• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.188-191
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• 1993

The reaction between methyl 2,3-di-O-benzyl-4,6-di-O-mesyl-${\alpha}$-D-glucopyranoside (1b) and potassium superoxide resulted in hydrolysis, and gave methyl 2,3-di-O-benzyl-${\alpha}$-D-glucopyranoside (1) as a sole product. When the reaction was performed with a vicinal dimesylate, methyl 4,6-O-benzylidene-2,3-di-O-mesyl-${\alpha}$-D-altropyranoside (4b), again the hydrolysis product, methyl 4,6-O-benzylidene-${\alpha}$-D-altropyranoside (4) was obtained. However, the reaction of potassium superoxide with another vicinal dimesylate, methyl 4,6-O-benzylidene-2,3-di-O-mesyl-${\alpha}$-D-glucopyranoside (3b), nucleophilic displacement took place to afford methyl 4,6-O-benzylidene-${\alpha}$-D-altropyranoside (4). Apparently different results from two trans vicinal dimesylates, 3b and 4b are explained by the transient formation of epoxides, methyl 2,3-anhydro-4,6-O-benzylidene-${\alpha}$-D-allopyranoside (8) and methyl 2,3-anhydro-4,6-O-benzylidene-${\alpha}$-D-mannopyranoside (9) by $KO_2$. The reaction between the allo epoxide 8 and $KO_2$ gave altro 4. The manno epoxide 9 also afforded altro 4 as the major product. Facile epoxide formation by the reaction of a vicinal dimesylate and superoxide was also observed with 3-O-benzyl-1,2-O-isopropylidene-5,6-di-O-mesyl-${\alpha}$-D-glucofuranose: 5,6-anhydro-3-O-benzyl-1,2-O-isopropylidene-${\beta}$-L-idofuranose was obtained.

• Journal of the Korean Chemical Society
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• v.60 no.2
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• pp.107-110
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• 2016

A new series of hydrazino thiazolyl-2-azetidinone 4(a-i) derivatives were synthesized efficiently using benzylidene hydrazinyl thiazole derivatives 3(a-i). The precursors, benzylidene hydrazinyl thiazoles were prepared by reacting 4-fluoro phenacyl bromide with thiosemicarbazones 2(a-i). All the structures of the synthesized compounds were ascertained by IR, NMR and mass spectral analysis.

• Journal of Pharmaceutical Investigation
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• v.22 no.1
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• pp.23-31
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• 1992

A novel O-diethylaminoethyl chitosan (DEAE-chitosan) was synthesized via Schiff's reaction between chitosan and benzaldehyde. $C_2$ amino group was protected via Schiffs base reaction with benzaldehyde to form N-benzylidene chitosan. After reaction with diethylaminoethyl chloride, Schiffs base was removed by reacting O-diethylaminothyl-N-benzylidene chitosan and hydrochloric acid. Tensile strength of DEAE-chitosan was improved due to the incorporation of bulky side group in $C_6$ position of chitosan. DEAE-chitosan showed a pH-dependent swelling characteristics. Release rate of riboflavin was dependent on the water content of DEAE-chitosan that is a function of crosslinking degrees.

• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.94-98
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• 2013

A new family of thiazole heterocycles, namely [4-(1H-benzoimidazol-2-yl)-thiazol-2-yl]-benzylidene-amines has been synthesized by the condensation of 4-(1H-Benzoimidazol-2-yl)-thiazol-2-ylamine with various aromatic aldehydes and N-[4-(1H-benzoimidazol-2-yl)-thiazol-2-yl]-N'-benzylidene-hydrazines through the cyclization of 1-(1H-benzoimidazol-2-yl)-2-bromo-ethanone with arylthiosemicarbazones. The target compounds are achieved by using 1-(1H-Benzoimidazol-2-yl)-ethanone as starting material. The chemical structures of all newly synthesized compounds were confirmed by their IR, $^1H$ NMR and Mass spectral data. Further the compounds were used to evaluate their antimicrobial activity and found that the appreciable antimicrobial activity by some of the title compounds.

• Journal of the Korean Chemical Society
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• v.51 no.6
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• pp.506-512
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• 2007

Various long chain aliphatic acid hydrazides react with aromatic and heterocyclic aldehydes in alcoholic medium in refluxing conditions to give corresponding 2-hydroxy benzylidene and 1H-indol-3-ylmethylene hydrazides, a newer class of mosquito para-pheromones. We describe here synthesis of various novel long chain aliphatic acid (2- hydroxy benzylidene and 1H-indol-3-ylmethylene) hydrazides by conventional as well as microwave irradiation techniques. The structures of these compounds have been confirmed by spectroscopic techniques (FTIR, NMR & MS). Some of the interesting features of the electron impact mass spectral fragmentation pattern of these compounds have also been discussed.

