• Bulletin of the Korean Chemical Society
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• v.11 no.1
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• pp.19-21
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• 1990

The crystal structure of Bithionol, $C_{12}H_6Cl_4O_2S$, has been determined from X-ray intensity data measured by Enraf-Nonius CAD-4 diffractometer using graphite-monochromatized $Mo-K\alpha$ radiation. The crystal data as follows; triclinic space group P{\bar{1}}$, a = 8.879(2), b = 10.782(1), c = 8.511(1)${\AA}$, ${\alpha}$ = 115.43(1), ${\beta}$ = 115.22(1), ${\gamma}\;=\;74.44^{\circ}(1)$. ${\mu}\;=\;9.51\;cm^{-1}$, F(000) = 356, Z = 2. Final R value is 0.036 for independent 2669 observed reflections. Each six-membered benzene rings are coplanar within experimesntal errors and the dihedral angle between these planes is $81.28^{\circ}$ (1). The S-(1) and S-C(7) distances are 1.787(2) and 1.791(3)${\AA}$, respectively.

• Polymer(Korea)
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• v.35 no.6
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• pp.605-609
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• 2011

Composite nanofibers were prepared by electrospinning and thermal treatment from poly (vinylidene fluoride) (PVDF)-$SiO_2$ blend solution. The nanofibers were stacked on layers to produce fully interconnected pores. TEM micrographs and EDX spectra confirmed the presence of $SiO_2$ in the composite nanofibers. The porosity of nanofibers was effectively enhanced by the introduction of electrospinning technique. ATR-FTIR and XRD results revealed that PVDF in the composite nanofibers exhibited the mixture crystal structure of ${\alpha}$-phase and ${\beta}$-phase. The crystal structure of ${\alpha}$-phase and crystallinity increased by the thermal treatment. In addition, the mechanical properties, thermal stability and hydrophobicity were markedly amplified by the thermal treatment.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.2
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• pp.94-98
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• 2017

In the past few years, Sn-3.0Ag-0.5Cu (weight%) solder composition has been a representative material to electronic industries as a replacement of Pb-base solder alloy. Therefore, extensive studies on process and/or reliability related with the composition have been reported. However, recent rapid rise in Ag price has demanded solder compositions of low Ag content. In this study, Sn-3.0Ag-0.5Cu solder bar sample was fabricated by melting of Sn, Ag and Cu metal powders. Crystal structure and element concentration were analyzed by XRD, optical microscope, FE-SEM and EDS. The Sn-3.0Ag-0.5Cu solder sample was composed of ${\beta}$-Sn, ${\varepsilon}-Ag_3Sn$ and ${\eta}-Cu_6Sn_5$ phases.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3317-3320
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• 2012

A novel energetic compound, bifurazano[3,4-b:3',4'-f]furoxano[3'',4''-d] oxacyclohetpatriene (BFFO), was synthesized through special etherification and its structure was determined by single crystal X-ray diffraction. The crystal of $BFFO{\cdot}H_2O$ is monoclinic, space group P2(1)/c with crystal parameters of a = $9.324(4){\AA}$, b = $9.727(4){\AA}$, c = $10.391(4){\AA}$, ${\beta}=106.305(6)^{\circ}$, V = $904.5(6){\AA}^3$, Z = 4, ${\mu}=0.17mm^{-1}$, F(000) = 512 and $D_c=1.866g\;cm^{-3}$. Spectroscopic properties and thermal behaviors of BFFO were studied. BFFO presents good detonation properties.

• Journal of Integrative Natural Science
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• v.8 no.1
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• pp.30-39
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• 2015

The crystal structure of the potential active 2-amino-4-(4-hydroxy-3-methoxyphenyl)-7, 9-dimethyl-5-oxo-4, 5, 6, 7-tetrahydropyrano [2, 3-d] pyrazolo [3, 4-b] pyridine-3-carbonitrile ($C_{21}H_{22}N_5O_6S$) has been determined from single crystal X-ray diffraction data. In the title compound crystallizes in the monoclinic space group P-1 with unit cell dimension a=8.1201(9)${\AA}$, b=12.2684(4)${\AA}$ and c=12.387(2)${\AA}$ [${\alpha}=69.573^{\circ}$, ${\beta}=12.168^{\circ}$ and ${\gamma}=76.060^{\circ}$]. In the structure the pyrazole, pyridine and pyran are almost coplanar each other. The crystal packing is stabilized by intermolecular C-H...O and N-H... O hydrogen bond interaction.

