Welcome to LookChem.com Sign In|Join Free

Article Doi

C-Nucleoside Studies. Part 14. A New Synthesis of Pyrazofurin

DOI: 10.1039/P19810002374

Source and publish data:

Journal of the Chemical Society. Perkin transactions I p. 2374 - 2378 (1981)

Update date:2022-08-04

Topics:

Authors:

Buchanan, J. GrantBuchanan, J. Grant

Stobie, AlanStobie, Alan

Wightman, Richard H.Wightman, Richard H.

Read Full Text PDF DownLoad Join now for total 90,000,000 free articles

Article abstract of DOI:10.1039/P19810002374

Treatment of 3-cyano-4-nitro-5-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)pyrazole (4) with benzyl bromide and triethylamine gave as major product the 1-benzyl-5-cyano-isomer (5), whilst similar treatment of 5-cyano-3-methyl-4-nitropyrazole (7) gave exclusively 1-benzyl-3-cyano-5-methyl-4-nitropyrazole (8).This was converted into 4-amino-1-benzyl-3-carboxamido-5-methylpyrazole (10); attempts to convert (10) into a 4-hydroxypyrazole via the diazonium salt were unsuccessful, but photolysis of the diazonium salt (11) in aqueous trifluoroacetic acid-dioxan gave 1-benzyl-3-carboxamido-5-methylpyrazole (13) in 67percent yield.Treatment of 4-amino-3-cyano-5-methylpyrazole (14) with nitrous acid and subsequent neutralisation gave a diazopyrazole which on photolysis in aqueous acetone yielded 3-cyano-4-hydroxy-5-methylpyrazole (16) in 79percent overall yield.Application of the same sequence to 4-amino-3-cyano-5-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-pyrazole (2) gave the 4-hydroxy-compound (17) (87percent overall), which was converted in two steps into pyrazofurin (1).

View More

Products guided by the article

Product name:1-benzyl-3-cyano-5-methyl-4-nitropyrazole

Cas No:79263-98-2

79263-98-2

R&D Labs maybe for 79263-98-2

Relevant to this article

Hot Product