5-hydroxy-5,5'-bibarbituric acid | 32016-07-2

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 二嗪类
• 英文名称: 5-hydroxy-5,5'-bibarbituric acid
• 英文别名: 5-hydroxyhydurilic acid；5-hydroxy-[5,5']bipyrimidinyl-2,4,6,2',4',6'-hexaone；5-Hydroxy-5-(2,4,6-trioxo-1,3-diazinan-5-yl)-1,3-diazinane-2,4,6-trione
• CAS: 32016-07-2
• 化学式: C₈H₆N₄O₇
• 分子量: 270.158
• InChiKey: QARYKXPNVLLLDE-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -3.93
• 重原子数：
  19.0
• 可旋转键数：
  1.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.25
• 拓扑面积：
  170.77
• 氢给体数：
  5.0
• 氢受体数：
  7.0

反应信息

• 作为产物：
  描述：

  巴比妥酸 在 1,8-双二甲氨基萘 作用下， 以 甲醇 为溶剂， 生成 5-hydroxy-5,5'-bibarbituric acid
  参考文献：
  名称：

  Polymorphism in an unexpected caesium complex of 5-hydroxyhydurilic acid

  摘要：

  Vigorous reaction of barbituric acid with caesium hydroxide in water resulted in an unexpected coupling product, 5-hydroxyhydurilic acid, complexed to caesium, giving poly[[caesium-mu(5)-5-hydroxyhydurilato] hemihydrate], {[Cs(C8H5N4O7)]center dot 0.5H(2)O}(n). This was obtained in two different polymorphic forms, depending on the method of crystal growth. Slow solvent evaporation yielded an orthorhombic polymorph, (I), which crystallized in the space group Pnab (non-standard setting of Pbcn), with the uncoordinated water molecule lying on a crystallographic twofold axis. The water molecule is sandwiched into cavities within the structure and is securely held in place by N-H center dot center dot center dot O and O-H center dot center dot center dot O hydrogen bonding. Polymorph (II) is monoclinic, although the unit-cell parameters are similar to those of polymorph (I), and it crystallizes in the space group C2/c, with the uncoordinated water molecule again lying on the twofold axis and secured by hydrogen bonding. The differences between the two polymorphs, both of which have nine-coordinate caesium and a similar first-shell environment of all structural components, are in the overall arrangement of the cations, anions and water molecules, and in the shape of the cavities, revealed by inspecting and comparing crystal-packing diagrams.

  DOI：

  10.1107/s0108270105029318