5334-36-1

Upstream product

• 28668-15-7 3⁽⁵⁾-cyano-5⁽³⁾-methyl-4-nitropyrazole 
• 94827-20-0 3-cyano-5-methyl-4-nitro-1-(tetrahydropyran-2-yl)-1H-pyrazole 
• 5334-38-3 3-methyl-4-nitropyrazole-5-carboxylic acid 
• 80030-73-5 2,7-dimethyl-3,8-dinitrodipyrazolo[1,5-a;1',5'-d]pyrazine-4,9-dione 
• 28668-07-7 ethyl 3-methyl-4-nitro-1H-pyrazole-5-carboxylate 
• 94827-21-1 3-carbamoyl-5-methyl-4-nitro-1-(tetrahydropyran-2-yl)-1H-pyrazole 

Downstream Products

• 28668-16-8 4-amino-5-methyl-1H-pyrazole-3-carboxamide 
• 5399-98-4 dimethyl-(3-methyl-1(2)H-pyrazolo[4,3-d]pyrimidin-7-yl)-amine 
• 5399-94-0 3-methyl-7-oxo-6,7-dihydro-1H-pyrazolo<4,3-d>pyrimidine 
• 5399-96-2 3-methyl-1,6-dihydro-pyrazolo[4,3-d]pyrimidine-7-thione 
• 28668-19-1 3-Methylpyrazolo<4,3-d>pyrimidin-5,7-dion 
• 77816-07-0 3-methyl-1(2)H-pyrazolo[4,3-d]pyrimidine 
• 7057-22-9 7-Amino-3-methylpyrazolo<4,3-d>pyrimidin 
• 5399-95-1 7-chloro-3-methyl-1H-pyrazolo<4,3-d>pyrimidine 

Relevant academic research and scientific papers

C-Nucleoside Studies. Part 17. The Synthesis of 3(5)-Carbamoyl-5(3)-β-D-ribofuranosylpyrazole (4-Deoxypyrazofurin) and 4-Amino-3(5)-carbamoyl-5(3)-β-D-ribofuranosylpyrazole

4-Amino-3(5)-cyano-5(3)-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)pyrazole (10) was converted into the diazopyrazole (11) by treatment with nitrous acid.On photolysis in aqueous dioxane using visible light compound (11) gave 3(5)-cyano-5(3)-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)pyrazole (12) which formed the corresponding amide (13) (75percent) with alkaline hydrogen peroxide.Deprotection of compound (13) with methanolic ammonia afforded 3(5)-carbamoyl-5(3)-β-D-ribofuranosylpyrazole (4) (74percent), the 4-deoxy analogue of pyrazofurin (3). 3(5)-Cyano-4-nitro-5(3)-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)pyrazole (1) reacted with dihydropyran and toluene-p-sulphonic acid to give the N-tetrahydropyranyl) derivative (21) (66.5percent).Hydrolysis of the nitrile group of compound (21), using alkaline hydrogen peroxide, afforded the amide (22) (71percent) which was deprotected to give 3(5)-carbamoyl-4-nitro-5(3)-β-D-ribofuranosylpyrazole (23) (83percent).Catalytic reduction of compound (23) gave 4-amino-3(5)-carbamoyl-5(3)-β-D-ribofuranosylpyrazole (5) (83percent) which could be converted into formycin B (24) (69percent).

Synthesis for 7-alkylamino-3-methylpyrazolo [4,3-d]pyrimidines

An improved synthesis is disclosed for 7-alkylamino-3-methylpyrazolo[4,3-d]pyrimidines, which are known to be potent cytokinin antagonists.