Condensed 1,2,4‐Triazines, III

Alkylation of 3‐mercaptophenanthreno[9,10‐ e ]‐1,2,4‐triazine ( 1b ) yielded the S ‐alkyl derivatives 2 a‐d . Amination of 1a afforded the 3‐amino derivatives 3a‐h . Reaction of 1a with hydrazine hydrate gave 3‐hydrazinophenanthreno[9,10‐ e ]‐1,2,4‐triazine ( 4 ) which underwent cyclisation with nitrous, formic or acetic acids giving the phenanthreno[9,10‐ e ]‐1,2,4‐triazino[2,3‐d]‐1,2,3,4‐tetrazole ( 5 ) and the phenanthreno[9,10 e ]‐1,2,4‐triazino[2,3‐ d ]‐3 H ‐methyl‐1,2,4‐triazoles 6, 7 . Compound 4 also reacted with methyl [bis(dimethylmercapto)methylene]cyanoacetate, ethyl acetoacetate, ethoxymethylenemalononitrile, ethyl ethoxymethylencyanoacetate or acetyl acetone to yield the 3‐(pyrazol‐1‐yl)‐phenanthreno[9,10‐ e ]‐1,2,4‐triazines 8–12 .