Issue 15, 1977

C-nucleoside studies. Part 6. Synthesis of 3-[2,3,5-tri-O-benzyl-β-(and α)-D-ribofuranosyl]prop-2-yn-1-ol and related compounds; a new synthesis of 3(5)-(2,3,5-tri-O-benzyl-β-D-ribofuranosyl)pyrazole

Abstract

Treatment of 2,3,5-ri-O-benzyl-β-D-ribofuranosylethyne (2) with a large excess of paraformaldehyde and potassium hydroxide in ethanol gave 3-(2,3,5-tri-O-benzyl-β-D-ribofuranosyl)prop-2-yn-1-ol (5) in 70% yield. Oxidation of (5) with chromic oxide (Jones reagent) afforded the carboxylic acid (4)(75%), esterification of which with diazomethane gave the known ester (7). Similar reactions and correlations have been carried out in the α-series.

Reaction of the Grignard reagent (14) of 3-(tetrahydropyran-2-yloxy)propyne with 2,3,5-tri-O-benzyl-D-ribofuranose (19) followed by ring closure and removal of the tetrahydropyranyl ether group gave the alcohol (5) in 52% overall yield.

Careful oxidation of (5) gave the corresponding aldehyde (3) which yielded the known pyrazole (1)(72%) on treatment with hydrazine. When 1,2-dideoxy-4,5:7,8-di-O-isopropylidene-D-manno-oct-1-yn-3-ulofuranose (22) was treated with hydrazine, 3(5)-(1,2:4,5-di-O-isopropylidene-D-manno-pentahydroxypentyl)pyrazole (23) was isolated in 93% yield.

Article information

Article type
Paper

J. Chem. Soc., Perkin Trans. 1, 1977, 1786-1791

C-nucleoside studies. Part 6. Synthesis of 3-[2,3,5-tri-O-benzyl-β-(and α)-D-ribofuranosyl]prop-2-yn-1-ol and related compounds; a new synthesis of 3(5)-(2,3,5-tri-O-benzyl-β-D-ribofuranosyl)pyrazole

J. G. Buchanan, A. D. Dunn, A. R. Edgar, R. J. Hutchison, M. J. Power and G. C. Williams, J. Chem. Soc., Perkin Trans. 1, 1977, 1786 DOI: 10.1039/P19770001786

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements