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1-[4-(β-d-Allopyranosyloxy)benzylidene]semicarbazide hemihydrate  [cached]
Hua-Feng Chen,Xue Bai,Kuan Zhang,Ying Li
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536809055664
Abstract: The molecule of the title compound, C14H19N3O7·0.5H2O, exhibits an E conformation about the C=N double bond. The water molecule possesses crystallographically imposed twofold symmetry. In the crystal structure, the molecules are connected by intermolecular O—H...O and N—H...O hydrogen bonds into a three-dimensional network.
N-[4-(β-d-Allopyranosyloxy)benzylidene]methylamine  [cached]
Shi-Ming Lv,Lei Zheng,Hui Zhao,Ying Li
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809000944
Abstract: The title compound, C14H19NO6, was synthesized by the condensation reaction between hecilid (4-formylphenl-β-d-allopyranoside) and methylamine in methanol. In the crystal structure, the pyran ring adopts a chair conformation and adjacent molecules are linked by intermolecular O—H...O and O—H...N hydrogen bonds, forming a three-dimensional network.
1-[4-(2,3,4,6-Tetra-O-acetyl-β-d-allopyranosyloxy)benzylidene]thiosemicarbazide  [cached]
Li Fu,Xiu-juan Yin,Lei Zheng,Ying Li
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809007260
Abstract: The title compound, C22H27N3O10S, was synthesized by reaction of an ethanol solution of helicid (systematic name: 4-formylphenl-β-d-allopyranoside), thiosemicarbazide and acetic acid. The molecule exhibits a trans conformation with respect to the C=N double bond. The pyran ring adopts a chair conformation. In the crystal structure, the molecules are linked into chains parallel to the b axis by intermolecular N—H...O hydrogen bonds.
E-[4-(β-d-Allopyranosyloxy)phenyl]-1-(4-chlorophenyl)prop-2-enone ethanol solvate  [cached]
Cong-ling Yang,Hua-ling Luo,Xiu-juan Yin,Ying Li
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809006424
Abstract: The title compound, C21H21ClO7·C2H5OH was synthesized by the condensation reaction between helicid [systematic name: 4-(β-d-allopyranosyloxy)benzaldehyde] and 4-chloroacetophenone in ethanol. In the molecular structure, the pyranoside ring adopts a chair conformation. In the crystal structure, the molecules are linked by intermolecular O—H...O hydrogen bonds involving the OH groups from the pyranoside unit and from the ethanol solvent molecule.
(E)-4-(β-d-Allopyranosyloxy)cinnamyl 4-bromophenyl ketone ethanol solvate  [cached]
Xiu-Juan Yin,Xue Bai,Lei Zheng,Ying Li
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809029687
Abstract: The title compound, C21H21BrO7·C2H6O, was synthesized by the Claisen–Schimidt reaction of helicid (systematic name: 4-formylphenyl-β-d-allopyranoside) with 4-bromoacetophenone in ethanol. The pyran ring adopts a chair conformation. In the crystal structure, molecules are linked into a three-dimensional network by intermolecular O—H...O hydrogen bonds.
Tuberostemoamide hemihydrate
Rong-Rong Zhang,Zhi-Guo Ma,Guo-Qiang Li,Paul Pui-Hay But
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811043340
Abstract: In the crystal structure of the title compound {systematic name: (1′S,2R,2′R,3′S,6′R)-3′-ethyl-4-methyl-5H-5′-oxa-10′-azaspiro[furan-2,4′-tricyclo[,6]tridecane]-5,11′-dione hemihydrate}, C17H23NO4·0.5H2O, the asymmetric unit contains two molecules of tuberostemoamide with similar conformations and one water molecule. The tuberostemoamide molecule is composed of one seven-membered ring (A) and three five-membered rings (B, C and D). Ring A exists in a chair conformation, both rings B and C exist in envelope conformations, and ring D is almost planar with a mean deviation of 0.0143 (4) in one molecule and 0.0095 (3) in the other.. The dihedral angles between the planes of rings C and D are 75.1 (3)° in one molecule and 74.5 (3)° for the other. The solvent water molecule links the tuberostemoamide molecules through O—H...O(ketone) hydrogen bonds. Weak C—H...O interactions are also present, involving both the water molecule and a heterocyclic ether O-atom acceptor.
