• Applied Chemistry for Engineering
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• v.10 no.7
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• pp.1079-1085
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• 1999

An investigation was made of the effect of various transition metal catalysts, ligands, and a promoter on the synthesis of N,N'-diphenylurea(DPU) from nitrobenzene, aniline, and carbon monoxide. Homogeneous Pd and Ni catalysts were found to be highly efficient, giving almost quantitative isolated DPU yields at 100% nitrobenzene conversion. Bidentate ligand, 1,3-bis(diphenylphosphino)proane(dppp) showed much improved activity and significantly different reactivity relative to the usual monodentate $PPh_3$ ligand in the presence of Ni and Pd catalysts. These results were inferred to the effect of the cis coordination of bidentate dppp ligand on the metal. The use of a promoter $Et_4NCl$ was indispensable in the case of $PPh_3$, yet inhibited the reaction if used with dppp. It was possible to reuse the Pd-dppp catalyst system, although the catalytic activity was reduced slowly.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.269-272
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• 2014

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.296-298
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• 2011

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1204-1206
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• 2009

• Bulletin of the Korean Chemical Society
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• v.28 no.2
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• pp.311-314
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• 2007

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2381-2386
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• 2013

A new series of Mn(II) and Mo(VI) complexes containing the Schiff bases hydrazinecarbothioamide and hydrazinecarboxamide of 5,6-dimethyl-1H-indol-2,3-dione have been synthesized. The nature of bonding and the stereochemistry of the complexes have been deduced from elemental analyses, molecular weight determinations and spectral studies viz. electronic IR, ESR, $^1H$ NMR and $^{13}C$ NMR and X-ray diffraction spectral studies. The magnetic moment values of the manganese(II) complexes are in the range of 5.80-6.15 B.M. suggesting a high spin state of manganese in these complexes. The spectral data are consistent with a tetrahedral geometry around Mn(II) and an octahedral geometry for Mo(VI), in which the ligands act as bidentate chelating agents, coordinated through the nitrogen and sulfur/oxygen atoms. The ligands and their metal complexes have been tested against a number of pathogenic fungi and bacteria at different concentrations and were found to possess sufficient fungicidal and bactericidal properties. Further, the complexes were also tested for their antifertility activity in male albino rats and the results were indeed positive.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.1000-1006
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• 2011

The discovery of carbohydrate-based bioactive compounds has recently received considerable interest in the drug development. This paper stresses on the application of 1-methoxy-O-glucoside as the central scaffold, whereas salicylic pharmacophores were introduced with diverse spatial orientations probing into the structural preference of an enzymatic target, i.e. protein tyrosine phosphatase 1B (PTP1B). By employing regioselective protection and deprotection strategy, 2,6-, 3,4-, 4,6- and 2,3-di-O-propynyl 1-methoxy-O-glucosides were previously synthesized and then coupled with azido salicylate via click chemistry in forming the desired bidentate salicylic glucosides with high yields. The inhibitory assay of the obtained triazolyl derivatives leads to the identification of the 2,3-disubstituted salicylic 1-methoxy-O-glucoside as the structurally privileged PTP1B inhibitor among this bidentate compound series with micromole-ranged $IC_{50}$ value and reasonable selectivity over other homologous PTPs tested. In addition, docking simulation was conducted to propose a plausible binding mode of this authorized inhibitor with PTP1B. This research might furnish new insight toward the construction of structurally different bioactive compounds based on the monosaccharide scaffold.

• Journal of Species Research
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• v.5 no.3
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• pp.355-358
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• 2016

A spionid polychaete, Scolelepis (Scolelepis) kudenovi Hartmann-Schroder, 1981, is newly reported from Korean waters with description and illustration. Scolelepis (Scolelepis) kudenovi is characterized by a combination of the following morphological features: the notopodial setae are present on the setiger 1; the occipital tentacle is absent; the branchiae are partially fused to the notopodial postsetal lamellae; the notopodial and neuropodial hooded hooks are bidentate only; the notopodial hooded hooks are present on the posterior setigers. A key to Scolelepis species from Korean waters is provided in this paper.

• Journal of the Korean Chemical Society
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• v.12 no.1
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• pp.12-17
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• 1968

A series of octahedral cobalt(III) complexes involving quadridentate bissalicylaldehyde ethylenediimine (SAED) chelating ligand have been prepared as a new compound: [$Co(SAED)X_2]^+,$ where X = ammonia, pyridine, and bidentate ethylenediamine. Properties and configuration of the complexes were studied by the chemical and physical method.

• Bulletin of the Korean Chemical Society
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• v.16 no.5
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• pp.439-443
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• 1995

Both enantiomers of (S)-(-)-2-(diphenylphosphino)-2'-mercapto-1,1'-binaphthyl and their derivatives were obtained by synthesis from racemic 2,2'-dihydroxy-1,1'-binaphthyl and subsequent resolution. The utilities of these ligands were investigated briefly. And among these, S-methyl derivative 15 has proved to be an effective ligand for Pd-catalyzed allylic alkylation.