• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3382-3388
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• 2011

Reaction of barbituric acid (BA), 1,3-dimethyl barbituric acid (DMBA) and 2-thiobarbituric acid (TBA) with cyanogen bromide and aldehydes in the presence of L-(+)-tartaric acid afforded a new route for the synthesis of stable heterocyclic 5-aryl-1H,1'H-spiro[furo[2,3-d]pyrimidine-6,5'-pyrimidine]2,2',4,4',6'(3H,3'H,5H)-pentaones which is a dimeric form of barbiturate (uracil and thiouracil derivative). In the reaction of 1,3-diethyl thiobarbituric acid (DETBA) the Knoevenagel condensation and then Michael adducts were obtained under the same condition. Structure elucidation is carried out by $^1H$ NMR, $^{13}C$ NMR, FT-IR and Mass analyses. Mechanism of the formation is discussed.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.31-32
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• 2011

• Journal of Pharmaceutical Investigation
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• v.1 no.1
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• pp.22-29
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• 1971

Barbituric acid 및 thiobarbituric acid 유도체와 beta-cyclodextrin과의 상호반응(相互反應)을 수용액(水溶液)과 유기용매중(有機溶媒中)에서 각(各) 약물(藥物)을 용해도(溶解度), 분자용(分子容), 열역학적(熱力學的)인 면(面)에서 분석(分析) 검계(檢計)하였다. 본실험(本實驗)에 사용한 약물(藥物)이 모두 용액(溶液)에서는 beta-cyclodextrin과 반응(反應)하여 용해도(溶解度)가 증가(增加)하였으며 고형(固型)의 침전을 형성(形成)하지는 않았으나 비교적(比較的) 안정(安定)한 회합(會合)이 이루어졌다. 본반응(本反應)의 기전(機轉)은 주(主)로 beta-cyclodextrin의 주요(主要)한 성질(性質)의 하나인 inclusion능(能)에 의(依)하여 이루어 졌음을 보고(報告)한다.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.8
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• pp.455-461
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• 2000

The inhibiting effects of electrical treeing and insulation properties of LDPE contained with treeing inhibitors was studied under radiation environment. Barbituric acid and its derivatives were selected as treeing inhibitors. The inception voltage and growth of tree, AC breakdown strength, volume resistivity, high frequency capacitance, and dissipation factor were observed as a function of dose(up to 1000 kGy). And also, measurements of thermo-luminescence(TL), and gel content were carried out. Crosslinked low density polyethylene(XLPE) contained with treeing inhibitors shows better insulation characteristics such as electrical tree propagation, AC breakdown strength, and volume resistivity than those of pure LDPE. The most effective treeing inhibitor was found on the barbituric acid contained XLPE.

• Journal of the Korean Chemical Society
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• v.46 no.2
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• pp.99-116
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• 2002

The thiazolylazo compounds and their Co(II), Ni(II) and Cu(II) complexes of barbituric acid, uracil, thiouracil, citrazinic acid, chromotropic acid, gallic acid, pyrogallol and salicylic acid were pre-pared and characterized by $^1H$ NMR , IR and the effect of pH on the electronic absorption spectra . The mode of ionization, the electronic transitions and the dissociation constants were discussed. The stoichiometries of the complexes were of 1:1, 2:1 and 3:2 (M:L). The copper complexes are of isotropic ESR spectra (except that of gallic acid which showed a complicated one) and are of magnetically diluted behaviour with orbital con-tribution. Detailed DTA data were obtained and discussed.

• Bulletin of the Korean Chemical Society
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• v.31 no.2
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• pp.339-343
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• 2010

A series of $Ce_1Mg_xZr_{1-x}O_2$ (CMZO) mixed metal oxide with different molar ratio were prepared by simple co-precipitation method. The prepared materials were tested for their catalytic activity performance using Knoevenagel condensation of various aromatic aldehydes with barbituric acid under solvent-free condition in microwave. The best catalytic activity was obtained with CMZO (1:0.6:0.4). The synthesized materials were characterized by using XRD, FT-IR, SEM-EDS techniques.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.6
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• pp.829-834
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• 2015

A simple and sensitive hydrogel-based detecting gel has been presented for the qualitative determination of cyanogen chloride(CK) using Konig reaction. To optimize Konig reaction conditions, the effects of pyridine and barbituric acid concentration were investigated. Under the optimized conditions, CK gas concentration was directly related with absorbance change at 567 nm. Based on aqueous solution test results, we finally prepared CK detecting hydrogel by absorbing pyridine and barbituric acid solution. Color change of the prepared CK detecting hydrogel was clearly observed when the detecting gel was exposed to 10 ppm CK gas.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.926-928
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• 1999

Treeing inhibitors of barbituric acid derivatives effects on the electrical properties of crosslinked low density polyethylene under radiation environments were investigated. The electrical parameters for tree inception voltage, AC breakdown strength, volume resistivity, capacitance and dissipation factor at 1MHz and thermoluminescence, gel content measurements were discussed as a function of irradiated dosages. From the results, barbituric acid among the treeing inhibitors was shown the best treeing and radiation resistance.

• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.940-951
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• 2011

Reaction of 1-methylpyrimidine-(1H,3H,5H)-2,4,6-trione (1-MBA 1) as an unsymmetrical barbituric acid with cyanogen bromide and various aldehydes in the presence of triethylamine and/or pyridine afforded diastereomeric mixtures of new class of heterocyclic stable 5-aryl-1,1'-dimethyl- and 5-aryl-3,1'-dimethyl-1H,1'H-spiro[furo[2,3-d]pyrimidine-6,5'-pyrimidine]2,2',4,4',6'(3H,3'H,5H)-pentaones which are dimeric forms of 1-methyl barbiturate at the range of $0^{\circ}C$ to room temperature. In the reaction of some aldehydes with 1-MBA and BrCN were afforded a mixture of diastereomers. Another two aldehydes such as 4-cyano- and 2-hydroxybenzaldehydes gave exclusively two diastereomers in which binded to the salt of triethylammonium hydrobromide by intermolecular H-bond in ratio of 1:1. 4-Hydroxybenzaldehyde and 2-pyridinecarbaldehyde gave exclusively one diastereomer under the same condition. Aldehydes possessing strong electron-donor were produced exclusively two geometric isomers of Knoevenagel adduct (E- and Z-isomers). The structures of compounds were deduced by $^1H$ NMR, $^{13}C$ NMR and FT-IR spectroscopy. Mechanism of the formation is discussed.

• Journal of the Korean Society of Tobacco Science
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• v.2 no.2
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• pp.14-19
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• 1980

The spectrophotometric determination of nictotine content with barbituric acid buffer solution was carry out. Absorption maximum for the proposed solution appeared at 505 nm and the absorbance remained stable for 15 minute at pH 4.2. Lambert-Beer law was proved to be applicable in the range of nicotine concentration of $7.5\mu{g}/ml$~$25\mu{g}/ml$. According to the analysis of nicotine contents in Burley and Flue-cured tobacco leaves by this method, the relative deviation was obtained to be 2.8% in comparision with the Griffith method.