• Journal of the Korean Chemical Society
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• v.37 no.5
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• pp.473-476
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• 1993

Dipropargyldiphenylmetane, $C_{19}H_{16}, crystallizes in a monoclinic space group $C2/_c$$ with a = 11304(3), b = 20.799(5), c = 6.622(2)${\AA}$, ${\beta} = 112.8(3)^{\circ}$, Z = 4, V = 1435.3${\AA}^3,\;F(000)\;=\;520,\;D_c\;=\;1.14g{\cdot}cm^{-3}$ and ${\mu}\;=\;0.32\;cm^{-1}$. The structure was solved by direct methods and all non-H atoms were identified in the E-map. The final refinement gave R = 0.055 from 1328 unique observed reflections with I $\geq$ -1.0 $\sigma(I).$ The molecule belongs to the point group $C_2$ of Symmetry by possessing the 2-fold axis which coincides witeh the crystallographic symmetry axis in the unit cell. The linear propargyl moiety is nearly $perpendicular(94.2)^{\circ}$ to the molecular plane of the benzene ring. The internal angle of methane carbon atoms in $108.1(1)^{\circ}$, bonding to the benzene and the propargyl moiety with the bond lengths of 1.530(2) and $1.560(2)\AA$, respectively. The shortest contant between the molecules is $3.538(2)\AA$ between C(9) and C(9) (-x, y, -1/2-z).

• Journal of the Mineralogical Society of Korea
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• v.6 no.2
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• pp.116-121
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• 1993

A single crystla of zeolite $Na_{78}Rb_{28}-X$ (approximate composition) was prepared by exposing $Na_{92}-X$ at $350^{\circ}C$ to 0.1 Torr of rubidium vapor, and its structure was determined by single-crystal x-ray diffraction methods in the cubic space group, Fd3, ${\alpha}=25.045(4){\AA}$. The structure was refined to the final error indices $R_1=0.082$ and $R_2=0.084$ with 353 for which I>$3{\sigma}(I)$. Only about 28 of the 92 $Na^+$ ions per unit cell were reduced and only about 14 of the 28 $Na^0$ atoms produced were retained within the zeolite. A $Na_5{^{4+}}$ cluster is present within each sodalite cavity. It is a centered tetrahedron (like $CH_4$) with bond $length=2.80(2){\AA}$ and angle tetrahedral by symmetry, and shows the full symmetry of its site. $T_d$, at the center of the sodalite cavity. Each of the four terminal atoms of the $Na_5{^{4+}}$ cluster bond to three framework oxygens at $2.36(2){\AA}$. At the centers of some double 6-rings are sodium atoms which bridge linearly between $Na_5{^{4+}}$ clusters to form agglomerations such as short zig-zag chains $Na_5{^{4+}}$ clusters. Delocalized electrons, located primarily on the sodiums at centers of the sodalite and (likely) double-six-ring cavities, contribute to the stability of the clusters.

• Journal of the Korean Chemical Society
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• v.35 no.6
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• pp.630-635
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• 1991

The crystal structure of a bromine sorption complex of dehydrated fully $Ca^{2+}$-exchanged zeolite A (a = 12.211(2) ${\AA}$) has been determined by single-crystal X-ray diffraction techniques in the cubic space group, Pm3m at $21(1)^{\circ}C$. The crystal was prepared by dehydration at $360^{\circ}C$ and 2 ${\times}$ $10^{-6}$ Torr for 2 days, followed by exposure to about 180 Torr of bromine vapor at $24^{\circ}C$ for 30 min. In the resulting structure, six $Ca^{2+}$ ions are located on two different threefold axes associated with 6-ring oxygens. A total of six dibromine molecules are sorbed per unit cell. Each $Br_2$ molecule approaches a framework oxide ion axially, with O-Br = 3.12(7) ${\AA}$, Br-Br = 2.64(9) ${\AA}$ and O-Br-Br = $178(2)^{\circ}$, indicating a charge-transfer interaction. Full-matrix least-squares refinement converged to a conventional R index of 0.104 using the 103 independent reflections for which I > 3${\sigma}$ (I).

• Korean Journal of Crystallography
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• v.8 no.2
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• pp.127-131
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• 1997

The crystal structure of a bromine sorption complex of vacuum-dehydrated Ag+ and Ca2+ exchanged zeolite A(a=12,234(1) Å) has been determined by single-crystal X-ray diffraction methods in the cubic space group Pm3m. The crystal was prepared by flow method using exchange solution in which mole ratio of AgNo3 and Ca(NO3)2 was 1:150 with a total concentration of 0.05M. The crystal was dehydrated at 360℃ and 2 ×10-6 Torr for 2days, followed by exposure to 180 Torr of Br2 vapor for 20min. full-matrix least-squares refinements converged to the final error indices of R1=0.111 and R2=0.101 using 90 reflections for which I>3o(I). About 3.1 Ag+ ions and 4.45 Ca2+ ions lie on the two crystallographically nonequivalent three-fold axes associated with 6-ring oxygens. A total of six bromine molecules are sorbed per unit cell. Each bromine molecule approaches a framework oxide ions axially (Br-Br-O=171(2)', O-Br=3.25(6) Å; and Br-Br=2,61(8) Å by a charge-transfer interaction.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.279-286
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• 2005

