| abstract |
The compounds described, which are represented by the general formula (I), where X represents an oxygen atom or a group -S (O) n-, where n is equal to zero, to 1 or to 2; R represents pyridyl, substituted or unsubstituted phenyl or C1-C6 alkyl; R2, R3 and R4 are defined in the description; and Q represents hydrogen, carboxy, C2-C7 alkoxycarbonyl or a group -CON (Ra) 'Rb where Ra and Rb are defined in the description; and their pharmaceutically acceptable salts have immunomodulatory activity and are useful in particular as immunostimulatory agents in the treatment of neoplastic diseases and acute and chronic infections of both bacterial and viral origin in mammals. |