Anti-azobenzene

Immunochemical studies should prove especially useful for non radiolabeled chemicals. As regards our anti azobenzen-DNA-antibodies, they could not be characterized in as great detail as for the anti-ANQO-DNA and anti-DMAB-DNA-antibodies, because radiolabeled compounds are not available, and the chemical nature of the relevant adducts has not yet been elucidated. However, these antibodies were found to react specifically with A-aminoazobenzene-modified DNA and immunostaining was observed in the nuclei of hepatocytes of rats treated with 3-methoxyl-AAB. 

Armstrong et al. [62] used a-cyclodextrin (R = H) and /8-cyclodextrin derivatives (R = hydroxypropyl) [63] as additives in the mobile phase for the separation of different diastereoisomers. Thus, they separated 5yn-azobenzene Rp = 0.09) from anti-azobenzene (Rp = 0.53) on polyamide or polyamide with fluorescent indicator adding a-cyclodextrin to the mobile phase (0.1 M) [62] or some steroid epimers and alkaloids on plates coated with chemically bonded octadecylsilane reversed-phase [62]. The used mobile phases obtained by adding hydroxypropyl-/8-cyclodextrin are presented in Table 8.9, beside the chromatographic results. 

An example of a compound of the -N=N- structure and showing geometrical isomerism is the syn and anti form of the azobenzene. 

Ortruba III, j. P., and Weiss, R. G. (1983). Liquid crystalline solvents as mechanistic probes. 11. The syn —> anti thermal isomerization mechanism of some low- bipolarity azobenzenes. /. Org. Chem. 48, 3448-3453. 

In the second experiment, the diastereomers (geometric isomers) (Sec. 7.1) syn-azobenzene (1) and fl fi-azobenzene (2) are separated. Commercially available azobenzene consists predominantly of the more-stable anti- form, but this isomer may be isomerized to the less-stable syn- isomer by irradiation with ultraviolet light or sunlight. Since the colors of the two isomers differ, they may be detected visually. The course of the reaction and the effectiveness of the irradiation is followed by placing spots of irradiated and nonirradiated samples side by side on the TLC strip. 

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