The herbicidal activities against pre-emergence barnyard grass (Echinochloa crus-galli) by a series of new 2-(4-(6-chloro-2-benzoxazolyloxy)phenoxy)-N-phenylpopionamide derivatives as substrate molecule were studied using molecular holographic (H) quantitative structure activity relationships (HQSAR) methodology. From the based on the findings, the higher herbicidal active compounds are predicted by the derived HQSAR model. The best HQSAR model (VI-1) was derived from fragment distinction combination of atoms/bonds in fragment size, $7{\sim}10$bin. The herbicidal activities from atomic contribution maps showed that the activity will be able to increased according to the R-substituents variation of the N-phenyl ring and change of 6-chloro-2-benzoxazolyloxy group. Based on the results, the statistical results of the best HQSAR model (VI-1) exhibited the best pedictability and fitness for the herbicidal activities based on the cross-validated value ($q^2=0.646$) and non cross-validated value ($r^2_{ncv.}=0.917$), respectively. From the graphical analyses of atomic contribution maps, it was revealed that the lowest herbicidal activitics depends upon the 4-(6-chloro-2-benzoxazolyloxy)phenoxy group ($pred.pI_{50}=-3.20$). Particularly, the R=4-fluoro, X=isobutoxy substituent (P2) of (X)-phenoxy-N-(R)-phenylpropionamide derivative is predicted as the highest active compound ($pred.pI_{50}=9.12$).

• Journal of the Korean Chemical Society
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• v.38 no.9
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• pp.621-627
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• 1994

Two crystal structures of dehydrated, $Ag^{+}$ and $Ca^{2+}$-exchanged zeolite A treated at $250^{\circ}C$ with 0.15 torr of Cs vapor have been determined by single-crystal X-ray diffraction technique in the cubic space group $Pm{\bar\3m$ at $21(1)^{\circ}C$ (a = 12.344(2) $\AA$ and 12.304(2) $\AA$). Their structures were refined to the final error indices, R (weighted), of 0.091 with 180 reflections, and 0.093 with 179 reflections, respectively, for which I > $3\sigma(I).$ In each structure, Cs species are found at four different crystallographic sites: 3 $Cs^{+}$ ions per unit cell are located at 8-ring centers, ca. 6.81∼7.14 $Cs^{+}$ ions are found on opposite 6-rings on threefold axes in the large cavity, ca. 1.93∼2.03 $Cs^{+}$ ions are found on threefold axes in the sodalite unit, and 0.53∼0.66 $Cs^{+}$ ions lie on opposite 4-rings. Also, ca. 4.12∼4.27 Ag atoms are located near the center of the large cavity. In these structures, excess cesium atoms in a unit cell are associated with other $Cs^{+}$ ions on a single threefold axis to form the linear cationic cluster $(Cs_4)^{3+}$. By blocking 8-rings, the $Cs^{+}$ ions may have prevented silver atoms from migrating out of the structure. The Ag atoms are likely to have formed hexasilver clusters at the centers of the large cavities. Each hexasilver cluster is stabilized by coordination to 14 $Cs^{+}$ ions.

• Korean Journal of Food Science and Technology
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• v.2 no.1
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• pp.96-103
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• 1970

No foods are available commercially for weanling infants except a limited amount of expensive milk products in Korea. Although the majority of infants are breast-fed, when it is not possible, rice products must usually be substituted which is not sufficient in protein. Therefore, it is urgent to develop low-cost quality protein food mixtures. In order to accomplish this purpose three food mixtures (F-S-2, F-F-3 and F-P-4), consisting of rice (37∼46%), soybean (24∼40%), FPC (3∼7%), vitamins, minerals and other food additives, are developed. The food mixtures are white to light yellow in color; dispersed readily in water with water absorption index 320; viable bacterial population, less than $10^4$ per gram; sedimentation value, 63; Bostwick consistency value, 15cm/30%; and ring test value, 23cm/30%. The products contain 22∼25% protein and ensure reasonably balanced essential amino acids for the requirement of infants compared with FAO provisional pattern, Rao's maximum growth requirements and Holt's amino acid requirements in early life. Although threonine is limiting, protein score of F-P-4 formula is 93 based on the modified FAO provisional pattern (1965). Furthermore, a 100g of the products supplies required amounts of vitamins and minerals by the recommended daily dietary allowances for infants.