(1S)-1,2-O-Benzylidene-α-d-glucurono-6,3-lactone  [cached]
Sarah F. Jenkinson,Daniel Best,Alexander C. Weymouth-Wilson,Robert A. Clarkson
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809002876
Abstract: X-ray crystallographic analysis has established that the major product from the protection of d-glucoronolactone with benzaldehyde is (1S)-1,2-O-benzylidene-α-d-glucurono-6,3-lactone, C13H12O6, rather than the R epimer. The crystal structure exists as O—H...O hydrogen-bonded chains of molecules lying parallel to the a axis. The absolute configuration was determined by the use of d-glucuronolactone as the starting material.
Bharat Bhushan
International Journal of Pharmaceutical Research and Development , 2011,
Abstract: The phenyl (thio) semicarbazide derivatives of phthalimido pharmacophores were synthesized and evaluated for their anticonvulsant activity. A series of N4-(4-Methyl Phthalimido) Substituted Phenyl (Thio) Semicarbazide were synthesized by reaction of substituted phenyl (thio) semicarbazide with 4- methyl phthalic anhydride. All the synthesized compounds were characterized on the basis of their IR, 1HNMR and elemental analysis. The anticonvulsant activity of the titled compounds revealed that four compounds 6b (R=2-OCH3), 6d(R=4-CH3), 6e(R=4-OCH3), 6g (R=4-Cl) exhibited highly significant and comparable anticonvulsant activity with respect to standard drug Phenytoin.
Semicarbazide as potential source of formaldehyde and nitric oxide formation  [cached]
Nely Latyshko,Olga Gudkova,Mykola Dmytrenko
Drugs and Therapy Studies , 2012, DOI: 10.4081/dts.2012.e9
Abstract: Growing evidence that the potential carcinogen, semicarbazide, may get into the human body makes especially important of knowledge for its metabolic fate. While the general agreement that semicarbazide is aldehyde trapping agent and inhibitor of semicarbazide sensitive amine oxidase, which activity increases in blood and body tissues in pathological states, there is assumption that at least one clearans mechanism must operate in vivo. We supposed that semicarbazide may be metabolysed by the members of cytochrome P-450 (CYP-450) family in liver microsomes generating dangerous products. Using difference spectrometry we have found that semicarbazide-induced spectral changes reflect its binding to the active site of CYP-450. To identify the products of semicarbazide decomposition, 7.5 mM semicarbazide was incubated with rat liver microsomes. The concentrations of formaldehyde, nitric oxide on the basis of accumulation of nitrite in the medium, and ammonium were determined by microplate-based spectrophotometry and fluorometry, accordingly. There was net increase in the concentrations of the products during incubation in comparison with control to the extent of 22.04±7.1 for formaldehyde and 11.29±1.91 for nitric oxide μmol/mg protein within 15 min. Formaldehyde and nitric oxide formations were additionally confirmed by using their traps. Dimedone, formaldehyde trap, decreased its amount in the reaction mixture by 55%, whereas iron-dithiocarbamate complex, nitric oxide trap, by 52%. The results suggest that semicarbazide transformation is viewed as two important pathways: one, yielding formaldehyde, and other, producing nitric oxide and ammonium. These hazard products are the reasons for semicarbazide toxicity.
Sarah F. Jenkinson,Sebastian D. Rule,Kathrine V. Booth,George W. J. Fleet
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536807059739
Abstract: X-ray crystallography unequivocally showed that protection of the free hydroxyl group of 3,5-O-benzylidene-d-lyxono-1,4-lactone with diphenyldiazomethane proceeded with retention of configuration to give the title compound, C25H22O5. The crystal structure consists of layers of interlocked molecules lying parallel to the a axis.
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