• Archives of Pharmacal Research
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• v.14 no.1
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• pp.12-18
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• 1991

The effect of urea and urea derivatives on the percutaneous absorption of salicylic acid and sodium salicylate through the skin of rabbit from petrolatum ointment was investigated. It was found that addition of urea or urea derivatives to the ointment base significantly increased the percutaneous absorption of the drugs in proportion to the concentratoin of the additive. The percutaneous absorptoin-enhancing activities of these compounds were that urea derivatives with the more and longer alkyl substituents showed the stronger activities. These activities of urea and urea derivatives were ascribed to the binding of these compounds with the lipids and proteins of the stratum corneum of the skin and the swelling of the tissues, which leads to the reduction of the barrier property of the layer. The preliminary skin irritation test showed that urea and urea derivatives were quite non-irritating to the skin. These results suggest that urea derivatives have a strong possibility to be developed as a percutaneous absorption enhancer.

• Applied Chemistry for Engineering
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• v.3 no.1
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• pp.100-110
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• 1992

Arylsulfonyl urea derivatives can be easily prepared in good yield by treating amines with arylsulfonyl carbamates in aqueous solution : 1) N-Arylsulfonyl-N'-aryl urea derivatives, 2) N-Arylsulfony-N'-alkyl urea derivatives, 3) N-Arylsulfonyl-N'- heterocyclic urea derivatives. The proposed reaction mechanisms for preparing arylsulfonyl ureas involve formation of an ion-pair conformation by initial acid-base reaction, then formation of a so-called tetrahedral intermediate by nucleophilic addition, followed by an acid-catalyzed elimination of an alkoxide ion and loss of a proton.

• Journal of the Korean Applied Science and Technology
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• v.26 no.1
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• pp.29-37
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• 2009

This study is focused on the synthesis of urea and amide derivatives particularly, since the amide moiety is an essential binding group at the binding site. Urea derivatives 3-7 and 13-14 were obtained by reaction of 2-aminopyrimidines and other amines with diverse isocyanates in pyridine as a solvent under reflux. The urea derivatives were obtained in low yield because of the highly electron deficient nature of the amino group of the 2-aminopyrimidine. Amide derivatives 8-10 were obtained in moderate yields by reaction of compound 1 with aryl chloride derivatives. Also, arylamine 11 was synthesized by Buchwald-Hartwig amination in moderate yields. Most of the compound did not show good activity against A375P melanoma cells, compared with Sorafenib as control compound.

• Archives of Pharmacal Research
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• v.15 no.2
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• pp.126-129
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• 1992

The critical micelle concentrations (CMCs) of aqueous solutions of a nonionic surfactant, polyoxyl 23 lauryl ether in the presence of various concentration of urea and its derivatives were measured. The CMC of the surfactant increase in proportion to the concentration of the additives, and the CMC-raising activities increased with more and longer alkyl grups substituted in urea. The CMC shift values were successfully correlated with the cloud point shift values and the protein-denaturing activities of the additives, respectively. These results suggest that the micelle formation, clouding of the surfactant and the protein denaturation are a closely related phenomenon, and a common mechanism is operating which might be the hydrophobic interaction.

• Applied Biological Chemistry
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• v.30 no.3
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• pp.227-233
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• 1987

Some derivatives of 3-(benzothiazol-2-yl)-1-methyl urea were synthesized by reaction of methyl isocyanate with 2-aminobenzothiazole derivatives prepared by thiocyanation of various substituted anilines. The compounds synthesized were identified by IR, NMR and mass spectra as 3-(5-methyl benzothiazol-2-yl)-1-methyl urea, 3-(5,6-dimethyl benzothiazol-2-yl)-1-methyl urea, 3-(6-ethyl benzothiazol-2-yl)-1-methyl urea, 3-(6-methoxy benzothiazol-2-yl)-1-methyl urea, 3-(6-chloro benzothiazol-2-yl)-1-methyl urea, and 3-(5, 6-dichloro benzothiazol-2-yl)-1-methyl urea. These compounds were subjected to the test for pre-emergence herbicidal activity in the pots with wettable powder formulation. All of these compounds showed pre-emergence herbicidal activity on the grasses (Digitaria adscendens HENR and Setaria viridis P. BEAUV) and broad-leaf weeds (Portulaca oleraces L. and Chenopodium album L.) at the dosage of 800g a.i. per 10a. Of the 6 compounds, 3-(6-ethyl benzothiazol-2-yl)-1-methyl urea showed the highest herbicidal effect on both the grasses and broad-leaf weeds. Even at the rate of 50g a.i. per 10a, this compound inhibited the growth of grasses, selectively.

• Bulletin of the Korean Chemical Society
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• v.19 no.1
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• pp.110-114
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• 1998

The hydrogen-bonding interactions between thioacetamide (TA) and urea derivatives such as tetramethylurea (TMU) and dimethyldiphenylurea (DMDPU) have been studied using near-infrared absorption spectroscopy. Thermodynamic parameters for the interactions between TA and urea derivatives were determined by analyzing the $v^{as}_{N-H}$+Amide Ⅱ combination band of TA at 1970 nm. The ΔH° values, indicating the intrinsic strength of hydrogen bonding, are - 23.0 kJ/mole and - 19.8 kJ/mol for TMU and DMDPU, respectively. This is well explained by the inductive effects of substituents. Ab initio molecular orbital calculations for the proton affinity of TMU, N,N-dimethylformamide (DMF), and N,N-dimethylacetamide (DMA) in gas phase have been carried out at HF/3-21G ad HF/6-31G(d) levels, showing that the proton affinity of TMU is larger than that of DMA, which agrees well the experimental results.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3857-3860
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• 2012

• Bulletin of the Korean Chemical Society
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• v.20 no.8
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• pp.953-956
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• 1999

• Archives of Pharmacal Research
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• v.15 no.1
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• pp.104-108
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• 1992

2, 3-Diphenyl-6-formyl-5-methoxyindole reacts with ethyl cyano acetate to yield the arylidene derivative which forms with urea and thiourea the corresponding pyrimidine derivatives. The arylidene derivatives react with hydrazines and with active methylenes to form the respective pyrazole derivatives and the $\alpha, \;\beta$-disubstituted acrylonitriles. Seven new compounds were tested for their effects on the arterial blood pressure of rats and analgesic activity.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.384-389
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• 2004

The purified ${\beta}-mannanase$ hydrolyzed various gums to mannose, ${\beta}-1,4-mannobiose$, $Gal^3Man_4$, and D.P 7 of galactosyl mannooligosaccharide, and isolated from the enzymatic hydrolysate for 24 hrs reaction by activated carbon column chromatography and Sephadex G-25 column chromatography. For the elucidate of antioxidant action of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ and DP 7 of galactosyl mannooligosaccharide and urea derivatives, coloration, reducing power, antioxidant activity and DPPH test were accomplished. The coloration was high at reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and urea. TLC of reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and ureas showed new reaction products, respectively. but except reaction mixture of ${\beta}-1,4-mannobiose$ and urea. The reducing power was high at reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and phenylthiourea. The reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and thiourea showed similar radical scavenging activities on DPPH to activity of AsA. The reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and thiourea, phenythiolurea shown strong antioxidative activites on the oxidation of linoneic acid.