• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제2권1호
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• pp.85-90
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• 1998

The reaction rate of $CO_2$ with 2-amino-2-methyl-1-propanol (AMP), MEA monoethanolamine(MEA) and diethanolamine (DEA) in aqueous solutions has been determined using a stirred vessel with a plane gas-liquid interface over a wide range of concentrations of amines at different temperatures. The results show that the overall reaction rate is first order with respect to both $CO_2$ and amine. The reaction rate constant varies with temperature according to the relationship which agrees with the experimental data. The proposed interpretation is that the kinetic rate determining step is a reaction of $CO_2$ with amine to form carbamic acid which is then totally and immediately ionized.

• 한국환경과학회지
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• 제2권1호
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• pp.85-90
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• 1993

The reaction rate of $CO_2$ with 2-amino-2-methyl-1-propanol (AMP), MEA monoethanolamine (MEA) and diethanolamine (DEA) in aqueous solutions has been determined using a stirred vessel with a plane gas-liquid interface over a wide range of concentrations of amines at different temperatures. The results show that the overall reaction rate is first order with respect to both $CO_2$ and amino. The reaction rate constant varies with temperature according to the relationship which agrees with the experimental data. The proposed interpretation is that the kinetic rate determining step is a reaction of $CO_2$ with amine to form carbamic acid which is then totally and immediately ionized.

• 한국인쇄학회지
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• 제1권1호
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• pp.57-60
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• 1983

Among the gelatin hardness for photographic emulaion, the formaldehyde, dialdehydes, n-Methylol compounds, ketones, carbonylic acid and carbamic acid derivatives, and s-Triazine derivatives were studied The greater purts of hardeners formed cross-link by the reaction with E-Amino group in the lysine and OH group in the hydroxylysine. Glutaraldehyde produced most stable cross-link due to the formation of pyridinum ion. 2.5- hexanedione and 3-hexene-2,5-dione possible to use as the ketone hardner. The sodium salt of 2.4-dichloro-6-hydroxy-S-Triazine was newly developed as the olefinic hardners for emulsion.

• 한국인쇄학회지
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• 제1권1호
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• pp.69-75
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• 1983

사전유제용 gelatin경화제 중에서 Formai-dehyde, dai;dehyde, n-Methylol 화합물, Ketone, 카르복실산 및 카바밀산과 그 유도체, a-Trizine 경화제에 관하여 고찰하였다. 대부분의 경화제가 gelatin에 있는 -OH기와의 반응으로 가교결합이 생성되며 amino산의 카르복실산과 amido결합으로 가교결합을 이룬다. Glutaraldehyde는 안정성이 뛰어난 Pyridinium을 생성하였으며 Ketone은 2.5-He-xadione이나 3-Hexena-2.5dione이 사용되며 s-Triazine의 Olefinic 경화제는 2.4-dichloro-6-hydroxy-S-Triazine의 나트륨염이 유제경화용으로 사용된다.

• Archives of Pharmacal Research
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• 제24권6호
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• pp.503-507
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• 2001

trans-Metanicotine, a subtype (${\alpha}_4{\beta}_2$)-selective ligand for neuronal nicotinic acetylcholine receptor, is under clinical phase for Alzheimer's disease. An efficient synthetic route for ($\pm$)-methyl-(1-aryl-4-pyridin-3-yl-but-3-enyl)-am ices, derivatives of tracts-metanicotine, was explored. Allylation reaction of aryl aldimines with allylmagnesium bromide in THF gave ($\pm$)-methyl-(1-aryl-but-3-enyl)-amines. Protection of the amines with the Boc group and following Heck reaction of the N-Boc amines with 3-bromopyridine gave ($\pm$)-methyl-(1-aryl-4-pyridin-3-yl-but-3-enyl)-carbamic acid tert-butyl esters. Deprotection of the N-Boc group in aqueous 1 N-HCI solution gave the titled amines in good yields. Thus, trans-metanicotine analogues modified at the ${\alpha}-position$ of the methylamino group with amyl groups were obtained in 5 steps.

• 분석과학
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• 제35권5호
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• pp.197-204
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• 2022

A gas chromatography-mass spectrometric method was developed for determining 5-chloro-2-methyl-4-isothiazolin-3-one (CMIT), 2-methyl-4-isothiazolin-3-one (MIT), 1,2-benzisothiazolin-3-one (BIT), 3-iodo-2-propynyl butyl carbamic acid (IPBC) and benzoic acid (BA) in household products. A 0.5 g sample was placed in a test tube and dissolved with 5 mL water, 5 mL methylene chloride and 1.0 mL methanol. The solution was extracted by ultra-sonication followed by mechanical shaking using the salting out effect. Under the established condition, the lowest quantification limits of all analytes were in the range of 0.04-10 mg/kg and their relative standard deviations were less than 8.0 %. The method was used to analyze 10 household products. As a result of analyzing 10 household products, MIT was detected in the range of 1.2-3.5 mg/kg in 3 of 10 samples, CMIT was detected in the range of 2.6-8.2 mg/kg in 3 of 10 samples, and BA was detected in the range of 5.0-15 mg/kg in 4 of 10 samples. Meanwhile, BIT and IPBC were not detected in any of the products. It has been shown that this method can be used for the simultaneous determination of biocides with various physical and chemical properties in household products.

