Synthesis and post-coital contraceptive activity of ether and ester analogues of 2,3-diaryl-2H-1-benzopyrans

Ether and ester analogues of 2,3-diaryl-2H-1-benzopyrans have been synthesised and tested for their pregnancy inhibiting activity in immature rats. Some of the compounds exhibit potent activity. Structure-activity relationship relative to the hydroxy analogue has been discussed. In general, esters were found to be better inhibitory agents.