Synthesis of novel amides and esters prodrugs of olmesartan is described. Their in vitro stability in rat plasma was tested. The results showed that the ester derivative IIa with n-octyl substituted dioxolone moiety was rapidly converted into olmesartan within 30min. The pharmacokinetic parameters of IIa were studied and compared with those of olmesartan medoxomil. Compound IIa is proposed to be a promising prodrug of olmesartan.
