9,10-Disubstituted acridines

Telomerase is an attractive target for the design of new anticancer drugs. Harrison et al. [24] synthesized a series of 3,6-disubstituted acridines (II) on the basis that inhibition of telomerase occurs by stabilizing G-quadruplex... 

Varying amounts of acridone are produced along with carbazoles when salicyl 2-azidobenzoates (36) are pyrolysed at 400°C. The acridone predominates with the phenyl ester (M.G. Clancy, M.M. Hesabi and 0. Meth-Cohn, Cbm. Comm., 1980, 1112) and later work indicates that the amount of acridone increases as the leaving group efficiency of OR increases (.idem, J. chem. Soc. Perkin I, 1984, 429). Spray pyrolysis of 2,6-disubstituted phenyl 2-azidobenzoates leads to a mixture of 4-substituted 9,10-dihydroacridine and the corresponding acridine, possibly involving ipso attack by the nitrene. 

Several classes of ligands have been described such as porphyrins, perylenes, amidoanthracene-9,10-diones, 2,7-disubstituted amidofluoren-ones, acridines, ethidium derivatives,disubstituted triazines, fluoroquinoanthroxazines, indoloquinolines, dibenzophenanthrolines, ... 

Reactions of dibenzopyridines show analogies with pyridine, quinoline and isoquinoline. Acridine and phenanthridine are A-protonated by strong protic acids, iV-alkylated by alkyl halides and A-oxidized by peroxy acids. Electrophilic substitutions of acridine often result in disubstitution at the 2- and 7-positions (e.g. nitration giving 3), whereas those of phenanthridine occur at different positions (e.g. nitration mainly at the 1- and 10-position yielding 4 and 5) ... 

Quinolines and isoquinolines have three bands near 1600cm (6.25pm) and five in the range 1500-1300cm (6.67-7.69pm). Disubstituted methyl quinolines have four bands in the region 1600-1500 cm (6.25-6.67 pm). The aromatic C-H out-of-plane deformation vibrations are similar to those observed for naphthalenes. (Reviews of the infrared speetra of acridines have been published. )... 

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