• Journal of Integrative Natural Science
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• v.8 no.1
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• pp.19-29
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• 2015

In view of the growing medicinal importance of chromene and its derivatives, the single crystal X-ray diffraction study was carried out for the potential active 4,6-dimethyl-9-phenyl-8,12-dioxa-4,6-diazatetracyclo [8.8.0.02,7.013,18]octadeca-2(7),13,15,17-tetraene-3,5,11-trione-2-ethoxyphenyl (2E)-but-2-enoate ($C_{18}H_{20}N_2O_5$). In the title compound are two molecules exist in the asymmetric unit. It crystallizes in the monoclinic space group $P2_1/c$ with unit cell dimension a=14.608(3) ${\AA}$, b=12.845(3) and c= 17.781(4) [alpha & gamma=$90^{\circ}$ beta=$91.233(5)^{\circ}$]. Both pyran and pyran ring of the chromene moiety adopts sofa conformation in the molecule A & B. The crystal structure is stabilized by intramolecular C-H...O hydrogen bond interaction.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2627-2632
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• 2010

Hormone sensitive lipase (HSL) plays a major role in energy homeostasis and lipid metabolism. Several crystal structures of HSL-homolog proteins have been identified, which has led to a better understanding of its molecular function. HSL-homolog proteins exit as both monomer and dimer, but the biochemical and structural basis for such oligomeric states has not been successfully elucidated. Therefore, we determined the crystal structure of HSL-homolog protein EstE7 from a metagenome library at $2.2\;{\AA}$ resolution and characterized the oligomeric states of EstE7 both structurally and biochemically. EstE7 protein prefers the dimeric state in solution, which is supported by its higher enzymatic activity in the dimeric state. In the crystal form, EstE7 protein shows two-types of dimeric interface. Specifically, dimerization via the external ${beta}8$-strand occurred through tight association between two pseudosymmetric folds via salt bridges, hydrogen bonds and van der Waals interactions. This dimer formation was similar to that of other HSL-homolog protein structures such as AFEST, BEFA, and EstE1. We anticipate that our results will provide insight into the oligomeric state of HSL-homolog proteins.

• Archives of Pharmacal Research
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• v.15 no.1
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• pp.52-57
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• 1992

The molecular structure of a natural compound was determined by single crystal X-ray diffraction analysis. The compound was isolated by methanol extraction and repeated chromatography from the stem of Paulownia tomentosa. Yellow prismatic crystals of the compound, which were recrystallized from tetrahydrofuran, are triclinic, with a = 7.310 (6), b = 10.753(6), c = 11.586(5) ${\AA}.\;\alpha= 93.30(6),\;\beta=105.62(10),\;\gamma=109.49(7)^\circ,\;D_x=1.514,\;D_m=1.51 g/cm^3$, space group P1 and Z = 2. The structure was solved by direct method, and refined by least-squares procedure to the final R-value of 0.032 for 1271 independent reflections $(F\le3\sigma{(F))}$. The compound is one of new furanquinone analogue. The molecule has a nearly planar conformation with an intramolecular hydrogen bond. In the crystal, the planar molecules are arranged as a prallel sheet-like pattern, and these stackings are stabilized by the O-H...O type intermolecular hydrogen bonds. The other intermolecular contacts appear to be the normal van der Waals interactions.

• Archives of Pharmacal Research
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• v.25 no.3
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• pp.275-279
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• 2002

The crystal structure of byakangelicin, one of furanocoumarin aldose reductase inhibitors, was determined by X-ray diffraction method. The crystal is triclinic, with a=8.114(1), b=10.194(1), $c=11.428(1)\AA,{\;}{\alpha}=111.50(1),{\}{\beta}=95.57(1),{\}{\gamma}=112.52(1)^{circ},{\;}D_x=1.41,{\;}D_m=1.39{\;}g/cm^3$, space group P1 and Z=2. The intensity data were collected by ${\omega}-2{\theta}$ scan method with $CuK_{a}$ radiations. The structure was solved by direct method and refined by full matrix least-squares procedure to the final R-value of 0.056. There are two molecules with different conformations in an asymmetric unit. The molecules are kept by two intermolecular O-HO type hydrogen bonds and van der Waal's forces in the crystal. The absolute configuration of the molecules was estimated to S-form by the 'Eta refinement' procedure.

• Advances in Traditional Medicine
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• v.9 no.2
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• pp.164-173
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• 2009

The anti-inflammatory effect of Spirulina fusiformis on monosodium urate crystal-induced inflammation in mice has been investigated and compared with the non-steroidal anti-inflammatory drug Indomethacin. The paw volume, lysosomal enzyme activities, lipid peroxidation, anti-oxidant status and inflammatory mediator tumour necrosis factor-$\alpha$ were studied in control and monosodium urate crystal-induced mice after oral administration of Spirulina platensis in an experimental model for gouty arthritis. In the induced mice, the levels of lysosomal enzymes, inflammatory mediator tumour necrosis factor-$\alpha$, lipid peroxidation and the paw volume increased significantly, whereas the antioxidant status decreased when compared to control mice. $\beta$-glucuronidase and lactate dehydrogenase level were also found to be increased in untreated monosodium urate crystal-incubated polymorphonuclear leucocytes. After the oral administration of Spirulina fusiformis, the physical and biochemical changes observed in monosodium urate crystal-induced animals were significantly restored to near normal levels. The results clearly indicated the anti-inflammatory role of Spirulina fusiformis, a promising drug for gouty arthritis.