A monoclinic polymorph of theophylline
نویسندگان
چکیده
A monoclinic polymorph of theophylline, C(7)H(8)N(4)O(2), has been obtained from a chloro-form/methanol mixture by evaporation under ambient conditions. The new polymorph crystallizes with two mol-ecules in the asymmetric unit. The structure features inter-molecular N-H⋯O hydrogen bonds, resulting in the formation of dimers between two crystallographically different mol-ecules; each mol-ecule acts as both donor and acceptor.
منابع مشابه
Polymorphs of anhydrous theophylline: stable form IV consists of dimer pairs and metastable form I consists of hydrogen-bonded chains.
The structure of a previously unreported polymorph of anhydrous theophylline (1,3-dimethyl-3,7-dihydro-1H-purine-2,6-dione), C(7)H(8)N(4)O(2), has been determined at 100 K and shown to have monoclinic symmetry with Z' = 2. The structure is named form IV and experimental observation indicates that this is the stable form of the material. The molecular packing consists of discrete hydrogen-bonded...
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عنوان ژورنال:
دوره 67 شماره
صفحات -
تاریخ انتشار 2011