• Journal of the Korean Applied Science and Technology
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• v.8 no.1
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• pp.45-49
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• 1991

The synthesis of urocanic acid which was started D-fructose, and its alkyl esters, urocanic ethyl ester and urocanic isobutyl ester, were prepared by esterificated. Urocanic ethyl ester and urocanic isobutyl ester were insoluble in water and soluble most organic solvents (ethanol, benzene, toluene, pyridine, THF, DMF) which adds to their practical applicability, and absorb ultraviolet light of greater wavelength than the free acid and there by are more effective for shielding sensitive materials, including the humanbody, from the chemically most effective portion of the solar ultraviolet spectrum.

• YAKHAK HOEJI
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• v.35 no.4
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• pp.332-334
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• 1991

The synthesis of melandrin has been accomplished in good yield by the reaction of 5-tosyloxyanthranilic acid ethyl ester with p-acetoxybenzoyl chloride, followed by removal of protecting groups with methanolic ammonia.

• YAKHAK HOEJI
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• v.28 no.1
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• pp.17-20
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• 1984

Synthetic procedures to synthesize fenbufen-acetaminophen ester were searched by acid chloride method, DCC method and mixed acid anhydride method. The compound was synthesized by DCC method and mixed acid anhydride method but could not be synthesized by acid chloride method. Its anti-inflammatory activity was superior to acetaminophen and similar to fenbufen.

• Archives of Pharmacal Research
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• v.28 no.2
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• pp.129-141
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• 2005

(-)-Fumagillol (1), a hydrolysis product of fumagillin, has been synthesized by several group from commercially available 1,2:5,6-di-O-isopropylidene-${\alpha}$-D-allofuranose in a highly stereoselective manner. Chiral centers on C5 and C6 came from D-allofuranose and the asymmetric center on C4 was accomplished by 1,3-chirality transfer using the Claisen rearrangement on a chiral allyl alcohol. Chirality, which is necessary on an epoxide consisting of the spiro-ring system, was diastereoselectively constructed by the well-known reaction, intramolecular ester enolate alkylation (IEEA), which showed that this reaction can be applied to the alpha-alkoxy ester system. The epoxide on the side chain was regioselectively introduced by the difference between the number of substituents on the vinyl groups. This accomplishment proved that IEEA can be a useful tool for the synthesis of complex molecules.

• Archives of Pharmacal Research
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• v.9 no.4
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• pp.237-242
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• 1986

The Synthesis of E, E, E-12-fluorofarnesol and E, Z-6-fluorofarnesol which are key intermediates for the study of biosynthesis of some sesquiterpenes, is described. E, E-Farnesyl acetate is treated with selenium dioxide to give E, E, E-12-hydroxy farnesyl acetate, whih is transformed by DAST into E, E, E-12-hydroxy farnesyl acetate, which is transformed by DAST into E, E, E,-12-fluorofarnesylacetate. The latter compound is hydrolyzed to E, E, E,-12-fluorofarnesol. The reformatsky reaction of 6-methyl-5-hepten-2-one with ethyl bromofluoroacetate affords ethyl 2-fluoro-3-hydroxy-3, 7 dimethyl-6-octanoate. This ester is acetylated and eliminated to give ethyl (Z)-2-fluoro-3, 7-dimethylocta-2, 6-dienoate, which is transformed to allyl bromide via allylic alcohol. The allyl bromide is treated with dianion of methyl acetate to give-keto ester. The $\beta$-keto ester is converted to diethyl phosphoryloxy compound. The conjugate addition of lithium dimethylcuprate to the latter compound gives fluoro ester, which is treated with DIBAL to afford E, Z-6-fluorofarnesol.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2776-2782
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• 2010

Newly developed Horner-Wadsworth-Emmons (HWE) reagents 5 having triphenylphosphorane ylide subunits readily condensed with various carbonyl compounds under mild reaction conditions to afford $\beta,\gamma$-unsaturated $\alpha$-keto triphenylphorane ylides in good to excellent yields, which were hydrogenated over Pd-C (10%)/$H_2$ (1 atm) to give the corresponding $\alpha$-keto triphenylphorane ylides in quasi-quantitative yields. These triphenyphosphorane ylides have been utilized as the precursors to $\alpha$-keto amide/ester and vicinal tricarbonyl units in Wasserman's synthetic protocols, and have previously been prepared only from carboxylic acids/acid chlorides. Our new approaches provide excellent alternatives for the synthesis of triphenylphosphorane ylide precursors to $\alpha$-keto amide/ester and vicinal tricarbonyl units directly from carbonyl compounds in good to excellent yields.

• YAKHAK HOEJI
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• v.47 no.5
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• pp.331-338
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• 2003

A butyrolactone ester of cefazolin (CFZ-BTL) was synthesized by the esterification of cefazolin (CFZ) with $\alpha$-bromo-${\gamma}$-butyrolactone. The synthesis was confirmed by the spectroscopic analysis. The CFZ-BTL was more lipophilic than the CFZ when assessed by n-octanol/water partition coefficients at various pH. The CFZ-BTL itself did not show any antimicrobial activity in vitro, but after oral administration of CFZ-BTL to rabbits, exerted significant anti-microbial activity in serum samples when measured by the inhibion zone method in nutrient agar plates, due to conversion of CFZ-BTL to an active metabolite, probably CFZ, in the body. The CFZ-BTL was also converted into CFZ as confirmed by in vitro incubation study, with tissue homogenates (liver, blood and intestine) of rabbits. The liver showed the fastest conversion rate, probably via the hydrolysis mechanism. In vivo metabolism of CFZ-BTL to CFZ was also confirmed in vivo serum samples by HPLC. The oral bioavailability of CFZ-BTL in rabbits was 1.6-fold increased when compared to CFZ, resulting from followed by enhanced lipophilicity increased passive absorption in the intestine.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1443-1459
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• 2019

Polyglycerol fatty acid ester nonionic surfactants have been used for a long time in foods and have been suggested as an alternative to the safety problems of PEG based nonionic surfactants. The polyglycerol fatty acid ester surfactants are synthesized by combining a hydrophilic polyglycerin and a lipophilic fatty acid. The hydrophilic polyglycerin is polymerized using glycerin, glycidol, epichlorohydrin, etc. The main issues of the polyglycerol polymerization reaction are to increase the content of the polyglycerol in the form of linear rather than branched or cyclic forms and to narrow the distribution of the degree of polymerization. The method of binding a lipophilic fatty acid group to a hydrophilic polyglycerin includes chemical synthesis such as esterification reaction and enzyme synthesis using lipase enzyme. The main issues of polyglycerin fatty acid ester synthesis are to increase the yield and to control the degree of esterification while reducing side reactions.

• Proceedings of the Korean Fiber Society Conference
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• 2001.04a
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• pp.189-192
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• 2001

• Bulletin of the Korean Chemical Society
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• v.22 no.3
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• pp.327-329
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• 2001