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A monoclinic polymorph of theophylline.

ABSTRACT: 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.

SUBMITTER: Zhang S

PROVIDER: S-EPMC3239002 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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A monoclinic polymorph of theophylline.

Zhang Shuo S Fischer Andreas A

Acta crystallographica. Section E, Structure reports online 20111119 Pt 12

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. ...[more]

PMID: 22199851

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