The thio- and selenocyanation of quinone monoimines of pyrido[1,2-a]benzimidazole series with the participation of dithiocyanogen and triselenodicyanide in mild reaction conditions results in formation of 9- or 6-thiocyano- and 9-selenocyano- derivatives in good yields.

The oxidative coupling of primary aliphatic and aromatic amines with 3,4,4a,5-tetrahydropyrido[1,2-a]-benzimidazole derivatives resulted in the formation of p-quinone diimines of the given series.

Reactions of some 1,5-diketones with 2-aminobenzyl alcohol and 2-aminomethylaniline follow double cyclization scheme with formation of pyridobenzoxazine and pyridoquinazoline derivatives, respectively. Oxidative coupling of the cyclization products with CH acids occurs at the 4-position of the pyridine ring.