Patent ID: 8217075

Claim:
A compound represented by formula (I): in which: R 1 is a hydrogen atom, an alkyl radical having 1 to 4 carbon atoms in a straight or branched chain, an alkyl radical having 2 to 4 carbon atoms in a straight or branched chain substituted by hydroxy, alkoxy, alkylthio, acyloxy, amino, alkylamino, dialkylamino, alkylcarbamoyloxy, alkoxycarbonylamino, ureido or alkylureido, R 2 is a —CO—R radical in which R is an alkyl radical, an aryl, or benzyl, a —CO—Y—R 4 radical for which Y is a heteroatom chosen from —O—, —S—, —NH—, -Nalk- for which alk is a straight or branched alkyl radical having 1 to 4 carbon atoms, and R 4 is chosen from an alkyl radical, an aryl radical, and an aralkyl radical, capable of being substituted by one or more halogen atoms or hydroxy, alkyl radicals having from 1 to 4 carbon atoms in a straight or branched chain, alkoxy, alkylthio, acylaminoalkylthio, alkoxycarbonyl or acylamino, the alkyl residues of which have 1 to 4 carbon atoms in a straight or branched chain, or oxo, or capable of being substituted by a R 5 COO— radical having R 5 that is an alkyl radical optionally substituted by benzyloxycarbonylamino, acylamino or by an amino acid residue, or an alkyl radical having 2 to 4 carbon atoms substituted by hydroxy, alkoxy, alkylthio, acyloxy, amino, alkylamino, or dialkylamino, it being understood that said substituted alkyl radical is in a straight or branched chain and has at least 2 carbon atoms between the nitrogen atom bearing R 2 and the substituent; R 3 is an alkyl radical having 1 to 4 carbon atoms in a straight or branched chain, in their R or S forms or their mixtures, as well as their pharmaceutically acceptable salts, when these exist.