A novel class of extended pi-conjugated systems: one-pot synthesis of bis-3-aminoimidazo[1,2-a]pyridines, pyrimidines and pyrazines.

Bis-3-aminoimidazo[1, 2-a] pyridines, pyrimidines and pyrazines as extended pi-conjugated systems were synthesized for the first time by a novel pseudo five-component condensation of 2-aminopyridine pyrimidines and pyrazines derivatives with terephthalaldehyde or isoph-thalaldehyde and isocyanides in the presence of p-toluene-sulfonic acid in methanol.

A novel one-pot pseudo-five-component synthesis of 4,5,6,7-tetrahydro-1H-1,4-diazepine-5-carboxamide derivatives.

A novel one-pot pseudo-five-component synthesis of 4,5,6,7-tetrahydro-1 H-1,4-diazepine-5-carboxamide derivatives starting from simple and readily available inputs including 2,3-diaminomaleonitrile, a cyclic or acyclic ketone, an isocyanide, and water in the presence of a catalytic amount of p-toluenesulfonic acid in aqueous medium at ambient temperature in high yields is described.

A novel isocyanide-based three-component reaction: synthesis of highly substituted 1,6-dihydropyrazine-2,3-dicarbonitrile derivatives.

A novel multi-component synthesis of highly substituted 1,6-dihydropyrazine-2,3-dicarbonitrile derivatives starting from simple and readily available inputs is described. Thus, simply stirring an ethanol solution of 2,3-diaminomaleonitrile, a ketone, and an isocyanide in the presence of a catalytic amount of p-toluenesulfonic acid provided highly substituted 1,6-dihydropyrazine-2,3-dicarbonitrile derivatives in good to excellent yields at ambient temperature.

Cellulose sulfuric acid catalyzed one-pot three-component synthesis of imidazoazines.

Imidazoazines have been synthesized by a one-pot three-component condensation reaction of an aldehyde, a 2-aminoazine and an isocyanide in the presence of the cellulose sulfuric acid, as an effective bio-supported catalyst in excellent yields. The reaction work-up is simple and the catalyst can be easily separated from the product and reused in several times.