| abstract |
The present invention relates to compounds of formula (I) <IMAGE> (I) wherein Ar is a triphenylene or substituted triphenylene ring system; R1 is a C1-3 alkylene moiety; R2 is hydrogen or a C1-6 alkyl group; R3 is a hydroxy C1-6 alkyl group; R4 and R5 are the same or different and are hydrogen, C1-6 alkyl or hydroxy C1-6 alkyl, esters thereof derived from condensation of carboxylic acids and hydroxyl groups of R3, R4, and R5; Acid addition salts thereof, which have been found useful for the treatment of tumors in mammals. |