Synthesis, characterization and biological activity of some 1,2,4‐triazine derivatives

Abstract

Abstract 4‐Amino‐6‐methyl‐3‐(2 H )‐thioxo‐5‐(4 H )‐oxo‐1,2,4‐triazine ( 1 ) was condensed with 2‐methyl (or phenyl)‐4 H ‐3,1‐benzoxazin‐4‐one ( 5a,b ) in boiling acetic acid to give compounds 8‐11 . Reacting 1 with chloroacetyl chloride afforded the corresponding chloroacetamido and triazinothiadiazine derivatives 12 and 13 . Condensing 2 with succinic anhydride and/or phthalic anhydride yielded compounds 14 and 15 . Benzoylation of 4‐amino‐6‐methyl‐3‐(2 H )‐thioxo‐5‐(4 H )‐oxo‐2‐(2,3,4,5‐tetra‐ O ‐acetyl‐α‐D‐glucopyra‐nosyl)‐1,2,4‐triazine ( 19 ) afforded the corresponding 4‐ N,N ‐dibenzoyl derivative 20 . Deblocking of the N ‐2 glycoside 21 and the S ‐glycoside 22 by methanolic ammonia gave compounds 23 and 24 . Acetylation of 4‐amino glycoside 25a afforded the corresponding 4‐mono‐ and 4‐diacetyl derivatives 26 and 27 . Deamination of 25a,b yielded compounds 28a,b . Methylation of compound 28b afforded the corresponding N 4‐ and S ‐methyl derivatives 29 and 30 .