| abstract |
The present invention is directed to a compound of formula (I), wherein R represents a hydrogen atom or an acyl, aroyl or cycloalkylcarbonyl radical or a residue of formula (Ia); R1? represents an alkyl radical; R2? represents an aryl or heteroaryl radical, or R1? represents an alkylene chain attached to a carbon atom in an ortho position of the R2? aryl or heteroaryl radical relative to a carbon of the R2? aryl or heteroaryl radical linked to the propanoyl moiety; R3? represents a hydrogen atom or an alkyl, aryl, alkoxy or aryloxy radical; and R' represents a hydrogen atom or an alkyl, aralkyl, acyl or aroyl radical; and the pharmaceutically acceptable salts thereof. The invention is also directed to the preparation of these compounds, pharmaceutical compositions comprising the compounds and methods for their pharmaceutical use. |