A two step facile synthesis of new steroidal linear and angular pyranones having anti-mycobacterial activity

Title compounds 2',2'-dimethylcholesta-2,4-dien3,2-b]-pyran-4'-one(3),2',2'-dimethyl-3β-substituted cholesta-4,6-dien7,6-b]-pyran-4'-one(6a,b)and(6c)were prepared by the cyclization of 2-acetylcholesta-2,4-dien-3-ol(2),6-acetyl-3β-substituted-cholesta-4,6-dien-7-ol(Sa,b)and(5c)respectively,with pyrrolidine,dry benzene and dry acetone using Dean Stark separator through conventional heating.Furthermore,compounds were also found to be active against Mycobacterium tuberculosis.