US8513226: Simultaneous method for the preparation of a mixture of 3-acetoxy-17-acetamido-16-formyl-androst-5,17-diene and 3-acetoxy-2'-chloro-5-androsteno[17,16-b]pyridine

The invention relates to the preparation and biological evaluation of 3-acetoxy-17-acetamido-16-formyl-androst-5,17-diene (4) and 3-acetoxy2'-chloro-5-androsteno[17,16-b]pyridine (5) as gastric proton pump inhibitor and their comparison to that of omeprazole, a clinically employed anti-gastric ulcer drug. Compound (4) exhibited dose-dependent inhibition of histamine-stimulated acid secretion in gastric parietal cell with an IC50 value comparable to cimetidine. No mortality or behavioral abnormality of Swiss albino mice was observed under single-dose level of 1 g/Kg body weight of compound (4). Compound (4) further exhibited excellent anti-ulcer activity in vivo against indomethacin-induced ulcer.