2‐Methyl‐3‐nitrochromone (1) reacted with acid hydrazides, S‐methylisothiourea, hydroxylamine and ethyl aminoethanoate to give the nitro derivatives of pyrazole 2, pyrimidine 6, isoxazole 11 and pyrrole 13, respectively. These nitro compounds were reduced by catalytic hydrogenation to the corresponding amino derivatives. In the case of 2, a rearrangement of the acyl group took place during the reduction. Substitution reactions of the 2‐methylthio group in 6 were also described.

Novel 3‐quinoxalinyl‐1,5‐benzodiazepines 4, 5, 6, 9, 10 were synthesized via the ring transformation of 3‐(N,N‐dimethylcarbamoyl)furo[2,3‐b]quinoxaline hydrochloride (1). The 3‐quinoxalinyl‐1,5‐benzodiazepine hydrochlorides 4 and 6 are the tautomers of the N1′‐H (or N5‐H) form and the C3‐H form, respectively, which are stable in solid and solution. However, 4 (NH form) was found to be converted into 6 (C3‐H form) by refluxing in acetic acid. The individual spectral evidences and different reactivity of these tautomers are described.

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