Spin Labeled Nucleoside Analogues: 4′-Hydroxymorpholin-2′-Ylpurines and Pyrimidines
- 1 July 1993
- journal article
- research article
- Published by Taylor & Francis in Nucleosides and Nucleotides
- Vol. 12 (6), 615-629
- https://doi.org/10.1080/07328319308019016
Abstract
Upon borane-pyridine reduction, a series of nucleoside dialdehyde dioximes 2 underwent cyclization to the corresponding 4′-hydroxymorpholin-2′-ylpurines or pyrimidines 3 from which the peracetyl derivatives 4 were prepared. At room temperature, compounds 3 and 4 exist as a mixture of invertomers in which the 4′S (equatorial 4′-OH or 4′-OAc) predominates. A 14 kcal/mol, nitrogen inversion barrier was estimated from variable temperature experiments. N.O.E. and 3JCH measurements established the anti conformation of the base-“sugar” bond. Compounds 3 spontaneously oxidized to the corresponding aminoxyl free radicals, EPR spectra of which showed that they existed in a chair conformation.Keywords
This publication has 19 references indexed in Scilit:
- Molecular mechanical parameters (MM2 force field) for the N(sp3)-O(sp3) bondInternational Journal of Biological Macromolecules, 1993
- Synthesis and Anti-HIV Activity of a New Hexopyranoside Analogue of AZTNucleosides and Nucleotides, 1992
- New types of spin-labelled sugar and nucleoside analogs: Pyrrolidine, morpholine and piperidine N-OxylsTetrahedron Letters, 1991
- Macromodel—an integrated software system for modeling organic and bioorganic molecules using molecular mechanicsJournal of Computational Chemistry, 1990
- Radicaux libres dérivés de sucres. V. Dérivés d'osamines N‐hydroxylées et composés voisins Communication préliminaireHelvetica Chimica Acta, 1982
- Untersuchungen zur struktur perjodatoxydierter ribonucleoside und ribonucleotideCarbohydrate Research, 1977
- Structural studies by nuclear magnetic resonance—XIXTetrahedron, 1968
- Nuclear Magnetic Resonance Methods for Determining Chemical-Exchange Rates1Journal of the American Chemical Society, 1966
- The Conformational Preference of the Nonbonding Electron Pair in PiperidineJournal of the American Chemical Society, 1966
- Nuclear Spin Coupling Between Geminal Hydrogen AtomsThe Journal of Chemical Physics, 1965