Formazan benzothiazolyl

Other transition metals have received much less attention. Complexes of palladium and 2-amino-phenyl-containing formazans have been reported.397 Mercury complexes of tridentate formazans have been studied.398 Silver complexes of tridentate benzothiazolyl-containing formazans have also been studied.399 Recently, alkali and alkaline earth metals have been the subject of many studies. Formazans such as 228 and 229 as well as the macrocyclic 204 have received considerable attention as metal-specific analytical reagents.400-41 1... 

Tables 15 and 16 show the absorption maxima of some metal complexes of benzothiazolyl-substituted formazans 230 and 231.283 The wavelengths are metal ion dependent, making formazans useful reagents for the identification of specific metal ions or the simultaneous determination of two ions. The wavelengths are much longer than those of the formazan anion (Table 14). The general trend for electron-rich substituents is toward a larger shift this is to be expected as it tends to enhance the aromatic character of the ring and increase the covalent character of the metal — nitrogen bond. The sharpness of the absorption band has been attributed to coordination to the heterocyclic nitrogen as in 232.57S...

Endothelial cells of brain arteries, veins and capillaries of the Wistar rat showed a positive NADPH-diaphorase (EC 1.6.99.1) reaction in form of 2-(2 -benzothiazolyl) - 5 - styryl - 3 - (4 - phthal - hydrazidyl) tetrazolium chloride-formazan contrast at the nuclear envelope, membranes of mitochondria and endoplasmic reticulum (Stanarius et al. 1997). Endothelial nitric oxide synthase (EC 1.14.23) immu-nostaining without tyramide signal amplification yielded electron dense 3,3 -diaminobenzidine precipitates that were seen in the endothelium if arteries, veins and some capillaries. Its pattern corresponded roughly with the membrane-bound 2-(2 -benzothiazolyl) - 5 - styryl - 3 - (4 - phthal-hydrazidyl) tetrazolium chloride-formazan deposits generated by NADPH-diaphorase. 

Benzothiazolyl)-3-(2-hydroxyphenyl)-1-phenylformazan, B-00103 5-Benzothiazolyl-3-(2-methoxyphenyl)-1 -phenylformazan, in B-00103 5-(2-Benzothiazolyl)-3-methyl-1 -phenylformazan, B-00105 5-(2-Benzothiazolyl)-1 -(4-nitrophenyl)-3-phenylformazan, B-00106 l-(2-Benzothiazolyl)-3-phenyl-5-(4-sulfophenyl)formazan Na salt, in B-00108... 

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