• Analytical Science and Technology
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• v.26 no.4
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• pp.256-261
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• 2013

The efficiency of the two extractions (refluxing extraction and heating-block extraction) was compared to develop the simple analytical method for the determination of capsaicinoids, including capsaicin and dihydrocapsaicin in red pepper powder. For the method development, the parameters, including particle size, extraction time and sample size, were evaluated using ultra high performance liquid chromatography (u-HPLC). It was found that the most effective extraction time of the refluxing extraction was 3 hr. The higher extraction efficiency was obtained with the fine particle of a mild red pepper powder, while the particle size did not affect the extraction efficiency in case of the hot red pepper powder. The higher extraction efficiency was obtained with the small size of sample taken because of the ratio of the large extracting solvent to sample amount. The extraction efficiency of the refluxing method was 3-9% higher than that of the heating-block method, however, the heating-block method could be applied to the determination of capsaicinoids in the red pepper powder for the purpose of quality control of the product.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2260-2266
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• 2011

4-Chlorotetrazolo[1,5-a]quinoxaline (III) was synthesized by azide (2+3) cycloaddition of 2,3-dichloroquinoxaline (II). Compound (III) on further refluxing with hydrazine hydrate furnished 4-hydrazinotetrazolo[1,5-a]quinoxaline (IV). Further refluxing of (IV) with different aromatic aldehydes in methanol yielded corresponding Schiff's bases V(a-j). Various 4-aminotetrazolo[1,5-a]quinoxaline based azetidinones VII(a-j) were synthesized by stirring the compounds V(a-j), at low temperature, with equimolar mixture of chloroacetylchloride & triethylamine in dry benzene, while 4-aminotetrazolo[1,5-a]quinoxaline based thiazolidinones VIII(a-j) were synthesized by refluxing Schiff's bases V(a-j) with thioglycolic acid in oil-bath. The structures of all the compounds were confirmed on the basis of $^1H$-NMR & FT-IR spectral data. All the newly synthesized compounds were screened for in-vitro antimicrobial activity against E. coli, S. aureus, K. pneumoniae & P. aeruginosa & antifungal activity against C. albicans. Few of them have exhibited the promising activity.

• Childhood Kidney Diseases
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• v.18 no.1
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• pp.29-35
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• 2014

Introduction: Persistent vesicoureteral reflux (VUR), a major cause of urinary tract infection (UTI) in children, can result in serious renal complications, such as reflux nephropathy and chronic renal failure. We evaluated the clinical characteristics and prognostic factors of VUR. Methods: From December 1993 to May 2011, we examined 117 children with vesicoureteral reflux who were admitted to the Department of Pediatrics and Urology, Chungbuk National University hospital for a UTI. The patients were managed medically or surgically. Results: Male patients had a slightly higher prevalence of VUR than female patients (55%). The degrees of the 161 refluxing ureters, as classified by the International Reflux Study Committee, were as follows: grade I, 15 ureters; grade II, 32 ureters; grade III, 54 ureters; grade IV, 26 ureters; grade V, 34 ureters. One hundred and sixty-one renal units (115 cases) underwent a 99m TC-DMSA renal scan, and 62% showed abnormal findings. The incidence of renal cortical defects showed a direct correlation with the severity of VUR. Ninety-four refluxing ureters were followed up medically, and 66 ureters (67%) either disappeared or improved. However, 9 refluxing ureters persisted. The spontaneous resolution rate of VUR seemed to be higher in younger patients with lower grades of reflux, and without renal cortical defects. Sixty-seven refluxing ureters (41%) were treated surgically, 62 refluxing ureters (92%) disappeared, and 5 refluxing ureters (8%) persisted. Conclusion: The incidence of renal cortical defects in patients with UTIs was 62% (in a 99m TC-DMSA renal scan), and showed a direct correlation with the severity of VUR. The spontaneous resolution rate seemed to be lower in the patients with higher grades of VUR, older age (over 4 years old) and diffuse renal cortical defects.

• YAKHAK HOEJI
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• v.9 no.1_2
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• pp.1-3
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• 1965

A new compound, (5-nitro-2-furfurylidene)-p, $p^{'}$ -diaminodiphenylsulfone, was synthesized by refluxing the mixture of 5-nitrofurfural and p, $p^{'}$-diaminodiphenylsulfone$ in ethanol solution. It exhibited good antibactericidal action against several micro-organisms.

• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.58-61
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• 1957

The organic titanium compounds, $Ti(OR)_4\;and\;Cl_2Ti(OR)_2$ were prepared by adding theoretical amounts of $TiCl_4$ to ROH in the medium of $CCl_4$. Among the compounds of the above two types, the former $Ti(OR)_4$was polymerized by refluxing them with R·OH and water at ordinary temperature and the latter, $Cl_2Ti(OR)_2$, by adding water to them.

• Bulletin of the Korean Chemical Society
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• v.24 no.3
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• pp.295-298
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• 2003

α,β-Unsaturated aldehydes and ketones are regioselectively reduced to the corresponding allylic alcohols with /Dowex1-x8 system in THF at room temperature. This system is also efficient for the conversion of α-diketones and acyloins to the vicinal diols in refluxing THF.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.362.2-362.2
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• 2002

Antofine belongs to the Phenathroindolizidine group of alkaloids. This natural products exhibit interesting biological properties such as antitumour activity. and anti-inflammentory. Wittig reaction of phenathrenealdehyde with the phosponium salt provided the phenathreneazidealkene in good yield. Intramolecular 1.3-dipolar cycloaddition of the resulting azidealkent in refluxing benzene proceeded the imine. It was reduced with cyanoborohydride of Noyori's Asymmetric Hydrogenation. (omitted)

• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1181-1187
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• 2003

Condensation of 4-cyano-5,6-dimethyl-3-pyridazinone 1 with aromatic aldehydes gave the novel styryl derivatives 2a-c. Refluxing of compound 2a with phosphorus oxychloride furnished 3-chloropyridazine derivative 3. Compound 3 was reacted with thiourea and produced pyridazine-3(2H)thione 4. Thieno[2,3-c]- pyridazines 5a-e were achieved by cycloalkylation of compound 4 with halocompounds in methanol under reflux and in the presence of sodium methoxide. Also, refluxing of compound 4 with N-substituted chloroacetamide in the presence of potassium carbonate afforded thienopyridazines 6a-e. Cyclization of compound 6 with some electrophilic reagents as carbon disulfide and triethyl orthoformate furnished the novel pyrimido[4',5':4,5]thieno[2,3-c]pyridazines 12 and 13a-c, respectively. Diazotisation of compound 6 with sodium nitrite in acetic acid produced the pyridazino[4',3':4,5]thieno[3,2-d][1,2,3]triazines 14a-c. Ternary condensation of compound 1, aromatic aldehydes and malononitrile in ethanol containing piperidine under reflux afforded the novel phthalazines 16a-c. Compound 3 was subjected to some nucleophilic substitution reactions with amines and sodium azide and formed the aminopyridazines 17a, b and tetrazolo[1,5-b]-pyridazine 19, respectively. The structures of the synthesized compounds were established by elemental and spectral analyses.

• Analytical Science and Technology
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• v.8 no.3
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• pp.281-284
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• 1995

The effect of permanganate concentration and refluxing time on the test COD results were investigated, as a validation test of the revised procedure. The amended protocol involves the use of a more dilute(1/2.5) permanganate solution(0.010N) and a shorter(1/3) refluxing period(20 min). This revision resulted only 70% of the COD value determined by the old procedure with 8 somewhat improved precision(CV 4.6%${\rightarrow}$3.3%). The dominant factor that influences the decrease in the COD result is the oxidant concentration, being two thirds of the overall effect. The same results were obtained in the comparison test using seawater samples.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.3943-3949
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• 2012

A series of aromatic hydrazides 3a-j were prepared by refluxing esters 2a-j with hydrazine hydrate in methanol, which were prepared by the esterification of 1a-j. Acetohydrazides 3a-j upon treatment with carbon disulfide and methanolic potassium hydroxide yielded potassium dithiocarbazate salts 4a-j, which on refluxing with hydrazine hydrate yielded substituted 4-amino-5-aryl-3H-1,2,4-triazole-3-thiones 5a-j. The target compounds 6a-j were synthesized by condensing furan-3-carboxylic acid in the presence of polyphosphoric acid under reflux. The structures of newly synthesized compounds were characterized by IR, $^1H$ NMR, $^{13}C$ NMR, elemental analysis and mass spectrometric studies. All the synthesized compounds were screened for their urease, acetylcholine esterase inhibition, antioxidant and alkaline phosphatase inhibition activity. Almost all of the compounds 6a-j showed good to excellent activities against urease and acetylcholine esterase more than the reference drugs. Compounds 6f and 6g were more potent scavenger of free radicals than the reference n-propyl gallate. Compound 6b and 6h showed excellent activities of alkaline phosphatase as compare to the reference $KH_2PO_4$.