A New Approach to the Furan Degradation Problem Involving Ozonolysis of the trans-Enedione and Its Use in a Cost-Effective Synthesis of Eplerenone
摘要:
Whereas ozonization of furan 3a affords little or no carboxylic acid 5, ozonization of the corresponding trans-enedione 6 afforded carboxylic acid 5 in 82.4% yield (cryst., overall from furan, 100 g scale; after workup with dimethyl sulfide, followed by mildly basic hydrogen peroxide). This new approach to furan degradation is showcased in a cost-effective synthesis of eplerenone, an important new medicine for cardiovascular indications.
The present invention involves intermediates, including a 7α-substituted steroid (II),
and processes which are used to prepare eplerenone, a useful pharmaceutical agent.