EP0080822A1 — Anti-hypertensive prolinol-based peptides

USPTO Abstract

Compounds of formula (I): or a pharmaceutically acceptable salt thereof, wherein R 1 is C 1-5 alkyl optionally substituted by NHR 6 , (wherein R 6 is hydrogen or C 1-5 alkylcarbonyl) or by phenyl or naphthyl optionally substituted by halogen, C 1-5 alkyl or C 1-5 alkoxy or by dihydrobenzofuran-2-yl, optionally substituted in the benzo moiety by C 1-5 alkyl, C 1-5 alkoxy, hydrogen or trifluoromethyl; R 2 and R 5 are the same or different and each is hydroxy, C 1-5 alkoxy, C 2-6 alkylcarbonyl or amino optionally substituted by C 1-5 alkyl; R 3 is C 1-5 alkyl optionally substituted by the group -NHR 7 , wherein R 7 is hydrogen, C 1-5 alkyl or C 2-6 alkylcar- bonvl; and R 4 is phenyl optionally substituted by halogen, C 1-5 alkoxy, trifluoromethyl or C 1-5 alkyl having antihypertensive activity, a process for their preparation and their use.