THIO-SUBSTITUTED BENZOYLPROPIONYL-L-PROLINES

The present invention provides novel substituted omega -aroyl(propionyl or butyryl) -L-prolines, pharmaceutical compositions containing them useful for reducing blood pressure by inhibiting the conversion of angiotensin I to angiotensin II, and processes for preparing the novel compounds. The novel compounds are those of the formulae: wherein n is zero or one; R1 is hydrogen or alkyl having up to 3 carbon atoms; R2 is hydrogen, phenyl or alkyl having up to 3 carbon atoms; R3 is mercapto, formylthio, benzoylthio, all anoylthio having from 2 to 4 carbon atoms or moieties of the formulae: -S-CO2R5 , -S-CH2CO2R5 -S-@-NHR5 , and and wherein R9 is phenyl or substituted phenyl; R4 is hydrogen, phenyl or alkyl having up to 4 carbon atoms; R5 is hydrogen or alkyl having up to 4 carbon atoms; and ARYL is selected from the group consisting of 1-naphthyl, 2-naphthyl, 4-chloro-1-naphthyl 5,6,7,8-tetrahydro -1-naphthyl, 5, 6, 7, 8-tetrahydro -2-naphthyl, 4-methoxy-1 -naphthyl, 5-acenaphthyl, 4-biphenylyl, 5-indanyl, 4-indanyl and moieties of the formula: wherein R6 is selected from the group consisting of hydrogen, fluoro, chloro, bromo, trifluoromethyl, cyano, amino, phenoxy, halophenoxy, phenylthio, halophenylthio, p-cyclohexylphenoxy, alkyl having up to 4 carbon atoms, alkoxy having up to 4 carbon atoms, alkylamino having up to 4 carbon atoms, alkanoylamino having from 2 to 4 carbon atoms and alkoxycarbonyl having from 2 to 4 carbon atoms, R7 is selected from the group consisting of chloro, fluoro, bromo, alkyl having up to 4 carbon atoms and alkoxy having up to 4 carbon atoms, and m is zero, one or two; and the pharmacologically acceptable cationic salts thereof when R5 is hydrogen.