5-(4-Ammonio-2-Oxopyrimidine-1(2H)-yl)-1,3-Oxathiolane-2-Carboxylate (lamivudine acid) Semihydrate: The Six-Fold Symmetry Created by Hydrogen Bond Network
作者:Grzegorz Dutkiewicz、C. S. Chidan Kumar、H. S. Yathirajan、B. Narayana、Maciej Kubicki
DOI:10.1007/s10870-010-9866-8
日期:2011.2
The title compound, C8H9N3O4S × 1/2(H2O), which is an impurity found in a drug lamivudine, crystallizes in the hexagonal space group P62 with a = 10.208(1) Å and c = 18.073(2) Å. Such a rare packing is constructed by the hierarchical network of hydrogen bonds, which connect the molecules into chains, then into pairs of chains, and neighboring chains, oriented at the angle of 60°, make the final packing mode. The molecule exists in the crystal as the zwitterion, with negative charged carboxylate and positive ammonio groups. The oxathiolane ring is close to an envelope conformation, and both pyrimidine and carboxylate substituent are in the equatorial positions. The hexagonal packing is constructed by the hierarchical network of hydrogen bonds, which connect the molecules into chains, then into pairs of chains, and neighboring chains, oriented at the angle of 60°, make the final packing mode.
标题化合物C8H9N3O4S × 1/2(H2O)是药物拉米夫定中的一种杂质,在六方空间群P62中结晶,a = 10.208(1) 埃,c = 18.073(2) 埃。这种罕见的堆积是由氢键的分层网络构建的,氢键将分子连接成链,然后连接成对链,相邻的链以 60° 的角度定向,形成最终的堆积模式。该分子以带负电荷的羧基和带正电荷的氨基的齐聚物形式存在于晶体中。氧硫杂环接近于包络构象,嘧啶和羧酸取代基均位于赤道位置。六角形堆积是通过氢键的分层网络构建的,氢键将分子连接成链,然后连接成对链,相邻的链以 60° 的角度定向,形成最终的堆积模式。