• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1164-1166
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• 2009

Aromatic aldehydes are efficiently self-condensed into $\alpha$-hydroxy carbonyl compounds by polystyrene-supported ammonium cyanide as an excellent organocatalyst in C-C bond formation. The reaction proceeds in water under mild reaction conditions. The polymeric catalyst can be easily separated by filtration and reused several times without appreciable loss of activity.

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1380-1384
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• 2001

The chemoselective reactions of 1,n-dicarbonyl compounds with allyl halides using indium metal were investigated. $\alpha-Ketoesters$ such as ethyl pyruvate, ethyl 3-methyl-2-oxobutyrate and ethyl benzoylformate reacted with a variety of allyl halides i n the presence of indium to afford hydroxy unsaturated carbonyl compounds in good to excellent yields in MeOH/HCl at $25^{\circ}C.$ For the allyl bromide, the presence of various substituents at the $\alpha$ or $\gamma$ position exhibited little effects on both the reaction rates and yields. Ethyl acetoacetate or ethyl levulinate was treated with allylindium reagent to give hydroxy unsaturated carbonyl compounds in good yield. These results mean that both reactivity and selectivity are independent of the distance between carbonyl groups. 2,3-Butanedione or 1-phenyl-1,2-propanedione reacted with allylindium to produce monoallylation product as major compound.

• YAKHAK HOEJI
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• v.17 no.4
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• pp.223-234
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• 1973

Sixteen compounds of N-aroyl-N'-(4'-alkoxyphenyl) thiourea derivative, twenty one compounds of N-aeryl-N'(3'-hydroxy-4'-alkoxycar-bonylphenyl) thiourea derivative, three compounds of N-aeroyl-N'-.alpha.-naphthyiourea derivative and three compounds of N-cyanoacetyl-N'-aroyl thiosemicarbazide derivative were syntrhesized as potential antitubercular agent and were subjected to screening test for antitubercular activity against Mycobacterium turberculosis H/sub 37/Rv by tube dilution method in vitro. Of the fourty three eompounds, N-p-cyanobenzoyl-N'-(4'-iso-butoxyphenyl) thiourea, N-p-cyanobenzoyl-N'-(4-n-amoxyphenyl)thiourea, N-furoyl-N'-(3'-hydroxy-4'-ethoxycarbonylphenyl)thiourea, N-p-cyanobenzoyl-N'-(3'-hydroxy-4'-n-butoxycarbonylphenyl)thiourea, N-p-cyanobenzoyl-N'-(3'-hydroxy-4'-n-amoxycarbonylphenyl)thiourea, and N-5-nitrofuroyl-N'(3'-hydroxy-4"-n-amoxycarbonylphrnyl)thiourea showed the growth inhibition of M. tuberculosis H/sub 37/Rv at the coccentraction og 10.mu.g/ml, respectively.

• Natural Product Sciences
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• v.14 no.4
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• pp.249-253
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• 2008

Two oleanane-type triterpenes (1, 2) and their glycosides (4-6), and one ursane-type triterpene (3) have been isolated from a methanolic extract of Patrinia saniculaefolia Hemsley (Valerianaceae) through repeated silica gel and reversed-phase C-18 column chromatography. Their chemical structures were determined as oleanolic acid (1), oleanonic acid (2), 23-hydroxyursolic acid (3), 3-O-${\alpha}$-L-arabinopyranosyl-oleanolic acid (4), 3-O-${\beta}$-D-glucopyranosyl-oleanolic acid (5), and oleanolic acid 3-O-[${\alpha}$-D-xylopyranosyl-($1{\rightarrow}3$)-${\beta}$-D-glucuronopyranoside-6-O-butyl-ester] (6) on the basis of their MS, $^1H$-, and $^{13}C$-NMR spectral data. All compounds were isolated from the whole plant of the P. saniculaefolia for the first time. These compounds were examined for their anti-complement activity against the classical pathway of the complement system. Among them, compounds 1 - 3 exhibited anti-complement activity with $IC_{50}$ values of 470.1, 212.2, and 121.0 ${\mu}M$, respectively, whereas compounds 4 - 6 were inactive. These results suggest that the carbonyl or hydroxy group at C-3 in the oleananeand/or ursane-triterpenes are important for the anti-complement activity against the classical pathway.

• Journal of the Korean Chemical Society
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• v.21 no.2
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• pp.108-120
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• 1977

The approximate rates and stoichiometries of the reaction of lithium borohydride, with fifty two selected organic compounds containing representative functional groups under the standard condition (tetrahydrofuran, $0^{\circ}$), were studied.Among the active hydrogen compounds,primary alcohols and compounds containing an acidic proton liberated hydrogen relatively fast, but secondary and tertiary alcohols very sluggishly. All the carbonyl compounds examined were reduced rapidly within one hour. Especially, among the ${\alpha}{\beta}$-unsaturated carbonyl compounds tested, the aldehydes consumed one hydride cleanly, however the cyclic ketones consumed more than one hydride even at $-20^{\circ}$. Carboxylic acids were reduced very slowly, showing about 60% reduction in 6 days at $25^{\circ}$, however acyl chlorides reduced immediately within 30 minutes. On the other hand, the reductions of cyclic anhydrides proceeded moderately to the hydroxy acid stage, however the further reductions were very slow. Aromatic and aliphatic esters, with exception of the relatively moderate reduction of acetate, were reduced very slowly, however lactones were reduced at a moderate rate. Epoxides reacted slowly, but amides and nitriles as well as the nitro compounds were all inert to this reagent. And cyclohexanone oxime and phenyl isocyanate were reduced very sluggishly. Last of all, all sulfur compounds studied were inert to this hydride.