Abstract: Compounds of the formula ##STR1## wherein R is a hydrogen atom or an acyl; U is --O--, --CHR.sup.1 -- or --NR.sup.2 -- wherein R.sup.1 is a hydrogen atom or a hetero ring, and R.sup.2 is a hydrogen atom or a lower alkoxycarbonyl lower alkyl; V is --O--, --S--, --CHR.sup.3 -- or --NR.sup.4 -- wherein R.sup.3 is a hydrogen atom or a lower alkoxycarbonyl, and R.sup.4 is a hydrogen atom, a lower alkyl or an acyl; W is methyl, a hetero ring or optionally substituted phenyl; X and Y are the same or different and each is --CH.sub.2 -- or --S--; m is an integer of 0 to 6; and n is an integer of 1 to 4, and pharmaceutically acceptable salts thereof.The compounds of the present invention have specifically strong inhibitory activity against prolyl endopeptidase, and suppress decomposition and inactivation of TRH, substance P, neurotensin, vasopressin and the like. Accordingly, the compounds can be used for the prophylaxis and/or treatment of dementia and amnesia including Alzheimer's disease.

Abstract: The present invention provides carbamoyl-2 -pyrrolidinone compounds useful as medicaments for improving cerebral functions and activating cerebral metabolism or protecting against anoxic brain damage.

Abstract: The present invention provides a carbamoyl-2-pyrrolidinone compound which has the following formula (2) and is useful as medicaments for treating senile dementia, i.e., as cerebral function improving agents and cerebral metabolism activators or anoxic brain damage protectives ##STR1## wherein R.sup.1 is a hydrogen atom, hydroxyl or lower alkyl substituted or unsubstituted with hydroxyl, and R.sup.3 is phenyl, tetrahydronaphthyl, pyridyl or thiazolyl having or not having lower alkoxyl, lower alkylamino, a halogen atom or halogenomethyl as a substituent.Further, the present invention provides novel carbamoyl-2-pyrrolidinone compounds represented by the formula ##STR2## wherein R.sup.1 is a hydrogen atom, hydroxyl or lower alkyl substituted or unsubstituted with hydroxyl, and R.sup.2 is phenyl, tetrahydronaphthyl, pyridyl or thiazolyl having or not having methoxy or lower alkylamino as a substituent, provided that when R.sup.1 is a hydrogen atom or unsubstituted lower alkyl, R.sup.2 is not unsubstituted phenyl.