Synthetic strategies to a telomere-targeted pentacyclic heteroaromatic salt†
Abstract
Three routes have been explored to synthesise the telomere-targeted agent 3,11-difluoro-6,8,13-trimethyl-8H-quino[4,3,2-kl]acridinium methosulfate 3. Application of a 6-(2-azidophenyl)phenanthridine precursor 11 gave an entry to the indazolo[2,3-f]phenanthridine ring system 12 not the required quino[4,3,2-kl]acridine. A six step synthesis starting from