Efficient routes to pyrazolo[3,4-e][1,2,4]triazines and a new ring system: [1,2,4]triazino[5,6-d][1,2,3]triazines.

SYNTHESIS AND STRUCTURE ELUCIDATION OF 1,2,4-TRIAZINO [4,3-b] 1,2,4-TRIAZINES, 1,2,4-TRIAZINO [3,4-C] 1,2,4-TRIAZINES AND 1,2,4-TRIAZINO [4,3-dl l,2,4-TRIAZINES

Ring Cleavage of Some Bicylic Compounds Derived from 1,2,4-Triazine

Ring cleavage occurred when 1,2,4-triazino-1,2,4-triazines (3), (4) and (5) were treated with concentrated hydrochloric acid to yield N-substituted triazines (7) and (8). These confirm the given configuration assigned to the isomeric triazinotriazines. 6-Methyl-2-phenyl-7H-oxazolo [3,2-b][1,2,4]-triazin-7-one (9) underwent ring cleavage on treatment with sodium alkoxide to afford 3-alkoxy-1...

Ring Transformation of Oxazolo [3,2-b][1,2,4] Triazines

6-Methyl-2-phenyl-7H-Oxazolo [3,2-b] [1,2,4] triazine (1) undersent ting transformation on treatment with ammonia and primary amines to afford the corresponding imidazol [1,2-b][1,2,4] triazine (2). Treatment of (1) with hydrazine hydrate gave the corresponding 3-aryl-4H-1,2,4- triazino [4,3-b][1,2,4] triazin-8 (1H)-one (3).

Microwave assisted synthesis of some new fused 1,2,4-triazines bearing thiophene moieties with expected pharmacological activity.

Rapid and efficient solvent-free synthesis of 4-amino-3-mercapto-6-[2-(2-thienyl)vinyl]-1,2,4-triazin-5(4H)-one 1 under microwave irradiation is described. Some new fused heterobicyclic nitrogen systems such as 1,2,4-triazino[3,4-b][1,3,4]thiadiazinones, 1,3,4-thiadiazolo[2,3-c][1,2,4]triazinone and pyrazolo[5,1-c]-[1,2,4]triazine-7-carbonitrile, have been synthesized by treatment of 1 with bif...

A CONVENIENT AND GENERAL SYNTHESIS OF THIADIAZOLO [2,3-C] [1,2,4] TRIAZINES

Condensation and cyclization of 5-hydroxy- 1,2,4- thiadiazol-2-yl hydrazine 1 with pyruvic acid, phenacyl bromide, propargyl bromide and ally1 bromide afforded compounds 2,5,7 3, 4 ,6 and 8 respectively, Reaction of 1 with epichforohydrine afforded 4-hydroxy-N-[5-hydroxy- 1 ,3,4-thiadiazoly1] pyrazolidine 9