90558-96-6

Upstream product

• 61-82-5 3⁽⁵⁾-amino-1,2,4-triazole 
• 3788-94-1 2-ethoxymethylene-3-oxobutanoic acid ethyl ester 
• 66373-46-4 2-hydrazino-4-methyl-pyrimidine-5-carboxylic acid ethyl ester 
• 122-51-0 orthoformic acid triethyl ester 
• 100378-15-2 4-methyl-2-nitroamino-pyrimidine-5-carboxylic acid ethyl ester 
• 61-82-5 3-amino-1,2,4-triazole 

Downstream Products

• 42399-86-0 7-Methyl-s-triazolo<1,5-a>pyrimidin 
• 102170-06-9 7-methyl-[1,2,4]triazolo[1,5-a]pyrimidine-6-carboxylic acid 
• 1248517-85-2 7-hydroxy-6,7-dihydropyrido[3,4-e][1,2,4]triazolo[1,5-a]pyrimidin-6-one 
• 1235515-22-6 (E)-7-(2-dimethylaminovinyl)-6-ethoxycarbonyl[1,2,4]triazolo[1,5-a]pyrimidine 
• 932736-65-7 6-acetyl-7-hydroxy-1,2,4-triazolo[1,5-a]pyrimidine 

Relevant academic research and scientific papers

2-R-7-methyl[1,2,4]triazolo[2,3-a]pyrimidines: Synthesis and structures

Reactions of 5-R-3-amino-1,2,4-triazoles with ethoxymethylideneacetylacetone and ethyl ethoxymethylideneacetoacetate proceeded regioselectively, giving 2-R-7-methyl[1,2,4]triazolo[2,3-a]-pyrimidines in good yields. The compounds obtained were characterized by elemental analysis, 1H NMR spectroscopy, and X-ray diffraction analysis (for ethyl 2-ethylthio-7-methyl[1,2,4]triazolo[2,3-a]pyrimidine-6-carboxylate). The frontier orbitals, the molecular electrostatic potential, and the geometries of the reagent molecules were calculated by the DFT method (B3LYP/6-31G* *).

Recyclization of condensed carbethoxypyrimidines accompanied by substitution of a carbon atom into the heterocycle

Condensation in ethanol of ethyl ethoxymethyleneacetoacetate with systems containing an amidine fragment (substituted 3-aminopyrazoles and 3-amino-1,2,4-triazole) gave 6-carbethoxy-7-methylpyrazolo[1,5-a]pyrimidines. Addition of base to solutions of the o