• Archives of Pharmacal Research
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• v.23 no.4
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• pp.315-323
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• 2000

Syntheses of new analogues of oxathiin carboxanilide (UC84) and their antiviral activities were described. The heterocyclic carboxylic acids including oxathiins (4), thiazines (9) and dithiins (13) in which the methyl was replaced either by lipophilic trifluoromethyl- or bulky phenylgroup were synthesized starting from $\beta$-keto esters (5). Reaction of 4, 9 and 13 with thionyl chloride followed by treatment of the substituted aniline 22 gave the corresponding carboxanilides (24a~24f). The carboxanilides were subjected to Laweson's reagent the corresponding thiocarboxanilides (24g~24k). The antiviral activities of the synthesized compounds against human immunodeficiency virus type 1 (HIV-1), poliovirus type 1 (PV-1 ), coxsackie B virus type 3 (CoxB-3), vesicular stomatitis virus (VSV) and herpes simplex virus type 1 (HSV-1) were presented. The antiviral activity against HIV-1 of dithiin carboxanilide (24e) was similar with that of UC84 (24a). The corresponding thiocarboxanilides (24g~24k) showed higher inhibitory activity against HIV-1 than the carboxanilides (24a, 24b, 24d, 24e). The compounds in which ether the lipophilic trifluorormethyl substituents (24d, 24f, 24i ,24k) or bulky phenyl substituent is present in the heterocyclic compounds showed lower inhibitory activity than that of the methyl substituents is present in the compounds against the HIV-1. But the trifluoromethylated dithiin (24f) showed higher inhibitory activity against PV-1 and CoxB-3 virus than commercial antiviral agents, ribavirin (RV).

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.723-728
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• 1998

The chemical behaviours of 4-methyl-2-oxo-2H-benzopyran-7-yl oxoacetyl hydrazine (2) towards some different reagents such as anhydride compounds, aromatic aldehydes, carb on disulphide, and nitrous acid yielded the corresponding pathalazine derivatives (3, 4, 5), hydrazone derivative (6), 1,3,4-oxadiazole derivative (7, 8, 9) and acid azide (10) respectively. Treatmen of 10 with absolute alcohols, amines and ethyl amino acid ester gave the corresponding carbamate derivative (11), substituted urea derivative (12) and ethyl substituted alkyl acetate (13) respectively. The biological activity of some synthesized compounds was evaluated.

• Preventive Nutrition and Food Science
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• v.2 no.4
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• pp.360-367
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• 1997

The chemistry background of the Maillard reaction focused on pyrazines and factors affecting the reaction products were reviewed. The Maillard reaction, also called a non-enzymatic browning reaction, is quite complex and generates numerous reaction products. In processed foods, it is generally accepted as a key reaction to produce flavor components. Specially, pyrazines possess an important impact character on the roasted foods with other heterocyclic compounds. The Maillard reaction is initiated by condensation between reducing sugar and amino group, and N-glycosylamines are produced via Schiff base with dehydration of water. After the rearrangement of the N-glycosylamines, they follow transformation into deoxyhexosones which are reactive intermediates. Degradation and fragmentation are facilitated by rearranged compounds. By condensation, pyrazine, one of the final Maillard products, is generated as a relatively stable form to provide specific aromas. During the processes of the reaction, chemical or physical environmental parameters affect the formation of the products.

• YAKHAK HOEJI
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• v.39 no.2
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• pp.118-130
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• 1995

Aliphatic & aromatic compounds with two nucleophilic functional groups which were chosen as nucleophiles reacted with 2,3-dichloro-1,4-naphthoquinone as a substrate to give cyclized products by nucleophilic vinyl substitution. And the trends in the syntheses of the heterocyclic compounds was studied and expounded. Besides, the biological activities of the products, especially activity as an agricultural chemical, were examined. Moreover 5-aminomethyl-2-pyrrolidinone was synthesized for the purpose of forming a polynuclear heterocyclic compound containing a similar structure of azasteroid. However only one chlorine of 2,3-dichloro-1,4-naphthoquinone was replaced by an amino group of pyrrolidinone and cyclization did not take place.

