Platinum acridine

Similarly to quantitative determination of high surfactant concentrations, many alternative methods have been proposed for the quantitative determination of low surfactant concentrations. Tsuji et al. [270] developed a potentio-metric method for the microdetermination of anionic surfactants that was applied to the analysis of 5-100 ppm of sodium dodecyl sulfate and 1-10 ppm of sodium dodecyl ether (2.9 EO) sulfate. This method is based on the inhibitory effect of anionic surfactants on the enzyme system cholinesterase-butyryl-thiocholine iodide. A constant current is applied across two platinum plate electrodes immersed in a solution containing butyrylthiocholine and surfactant. Since cholinesterase produces enzymatic hydrolysis of the substrate, the decrease in the initial velocity of the hydrolysis caused by the surfactant corresponds to its concentration. Amounts up to 60 pg of alcohol sulfate can be spectrometrically determined with acridine orange by extraction of the ion pair with a mixture 3 1 (v/v) of benzene/methyl isobutyl ketone [271]. 

Reaction conditions used for reduction of acridine [430,476, partly hydrogenated phenanthridine [477 and benzo f]quinoline [477 are shown in Schemes 38-40. Hydrogenation over platinum oxide in trifluoroacetic acid at 3.5 atm reduced only the carbocyclic rings in acridine and benzo[h]quinoline, leaving the pyridine rings intact [471]. 

Benzo ring reduction in acridine can be achieved in a variety of ways. 1,4,5,8-Tetrahydro-acridine is given by lithium in liquid ammonia and ethanol (Scheme 35) (69AJC1105). The symmetrical octahydroacridine (48) can be obtained by hydrogenation of acridine over platinum oxide in trifluoroacetic acid. The product is obtained in quantitative yield (Scheme... 

Another report reveals, however, that in vitro DNA-binding assays are insufficient to predict platinum antitumor activity [15]. Primer extension (Fig. 1) was used to identify specific adducts formed by platinum complexes on DNA in HeLa cells. The DNA adduct profile correlated well with in vivo antitumor activity for cis- and trans-DDP, Pt(en)Cl2, and two acridine-tethered platinum complexes. When the complexes were allowed to react with purified DNA in solution, there were no substantial differences in adduct profiles between active and inactive compounds. This result demonstrates that cell-based assays can be better predictors of in vivo activity than in vitro assays, particularly when the in vitro screen does not require aunique, mechanism-based molecular interaction. 

Tetrahydroacridine was hydrogenated to conditions employed. On the other hand, the hydrogenation of acridine over platinum oxide in trifluoroacetic acid leads to quantitative formation of. s-octahydro derivative (eq. 12.52).37... 

Benzo[h]quinoline. In contrast to the case of acridine, the hydrogenation of benzo /t quinolinc over platinum oxide in trifluoracetic acid afforded a mixture of two octahydro derivatives together with a small amount of the 7,8,9,10-tetrahydro derivative, although the octahydro compound hydrogenated in the benzene rings was the major product (eq. 12.56).37... 

Marcoux and Adams have carried out a study of the anodic oxidation of a range of azines in acetonitrile at a platinum electrode.347 With the exception of pyridine which could not be oxidized under these conditions, all the other azines were oxidized in a complicated process in which one electron per molecule was transferred to the electrode. The reaction was investigated in some detail for acridine, and the main product was found to be an acridyl-acridinium perchlorate (perchlorate being supplied by the supporting electrolyte). This result, which is directly comparable with that for pyridine oxidation by peroxydisulfate is persuasive evidence for the mediation of the... 

Hexahydronicotinic acid (90%) is obtained by catalytic hydrogenation of nicotinic acid at 3 atm. pressure over colloidal platinum. Preparation of the catalyst is described. The 9,10 double bond in the acridine nucleus is reduced at 10° by sodium amalgam in dilute sodium carbonate solution to give 9,10-dihydroacridine-S>-carboxylic acid in 70% yield. 2-Phenyl-cyclohexanecarboxylic acid (96%) is prepared by the selective reduction, of 2-phenylbenzoic acid by a large excess of sodium in refluxing amyl alcohol. ... 

Pyrroles may be hydrogenated over a platinum catalyst in acetic acid at 4 atm. and 70° or over a nickel catalyst without solvent at 110 atm. and 180°. N-Substituted pyrroles are more reactive. " " Partial and complete hydrogenation of phenylpyrtoles, phenylindoles, carbazoles, and acridines may be accomplished with either a copper chromite or Raney nickel catalyst. "... 

Acridines, Carbazoles and Other Polycyclic Nitrogen Heterocycles Hydrogenation of acridine (44) in decalin over platinum or palladium catalysts at 150°C and 70 atmospheres of hydrogen gave primarily the 9,10 dihydro product, 45. Over rhodium the fully saturated compound, 46, was obtained (Eqn. 

Fig. 1.8. Structures of Pt complexes linked to intercalators. An acridine orange linked to a platinum—ethylenediamine complex and the proposed structure of a complex with Pt...

The ease of intercalation of other chro-monic and potentially chromonic materials. A number of biochemical reagents, such as acridines and ethidium bromide, intercalate readily between the stacked bases in DNA and RNA. Anticancer drugs, such as the square planar platinum complexes, intercalate avidly (Fig. 14) and naturally occurring antibiotics, such as actinomycin, similarly act by intercalation into the stack of bases [67]. They act as tailor-made spanners in the works and prevent the reading and replication of DNA. 

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