Pradip P. Deohate

Preparation of new series of acridin-9-yl-bis-benzothiazol-2-yl-amines have been developed by intra-molecular cyclization of 1-acridin-9-yl-1-benzothiazol-2-yl-3-aryl thiourea with bromine in acetic acid and evaluated for their in vitro antibacterial activity against Mycobacterium tuberculosis by BACTEC radiometric method. Constitutions of compounds were confirmed by FTIR, 1H-NMR, 13C-NMR spectral methods. Simple work-up procedure and excellent yield of the products are the merits of the route.

A facile synthesis of 1,4-bis-(6-arylimino-[1,2,4]-triazolo-(3,4-b)-[1,3,4]-thiadiazol-3-yl)-benzenes have been carried out by reacting 1,4-bis-(4-amino-3-mercapto-4H-[1,2,4]-triazol-5-yl-benzene with N-aryl isocyanodichlorides followed by the basification with dilute ammonium hydroxide solution. 1,4-bis-(4-amino-3-mercapto-4H-[1,2,4]-triazol-5-yl-benzene was synthesized by the interaction of terephthalic acid dihydrazide with carbondisulphide and potassium hydroxide followed by the addition of hydrazine hydrate. The acetylation of bis-triazolo-dithiadiazines afforded di-acetyl derivatives. The structures of synthesized compounds have been established on the basis of chemical transformation, elemental analysis, equivalent weight determination and IR, 1H-NMR, mass spectral studies. The title compounds have been assayed for their antimicrobial activity against gram-positive as well as gram-negative micro-organisms.

The non-aqueous potentiometric determination of pharmaceutically potent drug aspirin by using isopropyl alcohol as the solvent and alcoholic KOH as the titrant has been carried out. The effect of solvent and concentration on potentiometric determination of aspirin has been studied followed by the estimation of aspirin in single component tablets. The titrations were carried out using glass and calomel electrode pair. The method was found to be convenient for assay of aspirin and results obtained are comparable with those obtained by IP method. Solvent isopropyl alcohol gives much more accurate result as compare to other solvents with minimum % error. In study of effect of concentration, the results obtained are more accurate with positive errors at low concentration whereas, negative errors at high concentration. The error is just +0.11% when 1.804 mg of aspirin was titrated. Confidence level of weight titrated and weight found in respect of aspirin is 0.46 which is statistically non significant.