Abstract: Compounds of formula (I) in which R1=C1-6 alkyl, optionally halosubstituted; R2=H, C1-4 alkyl, optionally halosubstituted or replaced by halogen; R3=C2-4 alkyl, optionally halosubstituted; R4=SO2NR5R&, CO2R7 or halogen, C2-4 alkenyl; optionally substituted with NR5R6, SONR5R6, CONR5R6, CO2R7 or halogen, C2-4 alkanoyl, optionally substituted with NR5R6, SONR5R6, CONR5R6, CO2R7 or halogen; R5 and R6=independently H or C1-4 alkyl, or, together with the N atom to which they are attached, a pyrrolidino, piperidino, morpholino, 4-(NR8)-1-piperazinyl or 1-imidazolyl ring optionally substituted with one or two C1-4 alkyl groups; R7=H, C1-4 alkyl, optionally fluorosubstituted, and R8=H,C1-3 alkyl or hydroxyalkyl with 1-4 C atoms, or the pharmaceutically acceptable salts thereof are useful for the chemotherapeutic treatment of neuropathies.