RENIN INHIBITORS: 5 AMINO-4-HYDROXYVALERYL SULPHUR SUBSTITUTED DERIVATIVES

Compounds of the formula (I) in which R1 represents acyl substituted by a thio, sulphinyl or sulphonyl group, A represents an optionally N-alkylated alpha -amino acid residue that is bonded N-terminally to R1 and C-terminally to the group -NR2-, R2 represents hydrogen or lower alkyl, R3 represents hydrogen, lower alkyl, optionally etherified or esterified hydroxy-lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, bicycloalkyl-lower alkyl, tricycloalkyl-lower alkyl, aryl or aryl-lower alkyl, R4 represents hydroxy or etherified or esterified hydroxy, R5 represents lower alkyl, optionally etherified or esterified hydroxy-lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, bicycloalkyl, bicycloalkyl-lower alkyl, tricycloalkyl, tricycloalkyl-lower alkyl, aryl, aryl-lower alkyl, optionally substituted carbamoyl, optionally substituted amino, optionally substituted hydroxy, optionally substituted mercapto, sulyhinyl or sulphonyl, and R6 represents substituted amino, and salts of such compounds having salt-forming groups, inhibit the blood pressure-increasing action of the enzyme renin and can be used as anti-hypertensives.