http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Voltammetric Studies on Some Thiadiazoles and Their Derivatives
A.A.El Maghraby 한국전기화학회 2009 한국전기화학회지 Vol.12 No.1
The redox characteristics of 2-arylaldehydehydrazono-3-phenyl-5-substituted-2,3-dihydro- 1,3,4-thiadiazoles (1a-h) have been investigated in nonaqueous solvents such as 1,2-dichloroethane (DCE), dichloromethane (DCM), acetonitrile (AN), Tetrahydrofuran (THF), and dimethylsulfoxide (DMSO) at platinum electrode. Through controlled potential electrolysis, the oxidation and reduction products of the investigated compounds had been separated and indentified. The redox mechanism had been suggested and proved. It had been found that all the investigated compounds were oxidized in two irreversible one-electron processes following the well-known pattern of The EC-mechanism; the first electron loss gives the corresponding cation- radical which is followed by proton removal from the ortho-position in the N-phenyl ring forming the radical. The obtained radical undergoes a second electron uptake from the nitrogen in the N = C group forming the unstable intermediate (di-radical cation) which undergoes ring closure forming the corresponding cation. The formed cation was stabilized in solution through its combination with a perchlorate anion from the medium. On the other hand, these compounds are reduced in a single two-electron process or in a successive two one-electron processes following the well known pattern of the EEC-mechanism according to the nature of the substituent; the first one gives the anion-radical followed by a second electron reduction to give the dianion which is basic enough to abstract protons from the media to saturate the (C = O) bond.
Saleem, Muhammad,Rafiq, Muhammad,Hanif, Muhammad,Rama, Nasim Hasan,Seo, Sung-Yum,Lee, Ki-Hwan Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.8
A new series of 2,5-disubstituted-1,3,4-thiadiazoles 6a-i was synthesized by overnight stirring various 1,4-disubstituted thiosemicarbazides 5a-i in polyphosphoric acid followed by neutralization. The structures of newly synthesized compounds 5a-i and 6a-i were characterized by IR, $^1H$ and $^{13}C$ NMR, elemental analysis and mass spectrometric studies. All the synthesized compounds were evaluated for their urease and acetylcholine esterase inhibition activities. Thiosemicarbazides 5a-i are found to possess excellent potential for urease inhibition, more than the standard drug. Thiosemicarbazides 5a-i are more potent urease inhibitor than their cyclic analogues thiadiazoles 6a-i. Almost all of the compounds are excellent inhibitors of acetylcholine esterase. The inhibition of acetylcholine esterase of compounds 5a, 5c, 5d, 5g, 5i, 6e, 6f, 6g, and 6i is much more than that of standard drug.
Muhammad Saleem,Muhammad Rafiq,Muhammad Hanif,Nasim Hasan Rama,Sung-Yum Seo,Ki-Hwan Lee 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.8
A new series of 2,5-disubstituted-1,3,4-thiadiazoles 6a-i was synthesized by overnight stirring various 1,4- disubstituted thiosemicarbazides 5a-i in polyphosphoric acid followed by neutralization. The structures of newly synthesized compounds 5a-i and 6a-i were characterized by IR, 1H and 13C NMR, elemental analysis and mass spectrometric studies. All the synthesized compounds were evaluated for their urease and acetylcholine esterase inhibition activities. Thiosemicarbazides 5a-i are found to possess excellent potential for urease inhibition, more than the standard drug. Thiosemicarbazides 5a-i are more potent urease inhibitor than their cyclic analogues thiadiazoles 6a-i. Almost all of the compounds are excellent inhibitors of acetylcholine esterase. The inhibition of acetylcholine esterase of compounds 5a, 5c, 5d, 5g, 5i, 6e, 6f, 6g, and 6i is much more than that of standard drug.
A One-Step Synthesis and Antimicrobial Activities of New Substituted Dihydro-1,3,4-Thiadiazoles
Asma M. Mahran,Nasser A. Hassan 대한약학회 2006 Archives of Pharmacal Research Vol.29 No.1
In this study, 2-N-arylimino-2,3-dihydro-1,3,4-thiadiazoles derivatives (6a-h) were synthetized. The mechanism of the studied reactions was discussed. The chemical structures of the compounds were elucidated by their IR, 1H-NMR, 13C-NMR, and Mass spectral data and elemental analyses. The compounds were tested for antimicrobial activity using diffusion agar technique.
Shakya, Ashok K.,Mishra, Pradeep,Patnaik, G.K.,Shukla, Rakesh,Srimal, R.C. The Pharmaceutical Society of Korea 1998 Archives of Pharmacal Research Vol.21 No.6
Sixteen novel 2-substituted acetyl amino-5-alkyl-1,3,4-thiadiazol were synthesized and screened for their pharmacological activities. A few of the compounds namely 11, 12 and 16 showed anti-inflammatory activities comparable to phenylbutazone. Compound 12 also showed significan non-specific spasmolytic activity. Diuretic activity of compound 15 at a dose level of 90mg/kg p.o. was two fold higher compared to 50mg/kg p.o. of furosemide. Comparable diuresis was aso produced by compounds 9, 10, and 16.
