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Redetermined structure of oxaline: absolute configuration using Cu K? radiation.

ABSTRACT: In the title compound, C(24)H(25)N(5)O(4), the stereogenic C atom bonded to three N atoms and one C atom has an S configuration and its directly bonded neighbour has an R configuration. An intra-molecular N-H?O hydrogen bond supports the near coplanarity of the two C(3)N(2)-five-membered rings [dihedral angle = 5.64?(10)°]. In the crystal, mol-ecules are linked by N-H?N hydrogen bonds, forming a C(8) chain propagating in [001]. The chains are connected by C-H?O inter-actions, generating a three-dimensional network. The previous study [Nagel et al. (1974 ?). Chem. Commun. pp. 1021-1022] did not establish the absolute structure and no atomic coordinates were published or deposited.

SUBMITTER: Qu P

PROVIDER: S-EPMC3379231 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature

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Redetermined structure of oxaline: absolute configuration using Cu Kα radiation.

Qu Peng P Wu Zhi-Yong ZY Zhu Wei-Ming WM

Acta crystallographica. Section E, Structure reports online 20120505 Pt 6

In the title compound, C(24)H(25)N(5)O(4), the stereogenic C atom bonded to three N atoms and one C atom has an S configuration and its directly bonded neighbour has an R configuration. An intra-molecular N-H⋯O hydrogen bond supports the near coplanarity of the two C(3)N(2)-five-membered rings [dihedral angle = 5.64 (10)°]. In the crystal, mol-ecules are linked by N-H⋯N hydrogen bonds, forming a C(8) chain propagating in [001]. The chains are connected by C-H⋯O inter-actions, generating a three- ...[more]

PMID: 22719429

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