Abstract: Compounds of general formula (I) in which U represents a group of general formula (A) or (B) in which formulae V represents a hydrogen or halogen atom, a (C1-C3)alkyl group or one or two (C1-C3)alkoxy groups, W and X each represent, respectively, either two oxygen atoms, or an oxygen atom and a CH2 group, or a CH2 group and an oxygen atom, or an oxygen atom and a CO group, n represents the number 0 or 1, R represents either a propyl group when U represents a group of general formula (A), or a hydrogen atom or a (C1-C3)alkyl group when U represents a group of general formula (B), Y represents one or more atoms or groups chosen from the following: hydrogen, halogen, (C1-C3)alkyl and (C1-C3)alkoxy, Z represents two hydrogen atoms or an oxygen atom.

Abstract: Compound corresponding to the formula: ##STR1## in which X represents one or more of hydrogen, halogen, alkyl, trifluoromethyl, alkoxy, alkylthio, methylsulphonyl, cyano, ethoxycarbonyl, aminocarbonyl and carboxy, Y represents one or more of hydrogen, halogens, alkyl, trifluoromethyl, methoxy and trifluoromethoxy, R.sub.1 represents hydrogen, alkyl, phenylmethyl, 2-phenylethyl, acetyl or alkoxycarbonyl, R.sub.2 and R.sub.3 each represent hydrogen, alkyl which is optionally substituted, prop-2-enyl, prop-2-ynyl, phenyl, 1-(phenylmethyl)piperidin-4-yl, or 1-[(cyclohexen-1-yl)methyl]piperidin-4-yl, or alternatively R.sub.2 and R.sub.3 form, with the nitrogen atom carrying them, an optionally substituted heterocycle. These compounds are useful as hypnotic, anxiolytic and anticonvulsant agents.