Voltammetric Studies on Some Thiadiazoles and Their Derivatives
Maghraby, A. A. El,Abou-Elenien, G. M.,Rateb, N. M,Abdel-Tawab, H. R. The Korean Electrochemical Society 2009 한국전기화학회지 Vol.12 No.1
The redox characteristics of 2-arylaldehydehydrazono-3-phenyl-5-substituted-2, 3-dihydro-1, 3, 4-thiadiazoles (1a-h) have been investigated in nonaqueous solvents such as 1, 2-dichloroethane (DCE), dichloromethane (DCM), acetonitrile (AN), Tetrahydrofuran (THF), and dimethylsulfoxide (DMSO) at platinum electrode. Through controlled potential electrolysis, the oxidation and reduction products of the investigated compounds had been separated and indentified. The redox mechanism had been suggested and proved. It had been found that all the investigated compounds were oxidized in two irreversible one-electron processes following the well-known pattern of The EC-mechanism; the first electron loss gives the corresponding cation-radical which is followed by proton removal from the ortho-position in the N-phenyl ring forming the radical. The obtained radical undergoes a second electron uptake from the nitrogen in the N = C group forming the unstable intermediate (di-radical cation) which undergoes ring closure forming the corresponding cation. The formed cation was stabilized in solution through its combination with a perchlorate anion from the medium. On the other hand, these compounds are reduced in a single two-electron process or in a successive two one-electron processes following the well known pattern of the EEC-mechanism according to the nature of the substituent; the first one gives the anion-radical followed by a second electron reduction to give the dianion which is basic enough to abstract protons from the media to saturate the (C = O) bond.
Mohamed Ahmad E.,Elgammal Walid E.,Dawaba Aya M.,Ibrahim Ahmed G.,Fouda Amr,Hassan Saber M. 한국응용생명화학회 2022 Applied Biological Chemistry (Appl Biol Chem) Vol.65 No.4
Herein, two new polymers designated as Cs-EATT and Cs-BATT have been synthesized via linking the chitosan with the synthesized 1,3,4-thiadiazole compounds. They were characterized using 1 H, 13 C-NMR, FT-IR, TGA, Elemental analysis, Mass spectrum, and UV–vis spectrophotometer. The synthesized polymers exhibit high activity to control the growth of pathogenic bacteria ( S. aureus , B. subtilis , E. coli, and P. aeruginosa ), and unicellular fungi ( C. albicans ). The MIC values were in the range of 25–100 µg mL –1 for Cs-EATT and 25–200 µg mL –1 for Cs-BATT with varied clear zones. The new polymers were mixed with three film-forming agents: polyvinyl alcohol, hydroxyethyl cellulose, and carboxymethyl cellulose to form six film dressings designated as E1, E2, and E3 for Cs-EATT, and B1, B2, and B3 for Cs-BATT, respectively. The evaluation of film dressings showed that the formed films had transparency, uniformity, homogeneity, elasticity, and non-irritation pH values for skin within the normal range. The maximum percentages of Cs-E/B-ATT content were recorded for film dressings E2 and B2, with values of 92.5% and 94.9%, respectively. Also, the release percentages varied according to film dressing formulation, with values in the ranges of 83.88–93.2% for Cs-EATT and (87.7–97.35%) for Cs-EATT after 9 h.
A One-Step Synthesis and Antimicrobial Activities of New Substituted Dihydro-1,3,4-Thiadiazoles
Mahran, Asma M.,Hassan, Nasser A. The Pharmaceutical Society of Korea 2006 Archives of Pharmacal Research Vol.29 No.1
In this study, 2-N-arylimino-2,3-dihydro-1,3,4-thiadiazoles derivatives (6a-h) were synthetized. The mechanism of the studied reactions was discussed. The chemical structures of the compounds were elucidated by their IR, $^1H-NMR,\;^{13}C-NMR$, and Mass spectral data and elemental analyses. The compounds were tested for antimicrobial activity using diffusion agar technique.
Synthesis of New Xanthenone Derivatives of Expected Antibilharzial Activity
Omar, Mahmoud-T. The Pharmaceutical Society of Korea 1997 Archives of Pharmacal Research Vol.20 No.6
A new series of 1, 3, 4-oxadiazoles, 1, 3, 4-thiadiazoles and 1, 2, 4-triazoles incorporated directly and/or indirectly into a xanthenone moiety at position-2-were synthesized. Some of the newly prepared compounds were biologically tested as schistosomicides in experimental animals.