• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1272-1287
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• 2002

Sonochemical Reformatsky reaction of aldehydes or ketones with ethyl bromoacetate in the presence of indium afforded $\beta-hydroxyesters$ in good to excellent yields under mild conditions. 2- or 3-Hydroxybenzaldehyde that contains an acidic hydrogen r eacted with ethyl bromoacetate to provide the desired compounds with the same efficiency. In the case of ethyl 2-bromopropanoate and ethyl 2-bromo-2-methylpropanoate, the desired products were obtained in good yields. Reaction of aldehyde with indium reagent in the presence of ketone group proceeded chemoselectively.

• Bulletin of the Korean Chemical Society
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• v.26 no.6
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• pp.878-879
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• 2005

• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.69-77
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• 1998

(3S,4S)-1-(t-Butoxycarbonylmethyl)-3-[(S)-1-(t-butyldimethylsilyloxy)ethyl]-4-(2-diazo-2-ethoxycarbonyl-1-oxoethyl)-2-azetidinone (14) was prepared from 4-styryl-2-azetidinone 7b via a sequence of reactions involving N-alkylation with bromoacetate, ozonolysis, oxidation, condensation with magnesium ethyl malonate, and diazo transfer reaction. (3S,4S)-3-[(S)-1-(t-Butyldimethylsilyloxy)ethyl]-4-(3-diazo-3-ethoxycarbonyl1-hydroxypropyl)-2-azetidinone (21) was also prepared from 4-formyl-2-azetidinone 5b via a sequence of reactions involving Wittig reaction, 1,3-dipolar cycloaddition with ethoxycarbonylformonitrile oxide, catalytic hydrogenation, and diazotization. However, the final cyclization of 14 or 21 to 1-hydroxycarbapenem or 1-hydroxycarbapenam by treating with $Rh_2(OAc)_4$ was unsuccessful.

• YAKHAK HOEJI
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• v.37 no.2
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• pp.113-118
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• 1993

3-Phenyl-5, 6, 7, 8-tetrahydrothiazolo[3, 2-$\alpha$][1, 3]diazepine, which has pharmaceutical activities, was reacted with phenyl isothiocyanate to give 3-phenyl-9-phenyl(thiocarbamoyl)-5, 6, 7, 8-tetrahydrothiazolo[3, 2-$\alpha$][1, 3]diazepi nium-betaine. New biheterocyclic compounds were prepared by the ring transformation reaction of the above reactive betaine with $\alpha$-haloesters and $\alpha$-haloketones such as ethyl bromoacetate, methyl bromoacetate, chloroacetone, and 4'-methoxyphenacyl bromide, respectively. In each ring transformation reaction, two major products supposed to be geometrical isomers were obtained.

• Archives of Pharmacal Research
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• v.26 no.9
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• pp.686-696
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• 2003

Ethyl (coumarin-4-oxy)acetate 1 was prepared through the reaction of 4-hydroxycoumarin with ethyl bromoacetate. Compound 1 was allowed to react with hydrazine hydrate to produce coumarin-4-oxyacetic hydrazide 2. The synthesis of N-(arylidene and alkylidene)-coumarin-4-oxyacetic hydrazones 3-20 was performed. The preparation of 2-substituted-3-[(coumarin-4-oxy) acetamido]thiazolidinones 21-26 and 2-[(coumarin-4-oxy )methyl]-4-acetyl-5-substituted-$\Delta^2$-1,3,4-oxadiazolines 27-33 was performed by the reaction of the hydrazones 3, 4, 7, 9, 12, 14 with mercaptoacetic acid and the hydrazones 3, 4, 5, 7, 12, 15, 16 with acetic anhydride, respectively. The antiviral activities, cytotoxicities and structure-activity relationship (SAR) towards different microorganisms of the prepared compounds were studied.

• Bulletin of the Korean Chemical Society
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• v.16 no.2
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• pp.153-157
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• 1995

Calix[6]arenes are selectively dialkylated at the lower rim and further functionalized by the aminomethylation and Claisen Rearrangement reactions. Dialkylation was conducted by the reaction of calix[6]arene and alkyl halides such as benzyl bromide, allyl bromide, ethyl bromoacetate, propyl bromide, and methyl iodide under the carefully controlled reaction conditions. Aminomethylation was carried out with the treatment of disubstituted calix[6]arene and secondary amine in the presence of formaldehyde. Claisen rearrangement reaction of the O-diallylcalix[6]arene produced the p-diallylcalix[6]arene.

• Archives of Pharmacal Research
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• v.12 no.1
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• pp.17-21
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• 1989

We have reported earlier on the reactivity of 7-dithiocarboxy-3-phenyl-5,6-dihydro imidazo[2,1-b]thiazolium-betaine with several para-substituted phenacyl bromides. In this work reactions of 7-dithiocarboxy-3-phenyl(or methyl)-5,6-dihydro imidazo[2,1-b]thiazolium-betaine with a series of aliphatic alkylating agents of ${\alpha}$ -halo ketone,${\gamma}$-halo koto ester and ${\alpha}$ -halo ester were examined for the similar purpose. In case of ${\alpha}$-halo ketone or ${\gamma}$-halo koto ester such as ${\alpha}$ -chloro acetone or ethyl 4-chloro acetoacetate new biheterocyclic compound was obtained via ring transformation reaction. However, reaction of the betaine with methyl(or ethyl) bromoacetate used as a ${\alpha}$-halo ester, gave, in-stead, S-alkylated quarternary ammonium salt.

• Journal of Integrative Natural Science
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• v.9 no.2
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• pp.86-93
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• 2016

The peptide sequences, GHK(Gly-His-Lys) and KTTKS(Lys-Thr-Thr-Lys-Ser), using a collagen stimulator recently were manipulated at N-terminal as a multifunctional peptide derivative with PEG(polyethyleneglycol) linker connected to gallic acid which presents anti-inflammatory activity. The multifunctional peptide derivatives were obtained in a normal peptide preparation method through SPPS(solid phase peptide synthesis) using Fmoc chemistry and a carboxyl group insertion reaction of PEG-3,4,5-triacetoxy benzoate by using potassium tert-butoxide and ethyl bromoacetate, which was separated by Sephadex DEAE. It gave a good compromise to a cosmetic application for cell cytotoxicity, anti-wrinkle, and anti-inflammation.

• Bulletin of the Korean Chemical Society
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• v.20 no.8
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• pp.905-909
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• 1999

Reaction of tetrahomodioxa p-phenylcalix[4]arene with ethyl bromoacetate and potassium carbonate in ace-tone leads to the title tetra ester derivative, 7,13,21,27-tetra-phenyl-29,30,31,32 -tetrakis(ethoxycarbonyl)meth-oxy-2,3,16,17-tetrahomo-3,17-dioxacalix[4]arene, its structure was determined by NMR spectra as 1,4-alternate conformation. The molecular structure has been solved by X-ray diffraction methods. The molecule has a conformation with pseudo center of symmetry. The benzene ring A is up, ring C is down, B and D rings are flat with respect to the plane of the macrocyclic ring.