• Biomolecules & Therapeutics
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• v.24 no.6
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• pp.595-603
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• 2016

(E)-3-Phenyl-1-(2-pyrrolyl)-2-propenone (PPP) is a pyrrole derivative of chalcone, in which the B-ring of chalcone linked to ${\beta}$-carbon is replaced by pyrrole group. While pyrrole has been studied for possible Src inhibition activity, chalcone, especially the substituents on the B-ring, has shown pharmaceutical, anti-inflammatory, and anti-oxidant properties via inhibition of NF-${\kappa}B$ activity. Our study is aimed to investigate whether this novel synthetic compound retains or enhances the pharmaceutically beneficial activities from the both structures. For this purpose, inflammatory responses of lipopolysaccharide (LPS)-treated RAW264.7 cells were analyzed. Nitric oxide (NO) production, inducible NO synthase (iNOS) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) mRNA expression, and the intracellular inflammatory signaling cascade were measured. Interestingly, PPP strongly inhibited NO release in a dose-dependent manner. To further investigate this anti-inflammatory activity, we identified molecular pathways by immunoblot analyses of nuclear fractions and whole cell lysates prepared from LPS-stimulated RAW264.7 cells with or without PPP pretreatment. The nuclear levels of p50, c-Jun, and c-Fos were significantly inhibited when cells were exposed to PPP. Moreover, according to the luciferase reporter gene assay after cotransfection with either TRIF or MyD88 in HEK293 cells, NF-${\kappa}B$-mediated luciferase activity dose-dependently diminished. Additionally, it was confirmed that PPP dampens the upstream signaling cascade of NF-${\kappa}B$ and AP-1 activation. Thus, PPP inhibited Syk, Src, and TAK1 activities induced by LPS or induced by overexpression of these genes. Therefore, our results suggest that PPP displays anti-inflammatory activity via inhibition of Syk, Src, and TAK1 activity, which may be developed as a novel anti-inflammatory drug.

• Journal of the Korean Chemical Society
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• v.21 no.5
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• pp.307-319
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• 1977

The crystal structure of $N-({\alpha}-dimethyl\;{\beta}-hydroxy)ethyl\;N'-cyclohexyl\;thiourea,\;C_{ll}H_{22}N_2OS)$, has been determined by X-ray diffraction method. The compound crystallizes in the orthorhombic space group Pbca with a = 10.33(3), b = 11.82(3), c = 22.57(4)${\AA}$ and Z = 8. A total of 1414 observed reflections collected by the Weissenberg photographs and was solved by heavy atom method and refined by block diagonal least-squares methods to the R value of 0.13. The cyclohexane ring has a normal chair conformation and the thiourea unit is planar. The primary alcoholic group O-H bonded to C(l) makes an intramolecular hydrogen bond with N(2), which leads to stablize the molecule. There are two independent hydrogen bonds in the structure. One of them is of the type N-H${\cdot}{\cdot}{\cdot}$O intramolecular hydrogen bond with the length 2.71${\AA}$, another is of the type O-H${\cdot}{\cdot}{\cdot}$S intermolecular hydrogen bond with the length 3.21${\AA}$ parallel to the b axis. Apart from the hydrogen bonding system the molecules are held together by van der Waals forces in the crystal.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2342-2348
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• 2014

Poly(lactic-co-glycolic acid) (PLGA) were grafted to both ends of Pluronic$^{(R)}$ F68 ($(EO)_{75}(PO)_{30}(EO)_{75}$) triblock copolymer to produce poly{(lactic acid)$_m$-co-(glycolic acid)$_n$}-b-poly(ethylene oxide)$_{75}$-b-poly(propylene oxide)$_{30}$-b-poly(ethylene oxide)$_{75}$-b-poly{(lactic acid)$_m$-co-(glycolic acid)$_n$} (PLGA-F68-PLGA) pentablock copolymers. Molecular weights of PLGA blocks were controlled and five kinds of pentablock copolymers with different PLGA block lengths were synthesized using in-situ ring-opening polymerization of D,L-lactide and glycolide with tin(II) 2-ethylhexanoate ($Sn(Oct)_2$) catalyst. PLGA-F68-PLGA pentablock copolymers were characterized by $^1H$- and $^{13}C$-NMR, GPC, and TGA. The numbers (2m, 2n) of repeating units for lactic acid and glycolic acid inside PLGA segments were obtained as (48, 17), (90, 23), (125, 40), (180, 59), and (246, 64), with $^1H$-NMR measurement. From NMR data, the resultant molecular weights were determined in the range of 12,700-29,700, which were similar to those obtained from GPC. Polydispersity index was increased in the range of 1.32-1.91 as the content of PLGA blocks increased. TG and DTG thermograms showed discrete degradation traces for PLGA and F68 blocks, which indicate the weight fractions of PLGA blocks in pentablock copolymers can be calculated by TG profile and it is possible to remove PLGA block selectively. Hydrodynamic radius and radius of gyration of pentablock copolymer micelle were obtained in the range of 46-68 nm and 31-49 nm, respectively, in very dilute (i.e. 0.005 wt %) aqueous solution of THF:$H_2O$ = 10:90 by volume at $25^{\circ}C$.