• YAKHAK HOEJI
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• v.36 no.2
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• pp.126-128
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• 1992

A new method for felbinac, which is a potent anti-inflammatory agent, is described. Friedel-Crafts reaction of biphenyl with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)acetate(1)$ afforded ethyl 2-methylthio-2-(4-biphenylyl)acetate(4). Felbinac (7) was synthesized by desulfurization of compound (4) with zinc dust in acetic acid, followed by hydrolysis of the resultant ethyl 2-(4-biphenylyl)acetate (6).

• YAKHAK HOEJI
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• v.36 no.2
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• pp.137-139
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• 1992

A new method for xenbucin, which is a antihypercholesteremic agent, is described. Friedel-Crafts reaction of biphenyl with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)acetate(1)$ afforded ethyl 2-methylthio-2-(4-biphenylyl)acetate(2). Ethyl 2-(4-biphenylyl)butyrate(4) was obtained by ethylation of (2) with NaH and $C_2H_5I$, followed by desulfurization of the resultant ethyl 2-methylthio-2-(4-biphenylyl)butyrate(3) with zinc dust in acetic acid. Xenbucin was synthesized by hydrolysis of (4).

• Bulletin of the Korean Chemical Society
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• v.21 no.4
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• pp.441-445
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• 2000

A new series of three ring type liquid crystalline compounds containing partially fluorinated alkenyl or alkyl side chains together with fluorine substituted cyclohexylbiphenyls were designed and synthesized in this study. The structures of synthe sized compounds were established by 1 H, 13 C and 19 F NMR spectroscopy. The phase transition temperatures of fluorinated liquid crystalline compounds were determined by cross-polarizing mi-croscopy equipped withhot stage. All compounds were found to have nematic liquid crystalline phase with rel-atively low phase transition temperature and wide liquid crystalline temperature range. The dependence of phase transition temperatures on the chainlength falls into three categories; (a) decreasing transition tempera-tures for 4-fluoro-4'-[4-fluoro-4-(1-fluoroalkyl)cyclohexyl]biphenyl (15) series, (b) higher transition tempera-tures for odd numbered chains for 4-fluoro-4'-[4-fluoro-4-(1-fluoroalk-1-enyl)cyclohexyl]biphenyl (14) series, (c) higher transition temperatures for even numbered chains for 4-[4-(1,2-difluoroalk-1-enyl)-4-fluorocyclo-hexyl]-4'-fluorobiphenyl (16) series.

• Bulletin of the Korean Chemical Society
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• v.10 no.6
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• pp.509-514
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• 1989

Reactions of thianthrene cation radical perchlorate (1) with N-(p-methoxyphenyl)benzenesulphonamide (14) in acetonitrile at room temperature afforded various products : thianthrene (3), N-(p-hydroxyphenyl)benzenesulphonamide (16), benzenesulphonamide (18), hydroquinone (20); 5-(5-benzenesulphonamido-2-methoxyphenyl)-thia nthrenium perchlorate(21), 2-benzenesulphonamido-2'-hydroxy-5,5'-dimethoxy biphenyl(24), 2-benzenesulphonamido-2',5'-dihydroxy-5-methoxy -biphenyl(25), and a traceable amount of p-quinone(23). The formations of part of (3) and (21) can be explained by either disproportionation or half-regeneration mechanism but those of the remainders by diverse reactions of sulphonamidyl radical (27) derived from (14) (through single electron transfer, followed by deprotonation processes). Similar results were observed from the reaction with N-(p-methoxyphenyl)methanesulphonamide (15).

• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1487-1492
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• 1999

The kinetics of oxidation of substituted styryl 4-biphenyl ketones and of substituted styryl 2-fluorenyl ketones by pyridinium chlorochromate (PCC) have been studied in 90% acetic acid- 10% water (v/v) containing perchloric acid and NaClO₄ at $10^0,\;20^0,\;30^0$ and 40℃. The reactions are first order in styryl ketones and PCC. The second order rate constants are well correlated only with σ$^+$ constants implying development of positive charge adjacent to benzene ring in the transition state. The effects of varying [HClO₄] and the percentage of acetic acid on the reactions have also been analysed. A mechanism involving nucleophilic attack of PCC leading to an unsymmetric intermediate from which epoxides are formed is proposed.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.132.1-132.1
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• 2003

Biphenyl dimethyl dicarboxylate (DDB) is a by-product produced in process of synthesizing Schizandrin-C. Generally, DDB has known to protect hepatocytes and to decrease the index of liver enzyme (e.g. GOT and GPT) in chronic hepatitis. The present study was aimed to demonstrate whether DDB can protect the brain cell, especially the Alzheimer brain in vitro. As Alzheimers disease can be induced by activated microglia, a macrophage in the brain, through Abeta peptide (A$\beta$) produced from amyloid precursor protein (APP). (omitted)

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.142-142
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• 1998

This study has been undertaken to examine the effect of biphenyl dimethyl dicarboxylate (DDB) on rat liver drug metabolizing enzyme in order to understand the mechanism of DDB on improving hepatic toxicity in rat liver. After DDB was administered into male rats for different periods of time, mRNA level of CYP1A1 and CYP2B1 was measured by polymerase chain reaction (PCR). DDB treatment resulted in increase in CYP2B1 mRNA level whereas there was no change in CYP1A1 mRNA level. This effect of DDB was time dependent reaching maximal level by 2-day treatment. DDB dose response study showed that 50mg/kg DDB induced CYP2B1 mRNA to maximal level and DDB icreased CYP2B1 gene expression with dose-dependent manner. Based on studies of lipid peroxidation, serum ALT and AST levels and histopathologic examination showed DDB protection on CCl4 induced hepatotoxiccity.

• Bioindustry News
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• v.11 no.3
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• pp.15-20
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• 1998

• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.933-934
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• 2002

• Proceedings of the PSK Conference
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• 2001.04a
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• pp.173.2-173.2
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• 2001