• Journal of Microbiology and Biotechnology
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• 제34권7호
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• pp.1452-1463
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• 2024

Fungi generate different metabolites some of which are intrinsically bioactive and could therefore serve as templates for drug development. In the current study, six endophytic fungi namely Aspergillus flavus, Aspergillus tubigenesis, Aspergillus oryzae, Penicillium oxalicum, Aspergillus niger, and Aspergillus brasiliensis were isolated and identified from the medicinal plant, Silybum marianum. These endophytic fungi were identified through intra transcribed sequence (ITS) gene sequencing. The bioactive potentials of fungal extracts were investigated using several bioassays such as antibacterial activity by well-diffusion, MIC, MBC, anti-biofilm, antioxidant, and haemolysis. The Pseudomonas aeruginosa PAO1 was used to determine the antibiofilm activity. The ethyl acetate extract of Aspergillus flavus showed strong to moderate efficacy against Staphylococcus aureus, Escherichia coli, P. aeruginosa, and Bacillus spizizenii. Aspergillus flavus and Aspergillus brasiliensis exhibited significant antibiofilm activity with IC₅₀ at 4.02 and 3.63 mg/ml, while A. flavus exhibited maximum antioxidant activity of 50.8%. Based on HPLC, LC-MS, and NMR experiments kojic acid (1) and carbamic acid (methylene-4, 1-phenylene) bis-dimethyl ester (2) were identified from A. flavus. Kojic acid exhibited DPPH free radical scavenging activity with an IC₅₀ value of 99.3 ㎍/ml and moderate activity against ovarian teratocarcinoma (CH1), colon carcinoma (SW480), and non-small cell lung cancer (A549) cell lines. These findings suggest that endophytic fungi are able to produce promising bioactive compounds which deserve further investigation.

• 대한임상독성학회지
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• 제5권1호
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• pp.74-78
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• 2007

The carbamates are a group of insecticides derived from carbamic acid, with a broad spectrum of uses as agricultural and household garden insecticides. Carbamate insecticides are reversible cholinesterase inhibitors. Their inhibitory action is mediated by reversible carbamylation of acetylcholine, as with the organophosphate insecticides. Carbamates are absorbed by the body through multiple routes, including inhalation, ingestion, and dermal absorption. Although poisoning can result from occupational exposure or accidental ingestion, in most cases there is suicidal intent. This is particularly true in developing countries, where the highest incidence of morbidity and mortality from this cause occurs. Cardiac complications often accompany poisoning by carbamate compounds, which may be serious and often fatal. The extent, frequency, and pathogenesis of cardiac toxicity from carbamate compounds has not been clearly defined. Possible mechanismsinclude sympathetic and parasymphatetic overactivity, hypoxemia, acidosis, electrolyte derangements, and a direct toxic effect of the compounds on the myocardium. Patients with carbamate poisoning should immediately be transferred to an intensive or coronary care unit where appropriate monitoring and resuscitative facilities are available. We here report a case of acute coronary syndrome resulting from acute carbamate ingestionthat resulted in a healthy discharge.

• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2325-2332
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• 2012

A series $[C_3Omim]$[X] of imidazolium cation-based ILs, with ether functional group on the alkyl side-chain have been synthesized and structure of the materials were confirmed by various techniques like $^1H$, $^{13}C$ NMR spectroscopy, MS-ESI, FTIR spectroscopy and EA. More specifically, the influence of changing the anion with same cation is carried out. The absorption capacity of $CO_2$ for ILs were evaluated at 30 and $50^{\circ}C$ at ambient pressure (0-1.6 bar). Ether functionalized ILs shows significantly high absorption capacity for $CO_2$. In general, the $CO_2$ absorption capacity of ILs increased with a rise in pressure and decreased when temperature was raised. The obtained results showed that absorption capacity reached about 0.9 mol $CO_2$ per mol of IL at $30^{\circ}C$. The most probable mechanism of interaction of $CO_2$ with ILs were investigated using FTIR spectroscopy, $^{13}C$ NMR spectroscopy and result shows that the absorption of $CO_2$ in ether functionalized ILs is a chemical process. The $CO_2$ absorption results and detailed study indicates the predominance of 1:1 mechanism, where the $CO_2$ reacts with one IL to form a carbamic acid. The $CO_2$ absorption capacity of ILs for different anions follows the trend: $BF_4$ < DCA < $PF_6$ < TfO < $Tf_2N$. Moreover, the as-synthesized ILs is selective, thermally stable, long life operational and can be recycled at a temperature of $70^{\circ}C$ or under vacuum and can be used repeatedly.

• The Korean Journal of Physiology and Pharmacology
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• 제13권2호
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• pp.71-78
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• 2009

(S)-Carbamic acid 2-[4-(4-fluoro-benzoyl)-piperidin-1-yl]-1-phenyl-ethyl ester hydrochloride (YKP1447) is a novel "atypical" antipsychotic drug which selectively binds to serotonin (5-$HT_{2A}$, Ki=0.61 nM, 5-$HT_{2C}$, Ki=20.7 nM) and dopamine ($D_2$, Ki=45.9 nM, $D_3$, Ki=42.1 nM) receptors with over $10\sim100$-fold selectivity over the various receptors which exist in the brain. In the behavioral studies using mice, YKP1447 antagonized the apomorphine-induced cage climbing ($ED_{50}$=0.93 mg/kg) and DOI-induced head twitch ($ED_{50}$=0.18 mg/kg) behavior. In the dextroamphetamine-induced hyperactivity and conditioned avoidance response (CAR) paradigm in rats, YKP1447 inhibited the hyperactivity induced by amphetamine ($ED_{50}$=0.54 mg/kg) and the avoidance response ($ED_{50}$=0.48 mg/kg); however, unlike other antipsychotic drugs, catalepsy was observed only at much higher dose ($ED_{50}$=68.6 mg/kg). Based on the CAR and catalepsy results, the therapeutic index (TI) value for YKP1447 is over 100 (i.p.). These results indicate that YKP1447 has an atypical profile and less undesirable side effects than currently available drugs.