Acridines, 9-substitution

Tatibouet, A. Demeunynck. M. Andraud, C. Collet. A. Lhomnie, J. Synthesis and study of an acridine substituted Troger s base Preferential binding of the (—)-isomerto B-DNA. J. Chem. Soc. Commun. 1999. 161-162. 

In Volume 2, in the chapter on Free-Radical Substitutions of Heteroaromatic Compounds by R. O. C. Norman and G. K. Radda, p. 166, Table VI, 6-R-Acridine should read 9-R-Acridine p. 167, lines 17 and 18, 6-phenylacridine should read 9-phenyl-acridine... 

The pioneering work carried out in Germany in the 1920s showed that appropriately substituted aminoquinolines and amino-acridines afforded a series of synthetic compounds that exhibited antimalarial activity.The exigencies of the Second World War led to a massive program aimed at the same goal in this country. This work led to the development of two distinct structural classes of quinoline antimalarials the 4-amino-7-chloroquino-... 

An acridine with a radically different substitution pattern, interestingly, still exhibits antimalarial activity. Condensation of acetone with diphenylamine in the presence of strong acid affords the partly reduced acridine, 20. Alkylation with 3-chloro-dimethylaminopropane (via the sodium salt of 20) affords dimethacrine (21). ... 

When the name ends in -insdure the translator may substitute -ic acid for this unless another acid already bears the resulting name thus Akridinsdure is often called acridic acid instead of the longer acridinic acid, but Mekonin-sdure should be translated meconinic acid because Mekonsdure has preempted the translation meconic acid. Such exceptions are given in the dictionary as far as possible, but in doubtful cases the longer form -inic acid would be the safer. 

Harrison RJ et al. (1999) Human telomerase inhibition by substituted acridine derivatives. Bioorg Med Chem Lett 9(17) 2463-2468... 

The aromatic spacer group of the model receptors prevent the formation of intramolecular hydrogen bonds between the opposing carboxyls yet these functions are ideally positioned for intermolecular hydrogen bonds of the sort indicated in 32. The acridine derivatives do indeed form stoichiometric complexes with oxalic, malonic (and C-substituted malonic acids) as well as maleic and phthalic acids, Fumaric, succinic or glutaric acids did not form such complexes. Though protonation appears to be a necessary element in the recognition of these diacids, the receptor has more to... 

Di GC, De MM, Chiron J, Delmas F (2005) Synthesis and antileishmanial activities of 4, 5-di-substituted acridines as compared to their 4-mono-substituted homologues. Bioorg Med Chem 13 5560-5568... 

Because of the close relations between lucigenin, N-alkylacridones, and other 9-substituted acridines, it appears appropriate to consider the chemiluminescence reactions of all these compounds simultaneously. 

Under basic conditions, A -acridinylmethyl-substituted thiourea 449 placed in the presence of bromoacetonitrile gave rise to the unexpected formation of the spiro[dihydro-acridine-9(10//),2 -(2, 7 -dihydro-3 //-imidazo[l,2-c]thiazol-5 -ylidene-/>-nitrophenyl)amine] 450 in 67% yield. The reaction involved displacement of the bromine atom of... 

There are many interesting derivatives of quinoline and acridine obtained by substitution. In particular, 8-hydroxyquinoline (oxine) is the second complexing agent in importance after EDTA. Sulfonation in position 5 leads to a compound which is soluble in water and that exhibits outstanding fluorogenic properties (i.e. fluorescence enhancement) on complexation with metal ions (e.g. aluminum). 

Products isolated from the thermal fragmentation of A-arylbenzamide oximes and A-arylbenzamide O-phenylsulfonyl oximes have been accounted for by invoking a free-radical mechanism which is initiated by the preferential homolysis of the N-O bond." Time-resolved IR spectroscopy has revealed that photolysis of A, A -diphenyl-l,5-dihydroxy-9,10-anthraquinone diimine affords acridine-condensed aromatic products via excited-state intramolecular proton transfer." The absolute and relative rates of thermal rearrangements of substituted benzyl isocyanides have been measured,and it has been found that the relative rates are independent of temperature and exhibit excellent Hammett correlations. Thionitrosoarene (25), thought to be generated by desulfurization of the stable A-thiosulfinylaniline (24), has been established" " as an intermediate in the formation of 3,3a-dihydro-2,l-benzisothiazole (26) from o-alkylthionitrosoarene (24). 

Substitution of the nine position is a common transformation for acridines. An optimized method for preparing the 9-carboxamides uses BOP/DMF <99SC4341>. Reaction of 9-isothioacridines with the sodium anion of diethylmalonate is followed by alkylation with bromoacetate to afford the spiro[dihydroacridine-9(10i/)-thiazolidines] <99H(51)137>. 

Azonia substitution at a naphthalene bridgehead position gives the quinolizinium ion (16). Oxonia substitution, elsewhere, forms the 1- and 2-benzopyrylium ions (17) and (18). The two most well-known monoaza systems with three aromatic fused rings are acridine (19), derived structurally from anthracene, and phenanthridine (20), an azaphenanthrene. The better-known diaza systems include phenazine (21) and 1,10-phenanthroline (22), while systems with three linearly fused pyridine rings are called anthyridines, e.g. the 1,9,10-isomer (23). 

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