• Korean Journal of Crystallography
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• v.16 no.1
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• pp.6-10
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• 2005

A novel potential linking ligand (4-nitro-benzylidene)-(3-nitro-phenyl)-amine (1) was prepared from 4-nitrobenzaldehyde and 3-nitroaniline by the Schiff-base condensation. From the reaction between 1 and dichlorobis(benzonitrile)palladium (II) $(PdCl_2(NCPh)_2)$, an unexpected product $trans-PdCl_2(NO_2-C_6H_4-NH_2)_2$ (2) was isolated. Compounds 1 and 2 were structurally characterized by X-ray diffraction. In compound 2, the $NH_2$ hydrogen atoms in the 3-nitroaniline ligand participate in intermolecular N-H${\cdot}\;{\cdot}\;{\cdot}\;$Cl hydrogen bonds.

• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.78-83
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• 1998

It's necessary to develope a facile methodology forming ${\alpha}$-altropyranosidic linkage, for the synthesis of trisaccharide repeating unit of O-antigenic part of Campylobacter jejuni gram negative bacteria. In this paper, the effective synthesis of disaccharides containing ${\alpha}$-altropyranosidic linkage by 1,2-trans glycosidation of allal derivatives was discussed. 4, 6-O-Benzylidene-3-O-(t-butyldimethylsilyl)-D-allal was treated with DMDO (3,3-dimethy ldioxirane) to yield 1,2-anhydro-4, 6-O-benzylidene-3-O-(t-butyldimethylsilyl)-${\beta}$-D-altropyranose. The reaction of 1,2-anhydro-4, 6-O-benzylidene-3-O-(t-butyldimethylsilyl)-${\beta}$-D-altropyranose with allyl alcohol gave allyl 4, 6-O-benzylidene-3-(t-butyldimethylsilyl)-${\alpha}$-D-altropyranoside quantitatively, and reactions with glucals were also successful to prepare ${\alpha}$-altropyranosodic disaccharides. It is convinced that 1,2-trans glycosidation of allal derivatives should be an attractive choice for preparing oligosaccharides containing ${\alpha}$-altropyranosidic linkages.

• Journal of the Korean Chemical Society
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• v.33 no.6
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• pp.614-622
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• 1989

The electrochemical reduction of ${\alpha},{\beta}$-dibenzyl N-benzylidene L-aspartate in 0.1M LiCl ethanol solution was investigated by direct current (DC), differential pulse (DP) polarography, cyclic voltammetry and controlled potential coulometry(CPC). The irreversible reductive amination of imino group proceeded to form ${\alpha},{\beta}$-dibenyl N-benzyl L-aspartate by CEC or CE electrochemical reaction mechanism at the first reduction step (-0.92 volts vs. Ag-AgCl). The polarographic reduction wave was slightly suppressed due to inhibitory effect of micelle, while the irreversibility was increased according to the increase of Triton X-100 concentration. Upon the basis of product analysis and polarogram interpretation with pH change, possible CE electrode reaction mechanism was suggested.

• Textile Coloration and Finishing
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• v.26 no.2
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• pp.143-149
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• 2014

The designed dye material, namely 2-(4-(9H-carbazol-9-yl)benzylidene) compound, was synthesized. After the reaction, the solid was filtered and purified by recrystalization with acetone/water. To confirm and analyze its synthesis and structural formation, the single crystal was prepared and its measurement was carried out. A yellow needle crystal of $C_{22}H_{13}N_3$ were made on a Rigaku R-AXIS RAPID diffractometer using graphite monochromated CuK${\alpha}$ radiation. All details were suggested and introduced to support and communicate this study.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3289-3294
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• 2013

An efficient method for the preparation of 8-benzylidene-4-phenyl-3,4,5,6,7,8-hexahydro-1H-quinazolin-2-ones/thiones from the reaction of aromatic aldehydes with cyclohexanone and urea or thiourea in the presence of Tetrabutylammonium hexatungstate, $[TBA]_2[W_6O_{19}]$, as an efficient, inexpensive catalyst under thermal and solvent-free conditions has been developed. Good yields, short reaction times, straightforward workup, reusability of the catalyst, and green conditions are the most obvious advantages of this procedure.