• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.1819-1820
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• 2012

• Bulletin of the Korean Chemical Society
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• v.25 no.1
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• pp.133-135
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• 2004

• YAKHAK HOEJI
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• v.55 no.5
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• pp.367-373
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• 2011

It was reported that the potency of TMMC derivatives was related to the presence of the 2'-hydroxy group on the A ring. Also, 4-dimethylamino group on the B ring lowered the anti-inflammatory potency of the chalcones. We synthesized various derivatives of 2'-hydroxy chalcones having other substituents on B ring. The synthetic derivatives showed the more potent anti-inflammatory effect, comparable to that of the TMMC derivatives reported previously.

• Bulletin of the Korean Chemical Society
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• v.16 no.1
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• pp.12-16
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• 1995

The diastereoselectivity of addition reaction of crotylmetal reagents to cobalt-complexed acetylenic aldehydes and metal-free aldehydes was examined. The anti-diastereomer was the predominant product when the crotyl metallics were Cr, Sn, and Zr. In THF, the uncomplexed aldehydes normally gave higher anti-diastereoselectivity. However, the cobalt-complex of silicon-substituted propynals with three bulky substituents produced increased proportions of syn-diastereomer. In DMF, the selectivity shifted towards syn-isomer except in the case of dimethylphenylsilyl substituent. When tributylstannane was used in the presence of BF3 etherate, moderate syn- selectivity was observed with uncomplexed aldehydes, but only decomposed products from complexed aldehydes.

• Bulletin of the Korean Chemical Society
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• v.17 no.6
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• pp.499-502
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• 1996

Two different acyl substituents were introduced at the lower rim of calix[4]arene by the two step reactions. Calix[4]arenes (1) reacted with 3,5-dinitrobenzoyl chloride to yield monosubstituted calix[4]arene (2). Second substitution was achieved by the reaction of 2 with various acyl chlorides. Aminomethylation of monobenzoylated calix[4]arene was conducted successfully in the presence of secondary amine and formaldehyde.

• Bulletin of the Korean Chemical Society
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• v.17 no.6
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• pp.525-528
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• 1996

Seven cali[4]arenes, having two different substituents in AAAB or AABB pattern at the upper rim of calix were synthesized by fragmentation condensation reaction of p-substituted phenol trimer (AAA) with 2,6-bishydroxymethylated 4-substituted phenol (B) or that of dimer (AA) with 2,2'-bishydroxymethylated dimer (BB). An equimolar mixture of the coupling components (trimer and monomer or dimer and dimer) was refluxed in dioxane in the presence of TiCl4to afford calix[4]arene 6 and 7 in 15-38% yield. The structure of calix[4]arenes was confirmed by elemental analysis and the 1H/13C NMR spectroscopy.

• Bulletin of the Korean Chemical Society
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• v.19 no.10
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• pp.1109-1112
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• 1998

An anchimeric assistance of anilide in the rearrangement of dichloro-1,4-oxathaines 1 to 2-chloromethyl dihydro-1,4-oxathiins 2 is described. The inductive effect of the carbonyl group of anilide was negligible in the rearrangement. A rate of the rearrangement depended on the basicity of anilide nitrogen. A hydrogen bonding between the anilide hydrogen and an oxygen atom of those substituents make the nitrogen less basic, resulting in the slower rearrangement.

• Bulletin of the Korean Chemical Society
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• v.11 no.6
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• pp.538-542
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• 1990

New aminothiazolyl cephalosporins with alkoxyiminomethyl(2-aminothiazol-4-yl)acetyl substituents at 7-position of cephems were synthesized starting from (2-aminothiazol-4-yl)acetate via one carbon homologation followed by acylation with 7-aminoceph-3-em-4-carboxylic acid derivatives. These new aminothiazolyl cephalosporins exhibit promising in vitro activities against various strains including Gram positive bacteria.

• Bulletin of the Korean Chemical Society
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• v.21 no.6
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• pp.618-622
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• 2000

The '3+1'type condensation of 16-thiatripyrromethane with $N-alkyl-24-bis[(\alpha+hydroxy-\alpha-phenyl)methyl]pvrole$, in the presence of acid catalyst afforded core-modified, N-confused porphyrins bearing alkyl groups at the rim nitrogen. The proton NMR spectra indicate that the bulkiness of the N-alkyl substituents is somewhat relatedwith the tiltedness of the inverted pyrrole ring. The changes in chemical shift of inner methine protons depending on the N-alkyl group and protonation site is discussed.

• Archives of Pharmacal Research
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• v.26 no.9
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• pp.667-678
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• 2003

We examined the effect of p-substituents in p-substituted cinnamyl methyl ethers and 1-(p-substituted phenyl)allyl methyl ethers with CSI, and confirmed that the CSI reaction of allyl ethers (p-substituted ethers) is a competitive reaction of $S_Ni{\;}and{\;}S_N1$ mechanism according to the stability of the carbocation. And, the only terminal allylic amine was obtained through the migration reaction in thermodynamic reaction condition.