478189-75-2

Upstream product

• 31523-22-5 3-hydrazino-5H-[1,2,4]triazino[5,6-b]indole 
• 140230-04-2 3-[(Z)-3-Amino-5-methyl-[1,2,4]triazol-4-ylimino]-1,3-dihydro-indol-2-one 
• 21532-07-0 3,4-diamino-5-methyl-1,2,4-triazole 
• 91-56-5 indole-2,3-dione 
• 64-19-7 acetic acid 
• 140230-18-8 10-acetyl-3-methyl-1,2,4-triazolo[4,3-b]1,2,4-triazino[5,6-b]indole 
• 73214-26-3 3,4-diamino-1,2,4-triazol-5-methyl hydrochlorid 
• 478189-76-3 5-acetyl-3-acetylhydrazino-1,2,4-triazino[5,6-b]indole 
• 140229-97-6 N-Eth-(E)-ylidene-N'-(5H-[1,2,4]triazino[5,6-b]indol-3-yl)-hydrazine 

Relevant academic research and scientific papers

Synthesis of substituted pyrazino[5,6-b]pyrimidine and some indole derivatives

Refluxing dimethyl acetylenedicarboxylate (DMAD) or 1,2-dibenzoylacetylene with isatin-3-thiosemicarbazone or isatin-3-thiocarbohydrazone in methanol produced 3-substituted oxindoles in good yields. Reaction of equimolecular amounts of 5,6-diamino-urasil-

Reinvestigation of the regiospecific outcome of heterocyclization of 3-hydrazino-1,2,4-triazino[5,6-b]indoles: Angular versus linear annelated 1,2,4-triazolo-1,2,4-triazino[5,6-b]indole structures

Divergences of the structural assignments reported in the literature for the products of cyclization of 3-hydrazino-1,2,4- triazino[5,6-b]indoles 1 with one-carbon cyclizing reagents have been reinvestigated. The linear annelated 1,2,4-triazolo[4,3-b] 1,2,4-triazino[5,6-b]indoles 3 were found to be the products regiospecifically formed, rather than the angular annelated 1,2,4-triazolo[3,4-c] 1,2,4-triazino[5,6-b]indoles 2. Our findings were based on comparison of the UV spectral data of the cyclization products with those of unequivocally as well as inevitably linear annelated compounds. Calculations of optimized geometries and electronic structures accord with the results obtained. Divergences reported in the literature were, therefore, attributed to erroneous structural assignments rather than to cyclization by different regiochemical pathways.