(11)-dien-21,17-carbolactone (V) comprising elimination of a molecule of water from 11α-hydroxy-7α-(methoxycarbonyl)-3-oxo-17α-pregn-4-en-21,17-carbolactone (IV) by reaction with a two component mixture (VI) consisting of (Et)2NCF2CHFCF3 and (Et)2NFC═CFCF3, wherein quantities of the two components of said mixture (VI) are variable in ratios such that an observed area of a minority component is not less than 75% than an observed area of a majority component as determined in a gas chromatographic analysis.