• Korean Journal of Crystallography
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• v.6 no.1
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• pp.43-48
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• 1995

The crystal structure of P-toluenesulfonanilide, C13H13NO2S is monoclinic, space group P21/c, a=8.777(1)Å, b=9.784(2)Å, c=15.139(2)Å, β=99.00(1)°, Z=4, V=1284.0(6)Å3, Dc=1.28g/cm33, λ(Mo-Kα)=0.71069Å, μ=2.3cm-1, F(000)=520, Temperature : 293±3K, R=0.038 for 711 Fo<3.0σ unique observed reflection. The structure was determuned by direct method and refined by full-matrix least squares refinement. Two benzene rings have the dihedral angle of 68.4°. Moleculs are accumulated according to the c axis with two fold screw and contacted by van der Walls force.

• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.81-84
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• 2008

In the present study, we report 1H and 13C NMR data of 19 methoxyflavonol derivatives with different substitution patterns on A- and B-ring. In addition, the influence of the methoxy substituents in A- and B-ring on the 1H and 13C NMR chemical shifts is discussed: the 1H and 13C chemical shifts of and the number of methoxyl groups provided information allowing elimination of many structural isomers from consideration and in certain instances greatly simplified structural elucidation.

• Korean Journal of Crystallography
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• v.12 no.3
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• pp.141-144
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• 2001

From the reaction of Na[Ga(N₃)₄] with PPh₃, an ionic compound [Ph₃P(OH)]/sup +/[N₃]/sup -/ (1) was isolated. Compound 1 was characterized by spectroscopy (¹H-NMR, /sup 13C{¹H}-NMR, and IR) and X-ray diffraction. Crystallographic data for 1 : orthorhombic space group P2₁2₁2₁, a = 10.491 (4) Å, b=11.603(5)Å, c=13.149(5)Å, Z=4, R(wR₂)=0.0547(0.0978).

• Journal of the Korean Chemical Society
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• v.39 no.7
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• pp.559-563
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• 1995

The three metabolites, Germacrene alcohol(1), Aaptamine(2) and Hexacyclic terpene(3) were isolated from Marine Sponge Luffariella sp., collected in October 1992, Manado Bay, Sulawesi in Indonesia showed in vitro activity against KB cancer cell line, and structure assignment for 1 was corrected by comparison of their spectral data with the literature $values^1$. Their structure were elucidated by $^1H$, $^13C$ NMR, $^1H$ $^13C$(1 bond) Heteronuclear Multiple Quantum Coherence Spectroscopy$(HMQC)^2$, $^1H$ $^13C$(2 and 3 bond) Heteronuclear Multiple Bond Correlation Spectroscopy$(HMBC)^3$, Electron Impact Mass Spectroscopy(EI ms), Ultra-violet Spectroscopy(UV) and Infrared Spectroscopy(IR).

• The Journal of Natural Sciences
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• v.16 no.1
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• pp.15-29
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• 2005

To produce a thermostable cyclodextrin by using thermotolerant cyclomaltodextrin glucanotransferase(CGTase), a thermophilic and alkalophilic bacterium isolate, designated B-13 showing the highest CGTase activity was isalated from natural sources and identified as Bacillus cereus B-13 based on the morphological and physiological characteristics, and 16S rRNA sequence. The maximal CGTase activity (130 U/ml) was obtained when Bacillus cereus B-13 was cultured in SYC medium containing 2.0% soluble starch, 1.0% yeast extracts, 1% corn steep liquor and 1% $Na_2CO_3$ (pH 8.5) at $50^{\circ}C$ for 24 h and about 80% of maximal activity was also showed in he culture broth of $60^{\circ}C$ for 18 h. Optimum reaction temperature and pH of the partial purified CGTase for soluble starch were $65^{\circ}C$ and pH 8.5-9.0 respectively. The partial purified CGTase were also stable below $80^{\circ}C$ and pH 5.0-10.0. When 1% soluble starch was digested with the partial purified CGTase, the yield of cyclodextrin was 49%.

• Korean Journal of Crystallography
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• v.4 no.1
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• pp.6-10
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• 1993

11 β ,17 β -dihydroxy-9a-fluoro-l7a-methyl androst-4-en-3-one (Fluoxymesterone), CgoH29 FO,, orthorhombic, P2,2,2,, a=13.468(5) A, b= 19.554 (2)A, c=6.578(9)A, a=b=r=90˚, A (CuKa)=1.5406 A , Dm=1.289cm-3, Dc=1.299cm-3 and Z=4 at T=298k. The structure was solved by direct method using seminvariants of ggg Parity group and refined by the full-matrix least-square method, resulting model with reliability factor R=0.069 for 1098 unique reflection over 3σ . Ring A is an 1β-2a-half chair, 5 ring has a highly symmetrical chair conformation, C ring is in a distorted chair conformation and D ring is a 13aenveLope conformation. In the crystal structure, the molecules are packed with a hydrogen bond of 011-H23‥‥03(0.5+x, 1.5-y, 1.0-z) [1.94(9) A of H‥‥0.2.786(9)A of 0‥‥0 and 165(8) ˚ of