• Bulletin of the Korean Chemical Society
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• v.18 no.5
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• pp.484-488
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• 1997

The angular and planar heterocyclic compounds containing nitrogen, sulfur and oxygen were synthesized by reaction of 6,7-dichloro-5,8-quinoxalinedione with aromatic and aliphatic dinucleophiles. Nucleophilic reactivity was somewhat different between 2,3-dichloro-1,4-naphthoquinone and 6,7-dichloro-5,8-quinolinedione with dinucleophiles. The distribution of electron in heterocycle appeared to contribute to this difference. The intercalation comple of planar heterocyclic compound between GC/GC base pairs showed the optimum intercalation but the intercalation of angular heterocyclic compound was not good. Thus, the planar compound was expected to have antitumor activity.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7003-7006
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• 2015

Background: Nanoparticles of gold and silver are offering revolutionary changes in the field of cancer therapy. N-heterocyclic carbene (NHC) metal complexes possess diverse biological activities and are being investigated as potential chemotherapeutic agents. The purpose of this study was to examine the cytotoxicity and possible mechanisms of action of two types of newly synthesized nanofiber composites containing BIAN N-heterocyclic gold carbene complexes in two types of human cancer cells, namely breast cancer (MCF7) and liver cancer (HepG2) cells and also in normal human embryonic kidney cells (HEK 293). Materials and Methods: Cytotoxicity was assessed by MTT cell viability assay and oxidative stress by checking the total glutathione level. Results: Both compounds affected the cell survival of the tested cell lines at very low concentrations (IC50 values in the micro molar range) as compared to a well-known anti-cancer drug, 5 fluorouracil. A 60-80% depletion in total glutathione level was detected in treated cells. Conclusions: Reduction in total glutathione level is one of the biochemical pathways for the induction of oxidative stress which in turn could be a possible mechanism of action by which these compounds induce cytotoxicity in cancer cell lines. The in vitro toxicity towards cancer cells found here means that these molecules could be potential anticancer candidates.

• Bulletin of the Korean Chemical Society
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• v.23 no.5
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• pp.779-782
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• 2002

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.405-410
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• 1990

The aroma components of duchung tea and persimmon leaf tea were collected simultaneous distillation and extraction method. Those were analyzed and identified by GC-MS using a fused sillica capillary column. Seventy seven components, including 17 alcohols, 3 hydrocarbons, 15 ketones, 16 aldehydes, 8 esters,8 acids, 8 heterocyclic compounds and 2 phenols were confirmed in duchung tea. Seventy one components, including 17 alcohols, 10 hydrocabrons, 11 ketones, 13 aldehydes, 8 esters, 6 acids, 5 heterocyclic compounds and 1 phenol were confirmed in persimmon leaf tea. The most abundant components of duchung tea were aldehydes(23.31%) including 2-pentenal and heterocyclic compounds(16.71%) including $epoxy-{\beta}-ionone$. The most abundant components of persimmon leaf tea were alcohols(25.57%) including linalool and aldehydes(19.45%) including hexanal and hydrocarbons(10.40%) including ${\alpha}-copaene$.

• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.330-336
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• 2014

Purification of indole contained in model coal tar absorption oil was examined by extraction-distillation-crystallization combination. The absorption oil consists of nine components such as four kinds of nitrogen heterocyclic compounds (9.2% quinoline, 2.4% iso-quinoline, 4.7% indole, 2.4% quinaldine), three kinds of bicyclic aromatic compounds (14.2% 1-methylnaphthalene, 31.8% 2-methylnaphthalene, 23.5% dimethylnaphthalene), 5.5% biphenyl and 3.3% phenyl ether. 99.5% indole was recovered by combination of formamide extraction-distillation-solute crystallization using n-hexane. Furthermore, the recovery process of indole contained in coal tar absorption oil was studied by using the experimental results obtained by each operation of this work.

• Journal of Pharmacopuncture
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• v.24 no.1
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• pp.32-40
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• 2021

Objectives: Pathogenic microbes are causal agents for various types of severe and even lethal infectious diseases. Despite of development in medication, bacterial and fungal infections still persist to be a vital problem in health care. Bacteria and several fungal species have shown resistance to antibiotics used in treatment to current medications. Therefore, it is a considerable field of interest in the design and development of novel compounds with antimicrobial activity. Methods: The compounds bearing a heterocyclic ring play an imperative role among other organic compounds with pharmacological activity used as drugs in human for control and cure of various infections. Thiadiazoles containing nitrogen-sulfur atom as part of their cyclic structure which shown wide-ranging application as structural units of biologically active molecules and are very useful intermediates in Medicinal Chemistry. Results: The effectiveness of the thiadiazole nucleus was established by the drugs currently used for the treatment of various infections. 1,3,4-Thiadiazoles and some of their derivatives are widely studied because of their broad spectrum of pharmacological activities. Conclusion: In the present work, a series of 1,3,4-Thiadiazole derivatives were synthesized by cyclization of a group of various benzaldehyde with thiosemicarbazide in the presence of various reagent like FeCl3, HCHO by losing a molecule of water. These derivatives were found to possess prominent antimicrobial activity.