Linked Life Data

12027686

Source:http://linkedlifedata.com/resource/pubmed/id/12027686

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2002-5-24
pubmed:abstractText
We report herein a short stereocontrolled synthesis of heterocyclic C-nucleosides (indole, imidazole, benzimidazole, and 6-iodobenzimidazole). First, condensation of 2-lithiated heterocycles 2-5 with 5-(tert-butyldiphenylsilyl)-2,3-O-isopropylidene-D-gamma-ribonolactone (1) afforded the hemiacetals 6-9 in good yields. Then, borohydride reduction (NaBH(4)) of the protected hemiacetals proceeded stereoselectively to give predominantly the S diols 10-13, which upon Mitsunobu cyclization afforded the alpha-C-nucleosides 14-17. In contrast, the same PPh(3)/DEAD treatment of the 1:1 diastereomeric mixture of the free heterocyclic diols 10d and 11d gave exclusively the beta-anomers 14dbeta and 15dbeta, respectively, by a stereocontrolled process. The mechanisms of these stereocontrolled steps are discussed with the support of molecular modeling studies.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-3263
pubmed:author
pubmed:issnType
Print
pubmed:day
31
pubmed:volume
67
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3724-32
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Stereocontrolled synthesis of heterocyclic C-nucleosides. Protecting group effect and molecular modeling studies.
pubmed:affiliation
Institut de Chimie des Substances Naturelles, CNRS, Avenue de la Terrasse, 91198 Gif-Sur-Yvette, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't