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Cyclization of amino acid hydrazide afforded a new class of heteroatom activated β-lactams. These compounds are potent parent nuclei which possess significant biological activity

The ir spectrum of imidazole derivatives, which have an alkoxycarbonyl group and a carboxamide group at the 4- and 5-positions of the imidazole ring respectively, exhibits the shift of the ester carbonyl band to a lower wave number. This phenomenon was investigated by spectroscopic measurements of a group of relevant compounds. The results indicate that the shift is caused by the intramolecular hydrogen bonds between the hydrogen atom of the amide and the carbonyl oxygen of the ester which is enhanced by the resonance stabilization of the imidazole ring.

A convenient general method for the synthesis of unsymmetrical imidazole-4,5-dicarboxylic acid derivatives is described. The key intermediates are 5,10-dioxo-5H,10H-diimidazo[1,5-a:1′,5′-d[pyrazine-1,6-dicarboxylic acid, -1,6-dicarboxylic ester and -1,6-dicarboxamide.

Novel 1,3-dithiolan-2-one derivatives were prepared starting from α, β- or β, γ-dichlorinated carboxylic esters and potassium O-ethyl dithiocarbonate. The scope and the mechanism of this reaction were investigated. The biological uses of the compounds obtained here were examined.

Imidazolecarboxamide derivatives have been known to exhibit biological activity, especially antiparasitic activity.1 To date imidazole-4(5)-monocarboxamide derivatives and symmetrical imidazole-4,5-dicarboxamide derivatives have been investigated.1 However, unsymmetrical imidazole-4,5-dicarboxamide derivatives, having different carboxamide groups, have not been investigated. Therefore, the author was prompted to devise a synthetic method for unsymmetrical diamide derivatives.

The ir spectrum of imidazole derivatives, which have an alkoxycarbonyl group and a carboxamide group at the 4- and 5-positions of the imidazole ring respectively, exhibits the shift of the ester carbonyl band to a lower wave number. This phenomenon was investigated by spectroscopic measurements of a group of relevant compounds. The results indicate that the shift is caused by the intramolecular hydrogen bonds between the hydrogen atom of the amide and the carbonyl oxygen of the ester which is enhanced by the resonance stabilization of the imidazole ring.