2, 2′‐Anhydro‐1‐(3′, 5′‐di‐O‐acetyl‐β‐D‐arabinofuranosyl)uracil, a cyclouridine nucleoside with a C4′‐endo furanosyl conformation. (13th February 2013)

• Record Type: Journal Article
• Authors: Fu, Ying; He, Yin‐Xia; Hou, Hong‐Xia; Zhu, Wen‐Bo; Li, Hu‐Lin; Wu, Chao; Xian, Fang‐Yan
• Is Part Of: Acta crystallographica. Volume 69:Part 3(2013:Mar.)
• Page Start: 282
• Page End: 284
• Publication Date: 2013-02-13
• Subjects: Crystallography -- Periodicals; Crystals -- Periodicals; 548.05
• DOI: 10.1107/S0108270113000395
• Languages: English
• ISSNs: 0108-2701

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>2, 2′‐Anhydro‐1‐(3′, 5′‐di‐<italic>O</italic>‐acetyl‐β‐D‐arabinofuranosyl)uracil, C₁₃H₁₄N₂O₇, was obtained by refluxing 2′, 3′‐<italic>O</italic>‐(methoxymethylene)uridine in acetic anhydride. The structure exhibits a nearly perfect C4′‐<italic>endo</italic> (⁴<italic>E</italic>) conformation. The best four‐atom plane of the five‐membered furanose ring is O—C—C—C, involving the C atoms of the fused five‐membered oxazolidine ring, and the torsion angle is only −0.4 (2)°. The oxazolidine ring is essentially coplanar with the six‐membered uracil ring [r.m.s. deviation = 0.012 (5) Å and dihedral angle = −3.2 (3)°]. The conformation at the exocyclic C—C bond is <italic>gauche–trans</italic> which is stabilized by various C—H...π and C—O...π interactions.</p> </abstract>