title: Desaminopenicillamine tocinoic acid derivatives--inhibitors of oxytocin.
abstract: Tocinoic acid analogs with penicillamine in place of one or both of the cysteine residues have been studied and [1-beta-mercaptopropionic acid, 6-penicillamine] tocinoic acid (dPen6TA) and [1-beta,beta-dimethyl-beta-mercaptopropionic acid, 6-penicillamine] tocinoic acid (dPen1Pen6TA) have been synthesized in solution. Biological activities of these 2 compounds and those of the previously synthesized [1-beta,beta-dimethyl-beta-mercaptopropionic acid] tocinoic acid (dPen1TA) have been assayed. It was found that dPen1TA and dPen1Pen6TA, both of which have a beta,beta-dimethyl-beta-mercaptopropionic acid in position 1, are strong inhibitors of the uterine activity of oxytocin in vitro (without Mg2+) with pA2 values of 7.1 and 7.8, respectively, whereas dPen6TA with penicillamine in position 6 is a mild agonist.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D005260:Female; D007202:Indicators and Reagents; D010121:Oxytocin / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D014590:Uterine Contraction / Q000187:drug effects
chemical_list: D007202:Indicators and Reagents; C100032:tocinoic acid; D010121:Oxytocin