ABSTRACT
As the title gabapentin complex, [Zn(4)(OH)(2)(NO(3))(2)(C(9)H(17)NO(2))(4)(H(2)O)(4)](NO(3))(4) is located about a centre of inversion, the asymmetric unit contains two disordered nitrate ions and half a complex mol-ecule. The two zinc ions have different coordination environments: one is slightly distorted octa-hedral and the other is trigonal-pyramidal. The conformation of the gabapentin mol-ecule is defined by the formation of two intra-molecular O-Hâ¯O hydrogen bonds. Furthermore, the ammonium H atoms are involved in numerous hydrogen bonds with the disordered nitrate anions.
ABSTRACT
In the title compound, C(10)H(18)N(+)·C(2)H(3)O(2) (-), the ammonium H atoms of the cation are linked to three acetate anions via N-Hâ¯O hydrogen bonds, forming a chain structure extending along the b axis.
ABSTRACT
The title compound, C(9)H(18)NO(2) (+)·NO(3) (-), is an anhydrous nitrate salt of gabapentin, which is formed serendipitously in the presence of selected non-coordinating metals. The crystal structure involves extensive hydrogen bonding between the -NH(3) (+) and -COOH groups and the nitrate anion.
ABSTRACT
The structures of the inclusion complexes formed by heptakis(2,6-di-O-methyl)cyclomaltoheptaose and methyl-, ethyl-, propyl- and butyl parabens have been solved and analysed by X-ray diffraction. Each inclusion complex crystallises in the space group P2(1)2(1)2(1) with Z=4 and a host-to-guest ratio of 1:1. However the packing arrangements and modes of guest inclusion are not equivalent for the four structures. The analytical data indicated that two isostructural pairs, the methyl- and ethyl-paraben complexes, have similar cell parameters that differ from those of the propyl- and butyl paraben complexes. The results of thermogravimetric analysis and differential scanning calorimetry of the complexes are also reported.
Subject(s)
Cyclodextrins/chemistry , Models, Molecular , Parabens/chemistry , Carbohydrate Conformation , Hydrophobic and Hydrophilic Interactions , Thermodynamics , Water/chemistry , X-Ray DiffractionABSTRACT
The isolation and structural elucidation by single crystal X-ray diffraction of triclinic and monoclinic modifications of an inclusion complex of beta-cyclodextrin with the same guest, methylparaben, are reported.