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2535-2541
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• 2009

Prebiotic isomaltooligosaccharide preparations contain $\alpha$-D-glucooligosaccharides comprising isomaltooligosaccharides (IMOs) and non-prebiotic maltooligosaccharides (MOs). They are both glucose oligosaccharides characterized by their degree of polymerization (DP) value (from 2 to $\sim$10), linkages types and positions (IMOs: $\alpha$-(1$\rightarrow$2, 3, 6 and in a lower proportion internal 1$\rightarrow$4) linkages, MOs: α-(1$\rightarrow$4) linkages). Their structure is the key factor for their prebiotic potential. In order to determine and elucidate the exact structure of unknown IMOs and MOs, unambiguous assignments of $^{13}C$ and $^1H$ chemical shifts of commercial standards, representative of IMOs and MOs diversity, have been determined using optimized standard one and two-dimensional experiments such as $^1H$ NMR, $^{13}C$ NMR, APT and ${^1}H-{^1}H$ COSY, TOCSY, NOESY and <$^1H-{^{13}}C$ heteronuclear HSQC, HSQC-TOCSY, and HMBC. Here we point out the differential effect of substitution by a glucose residue at different positions on chemical shifts of anomeric as well as ring carbons together with the effect of the reducing end configuration for low DP oligosaccharides and diasteroisotopic effect for H-6 protons. From this study, structural $^{13}C$ specific spectral features can be identified as tools for structural analysis of isomaltooligosaccharides.

• Bulletin of the Korean Chemical Society
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• v.13 no.5
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• pp.565-570
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• 1992

The 1,5-sigmatropic rearrangements involving group (X) migration in ${\omega}$(X)-substituted 1,3-pentadiene, $C^1H_2=C^2H-C^3H=C^4H-C^5H_2-X$, where X = H, $CH_3$, $BH_2$, $NH_2$, OH or F, are investigated MO theoretically using the AM1 method. For the migrating groups without lone pair electrons, X = H, $CH_3$, or $BH_2$, the suprafacial pathway is favored, whereas for the migrating groups with lone pair electrons participating in the TS, $X=NH_2$, OH, or F, the antarafacial pathway is favored electronically. However excessive steric inhibition in the antarafacial TS for $X=NH_2$ leads to subjacent orbital controlled suprafacial process. The antarafacial shift of F is relatively disfavored compared to that of OH due to smaller orbital overlap and larger interfrontier energy gap in the TS.

• Journal of Mushroom
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• v.13 no.1
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• pp.68-73
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• 2015

Hypocrea disease is the most severe disease of oyster mushroom cultivation in Korea. Physiological and ecological studies were performed on the pathogens (Hypocrea spp.) to obtain basic information for developing the integrated disease management system. Fourteen isolates of Hypocrea were collected from oyster mushroom house in five areas. Pathogenic fungi causing disease of oyster mushroom were identified as Hypocrea sp. based on morphological characteristics and pathogenicity. Two isolates (H-1, H-12) showed the fastest growth at $15^{\circ}C$ but four isolates (H-8, H-9, H-13, H-14) showed slower growth than those of other isolates at $20^{\circ}C$ and $25^{\circ}C$. Stroma with ascocarps and ascospore were produced on PDA under fluorescent light. The five isolates produced stroma with ascocarps and ascospores. Formation of fruiting body of strains H-14 of Hypocrea were the best out of all the strains on the potato dextrose agar (PDA). Also, fruiting bodies and ascospores were completely produced under fluorescent light. The growth of the isolates was correlated with total carbon content. The stroma of the isolates was formed mainly in histidine and asparagine treatment and especially in histidine-70 and asparagine-100 treatment. In the test of pathogenicity, after and before spawning showed very fast incidence of disease.

• Journal of the Korean Magnetic Resonance Society
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• v.19 no.1
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• pp.18-22
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• 2015

The structural geometry of $[N(CH_3)_4]_2CdCl_4$ in a hexagonal phase is studied by $^1H$ MAS NMR, $^{13}C$ CP/MAS NMR, and $^{14}N$ NMR. The changes in the chemical shifts for $^{13}C$ and $^{14}N$ in the hexagonal phase are explained by the structural geometry. In addition, the temperature dependencies of the spin-lattice relaxation time in the rotating frame $T_{1{\rho}}$ for $^1H$ MAS NMR and $^{13}C$ CP/MAS NMR are measured.