Tripeptide antithrombotic agents

Claim 1

A compound of the formula wherein A is 1) a group of the formula wherein R is a phenyl group of the formula wherein a and a′ independently are hydrogen, lower alkyl, lower alkoxy, halogen, trifluoromethyl, hydroxy, hydroxymethyl, amino, or aminomethyl; or R is thienyl, furyl, naphthyl, or naphthyl mono- or disubstituted by lower alkyl, lower alkoxy, halogen, amino, mono- or di-(lower alkyl)amino, or hydroxy; or R is cyclohexadienyl, cyclohexenyl, cyclohexyl or cyclopentyl; R₁ is hydrogen, methyl or ethyl; B is lower alkyl, lower alkoxy, hydroxy, or an amino group of the formula -N(R₂)(R₃) wherein R₂ and R₃ independently are hydrogen or lower alkyl or R₂ is hydrogen and R₃ is acetyl, haloacetyl or an oxycarbonyl group of the formula R₄-O-C(O)- wherein R₄ is C₁-C₆ alkyl, C₂-C₆ alkenyl, C₃-C₇ cycloalkyl, benzyl, nitrobenzyl, diphenylmethyl, or a phenyl group as defined above; provided that when R₁ is methyl or ethyl then B is other than methyl or ethyl or A is 2) 1-aminocyclohexyl or 1-aminocyclopentyl wherein the amino group is an -N(R₂)(R₃) group as defined above; or A is 3) a bicyclic group of the formula wherein Q is a one carbon radical represented by or a two carbon radical represented by -CH₂-CH₂-, Y is a one carbon radical represented by or a two carbon radical represented by provided that one, but not both, of Q and Y is or and, provided further that,only one of Q and Y is a two carbon radical; R₅ is hydrogen or an oxycarbonyl group as defined above; and R₆ is hydrogen, halogen, hydroxy, lower alkyl or lower alkoxy; and the dotted circle within the 6-membered ring indicates that the ring is aromatic or a perhydro ring; and the pharmaceutically acceptable non-toxic salts thereof.