Download PDF
Synthesis 2010(8): 1303-1310  
DOI: 10.1055/s-0029-1218677
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

A Synthetic Route to Fully Substituted Chiral Cyclopentylamine Derivatives: Precursors of Carbanucleosides

Ramprasad Ghosha, Joy Krishna Maitya, Michael G. B. Drewb, Basudeb Acharia, Sukhendu B. Mandal*a
a Chemistry Division, Indian Institute of Chemical Biology (a unit of CSIR), Jadavpur, Kolkata 700 032, India
Fax: +91(33)24735197; e-Mail: sbmandal@iicb.res.in;
b Department of Chemistry, University of Reading, Whiteknights, Reading, RG6 6AD, UK
Further Information

Publication History

Received 21 December 2009
Publication Date:
11 February 2010 (online)

   Buy Article Permissions and Reprints All articles of this category
Zoom Image

Abstract

Removal of silyl protection from d-glucose derived substrate 6 afforded 7, which upon acetonide deprotection followed by reaction with N-benzylhydroxylamine furnished two isomeric isoxazolidinocyclopentane derivatives via spontaneous cyclization of an in situ generated nitrone. The methyl xanthate derivative of the tertiary hydroxyl group of one isomer was isolated and subjected to radical deoxygenation reaction to form epimeric products, while with the other isomer it underwent spontaneous 1,2-elimination to form a mixture of the two possible endocyclic olefins. Hydrogenolytic cleavage of the isoxazolidine rings of the purified products followed by insertion of 5-amino-4-chloropyrimidine moiety and purine ring construction smoothly afforded structurally unique carbanucleoside analogues. Various spectroscopic methods on the synthesized compounds and X-ray analysis on one important intermediate were used to assign the structures and stereochemistry of the products.

Key words

cyclopentylamine - INC reaction - carbanucleosides - d-glucose