• Archives of Pharmacal Research
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• v.17 no.1
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• pp.17-20
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• 1994

Friedel-Crafts reaction of fluorene with methyl ${\alpha}$-chloro-${\alpha}$-(methylthio)acetate 1 gave methyl $\alpha$-methylthio-2-fluoreneacetate 2. Cicloprofen 8, a potent antiinflammatory agent, was prepared by methylation of 2 followed by reductive desulfurization of methyl 2(2-fluorenyl)-2-(methylthio)propionate 6 and hydrolysis of methyl 2-(2-fluorenyl)propionate 7.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3156-3158
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• 2010

Stable and non-hygroscopic polystyrene supported aluminium triflate (Ps-$Al(OTf)_3$), which is prepared easily from cheap and commercially available compounds was found to be an environmentally friendly heterogeneous catalyst for Friedel-Crafts acylation of arenes using acid chlorides in the absence of solvent under mild reaction conditions. The catalyst can be reused up to five times after simple washing with dichloromethane.

• Journal of the Korean Chemical Society
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• v.46 no.4
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• pp.384-389
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• 2002

• Bulletin of the Korean Chemical Society
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• v.2 no.3
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• pp.83-85
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• 1981

Tetrachlorocyclopropene has been prepared smoothly by the dehydrochlorination of pentachlorocyclopropane which could be obtained easily from sodium trichloroacetate and trichloroethylene in 1,2-dimethoxyethane. By the reaction of aromatic hydrocarbons with tetrachlorocyclopropene and aluminium chloride, new substituted phenyltrichlorocyclopropene derivatives have been prepared. The structures of these compounds were characterized by means of spectroscopic methods.

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2594-2596
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• 2013

Highly chemo- and regioselective reaction of hydroxybenzenes with ${\alpha},{\beta}$-unsaturated compounds in acidic ionic liquid l-butyl-3-methylimidazolium hydrogen sulphate ([BMIM]HSO4) was reported for the first time. A series of oxa-Michael adducts and Friedel-Crafts alkylated products were synthesized with good yields. The acidic ionic liquid could be easily recycled for at least 5 times with only minor loss in activity.

• 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.33 no.4
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• pp.237-240
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• 1989

A new synthetic method for tiaprofenic acid, which is a potent anti-inflammatory agent, was described. Friedel-Crafts reaction of thiophene with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)$ acetate (1) gave ethyl ${\alpha}-methylthio-2-thiopheneacetate$ (3). Ethyl ${\alpha}-methyl-2-thiopheneacetate$ (5) was prepared by treatment of (3) with NaH and MeI, followed by desulfurization with zinc dust-acetic acid of the resultant ethyl ${\alpha}-methyl-{\alpha}-methylthio-2-thiopheneacetate$ (4). Tiaprofenic acid (7) could be easily synthesized by benzoylation of (5) and hydrolysis of the resultant ethyl $5-benzoyl-{\alpha}-methyl-2-thiopheneacetate$ (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).

• Archives of Pharmacal Research
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• v.16 no.4
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• pp.343-346
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• 1993

A new method was described for the preparation of 7-[p-(methylthio)benzoyl]-5-benzofuranacetic acid 6, which is an analgestic agent. Methyl 5-(2, 3-di-hydobenzofuran)acetate 3 was obtained by Friedel-Crafts reaction of 2, 3-dihydrobenzofuran with methyl .alpha.-chloro-.alpha.(methylthio)actate 1 and desulfurization of 2. Tifurac 6 was synthesized from acylation of 3 with p-(methythio)benzoyl chioride followed by bromination of 4, dehydrohalogenation, and hydrolysis of 5.

• Archives of Pharmacal Research
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• v.19 no.2
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• pp.148-152
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• 1996

The efficient synthesis of 4-(2-thiazolyloxy)phenylalkanoic acids (10a-c), which are a potent antiinflammatory agent, was achieved in 5-6 steps starting from isopropoxybenzene and methyl $\alpha-chloro-\alpha-(methylthio)acetate (1)$. The key intermediate (4) was prepared by Friedel-Crafts reaction of isopropoxybenzene with (1) followed by desulfurization and the removal of isopropyl protector. Methyl 4-hydroxyphenylalkanoates (6, 8) were similarly obtained from alkylation of (3) and deprotection.