| abstract |
(57) [Summary] [Objective] To provide a novel PG derivative having a potent renal disease-improving action, ischemic heart disease-improving action, heart failure-improving action or intraocular pressure-lowering action. ## STR1 ## Formula (I): [In the formula, R 1 represents an alkyl group having 1 to 6 carbon atoms, R 2 represents a cycloalkyl-substituted methyl group having 5 to 7 carbon atoms, or a bridged cyclic hydrocarbon. ] The prostaglandin derivative or its salt represented by these, and the renal disease improving agent which contains this derivative or its salt as an active ingredient, or an ischemic heart disease improving agent or a heart failure improving agent. |