Download full text in PDF Opens in a new window. Article suggestions will be shown in a dialog on return to ScienceDirect. ... Please enable JavaScript to use all the features on this page. ... Synthesis and structure-activity relationships (SAR) of orally active arginine vasopressin (AVP) receptor antagonists are discussed. Potent and orally active AVP receptor antagonists are produced when ring A or VPA-985 (1) is replaced with a 3-pyridinyl unit (2).