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A seven-step synthesis of (2E,4E)-5-[4-hydroxy-3-methoxyphenyl]penta-2,4-dienoic acid from ferulic acid was developed. The use of a natural by-product found in rice bran as a raw material provided the ferulic acid vinylogous in an overall high yield. This compound will be useful for the preparation of a wide variety of avenalumic carboxamide derivatives.

Imidazobenzodiazepine derivatives were obtained by cyclization of the condensation products 7‐amino‐2,5,6‐trimethylbenzimidazole with acetylacetone and ethyl acetoacetate. By careful examination of spectroscopic data and the open‐chain intermediate isolation, we have identified the formed compound structure.

6- and 7-(4-hydroxy-6-methyl-2-oxo-1-pyridyl)benzimidazoles and 1-(6- and 7-benzimidazolyl)-4-hydroxy-2-oxoquinolines were synthesized by reaction of aminobenzimidazoles with 4-hydroxy-6-methyl-2-pyrone and 4-hydroxycoumarine.

Halogenation of 2-alkyl-5(6)-chloro(ormethyl)benzimidazoles occurs in 6(5) position and subsequent nitration affords the corresponding 7(4)-nitrobenzimidazoles.

We have examinated the addition of 7-aminoindoles with acetylacetone and we have shown by careful examination of spectroscopic data that this reaction does not lead to the previously described diazepinoindole.