the synthesis of aryl amides via the reactions of carboxylic acids and isocyanides in methanol was carried out in 78-95% yields under ultrasound irradiation. the method has wide applicability, and the protocol is mild, fast and efficient compared to the existing methods based on silent conditions.

2-Aminobenzothiazole-6-carboxylic acid (1), on condensation with chloroacetyl chloride yielded 2-(2-chloroacetylamino)benzothiazole-6-carboxylic acid (2), which on amination with hydrazine hydrate yielded in turn 2-(2-hydrazinoacetylamino)benzo-thiazole-6-carboxylic acid (3). Compound 3, on condensation with various aromatic aldehydes afforded a series of 2-{2-[N'-(arylidene)hydrazino]acetylami...

Alkylation of pyrazine-2-carboxylic acid and 6-chloropyrazine-2-carboxylic acid with radicals generated by silver nitrate-catalyzed oxidative decarboxylation of pivalic acid afforded 5-(1,1dimethylethyl)pyrazine-2-carboxylic acid and 6-chloro-5-(l,l-dimethylethyl)pyrazine-2-carboxylic acid. Condensation of chlorides of the latter three halogenated and/or alkylated pyrazine-2carboxylic acids wit...

We developed an ion-exclusion/adsorption chromatography (IEAC) method employing a polystyrene-divinylbenzene-based weakly acidic cation-exchange resin (PS-WCX) column with propionic acid as the eluent for the simultaneous determination of multivalent aliphatic carboxylic acids and ethanol in food samples. The PS-WCX column well resolved mono-, di-, and trivalent carboxylic acids in the acidic e...

1 The isolated spinal cord of the frog (Rana pipiens) was used to examine the structural requirement for the activity of neutral amino acids. The potencies of the aliphatic amino acids, gamma-aminobutyric acid (GABA), beta-alanine and glycine were compared with the potencies of conformationally restricted cyclopentane and cyclohexane amino acid analogues. Both motoneurone hyperpolarizing and pr...

n-(diphenylphosphino)triethyl- and tributylammonium salts are introduced as easily prepared, cheap and stable ionic liquids that act as the condensing agent and media for the efficient esterification of acids with alcohols and phenols. this class of ionic liquids is immiscible with the ester products and thus allows simple and easy separation of the desired products from the reaction mixture.

toxicity of 38 aliphatic carboxylic acids was studied using non-linear quantitative structure-toxicityrelationship (qstr) models. the adaptive neuro-fuzzy inference system (anfis) was used to construct thenonlinear qstr models in all stages of study. two anfis models were developed based upon differentsubsets of descriptors. the first one used log ow k and lumo e as inputs and had good predicti...