| 摘要 |
Compound of formula (I): wherein: R1 and R2 each represents a group selected from hydrogen, alkyl, arylalkyl, hydroxy, hydroxyalkyl, dihydroxyalkyl, alkoxy, alkoxyalkyl, amino and aminoalkyl (optionally substituted), Ra and Rb each represents an alkylene chain, X1, X2 and X3 each represents a group selected from hydroxy, alkoxy, aryloxy, arylalkoxy, alkyl, amino (optionally substituted), halogen, alkylcarbonyloxy and azido, X4 represents a methylidene group or a group of formula -Rc-X1 as defined in the description, their isomers and also their addition salts with a pharmaceutically acceptable acid or base. |
