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Eight 7-benzyl-3-tert-butyl-1-phenylpyrazolo[3,4-d]oxazines, encompassing structures containing no intermolecular hydrogen bonds, and hydrogen-bonded structures in one, two or three dimensions.

ABSTRACT: 7-Benzyl-3-tert-butyl-1-phenyl-6,7-dihydro-1H,4H-pyrazolo[3,4-d][1,3]oxazine, C22H25N3O, (I), and 3-tert-butyl-7-(4-methylbenzyl)-1-phenyl-6,7-dihydro-1H,4H-pyrazolo[3,4-d][1,3]oxazine, C23H27N3O, (II), are isomorphous in the space group P2(1), and molecules are linked into chains by C-H...O hydrogen bonds. In each of 3-tert-butyl-7-(4-methoxybenzyl)-1-phenyl-6,7-dihydro-1H,4H-pyrazolo[3,4-d][1,3]oxazine, C23H27N3O2, (III), which has cell dimensions rather similar to those of (I) and (II), also in P2(1), and 3-tert-butyl-1-phenyl-7-[4-(trifluoromethyl)benzyl]-6,7-dihydro-1H,4H-pyrazolo[3,4-d][1,3]oxazine, C23H24F3N3O, (IV), there are no direction-specific interactions between the molecules. In 3-tert-butyl-7-(4-nitrobenzyl)-1-phenyl-6,7-dihydro-1H,4H-pyrazolo[3,4-d][1,3]oxazine, C22H24N4O3, (V), a combination of C-H...O and C-H...N hydrogen bonds links the molecules into complex sheets. There are no direction-specific interactions between the molecules of 3-tert-butyl-7-(2,3-dimethoxybenzyl)-1-phenyl-6,7-dihydro-1H,4H-pyrazolo[3,4-d][1,3]oxazine, C24H29N3O3, (VI), but a three-dimensional framework is formed in 3-tert-butyl-7-(3,4-methylenedioxybenzyl)-1-phenyl-6,7-dihydro-1H,4H-pyrazolo[3,4-d][1,3]oxazine, C23H25N3O3, (VII), by a combination of C-H...O, C-H...N and C-H...pi(arene) hydrogen bonds, while a combination of C-H...O and C-H...pi(arene) hydrogen bonds links the molecules of 3-tert-butyl-1-phenyl-7-(3,4,5-trimethoxybenzyl)-6,7-dihydro-1H,4H-pyrazolo[3,4-d][1,3]oxazine, C25H31N3O4, (VIII), into complex sheets. In each compound, the oxazine ring adopts a half-chair conformation, while the orientations of the pendent phenyl and tert-butyl substituents relative to the pyrazolo[3,4-d]oxazine unit are all very similar.

SUBMITTER: Castillo JC

PROVIDER: S-EPMC2720151 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Eight 7-benzyl-3-tert-butyl-1-phenylpyrazolo[3,4-d]oxazines, encompassing structures containing no intermolecular hydrogen bonds, and hydrogen-bonded structures in one, two or three dimensions.

Castillo Juan C JC Abonía Rodrigo R Cobo Justo J Glidewell Christopher C

Acta crystallographica. Section C, Crystal structure communications 20090730 Pt 8

7-Benzyl-3-tert-butyl-1-phenyl-6,7-dihydro-1H,4H-pyrazolo[3,4-d][1,3]oxazine, C22H25N3O, (I), and 3-tert-butyl-7-(4-methylbenzyl)-1-phenyl-6,7-dihydro-1H,4H-pyrazolo[3,4-d][1,3]oxazine, C23H27N3O, (II), are isomorphous in the space group P2(1), and molecules are linked into chains by C-H...O hydrogen bonds. In each of 3-tert-butyl-7-(4-methoxybenzyl)-1-phenyl-6,7-dihydro-1H,4H-pyrazolo[3,4-d][1,3]oxazine, C23H27N3O2, (III), which has cell dimensions rather similar to those of (I) and (II), also ...[more]

PMID: 19652329

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Dataset Information

Eight 7-benzyl-3-tert-butyl-1-phenylpyrazolo[3,4-d]oxazines, encompassing structures containing no intermolecular hydrogen bonds, and hydrogen-bonded structures in one, two or three dimensions.

Publications

Eight 7-benzyl-3-tert-butyl-1-phenylpyrazolo[3,4-d]oxazines, encompassing structures containing no intermolecular hydrogen bonds, and hydrogen-bonded structures in one, two or three dimensions.

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