The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Rasha Barwa - One of the best experts on this subject based on the ideXlab platform.
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synthesis of some new 1 2 4 triazolo 3 4 b 1 3 4 thiadiazines and 1 2 4 triazolo 3 4 b 1 3 4 thiadiazoles starting from 5 nitro 2 furoic acid and evaluation of their antimicrobial activity
Bioorganic & Medicinal Chemistry, 2011Co-Authors: Sahar M I Badr, Rasha BarwaAbstract:Abstract New series of fused 1,2,4-Triazoles such as, 6-(aryl)-3-(5-nitrofuran-2-yl)-5,6-dihydro-[1,2,4]triazolo[3,4- b ][1,3,4]thiadiazoles 4 – 8 , 6-(alkyl/aryl amino)-3-(5-nitrofuran-2-yl)-[1,2,4]triazolo[3,4- b ][1,3,4]thiadiazoles 9 – 13 and 6-(4-substituted phenyl)-3-(5-nitrofuran-2-yl)-7 H- [1,2,4]triazolo[3,4- b ][1,3,4]thiadiazines 14 – 18 have been synthesized via the reaction of 4-amino-5-(5-nitrofuran-2-yl)-4 H -1,2,4-Triazole-3-thiol 3 with various reagents such as hetero aromatic aldehydes, alkyl/aryl isothiocyanates and 4-substituted phenacyl bromides, respectively. The structures of the newly synthesized compounds have been confirmed on the basis of elemental analysis and spectral studies. The newly synthesized triazolo derivatives have been investigated for their in vitro antibacterial activity. Most of the tested compounds showed interesting antibacterial activity against Staphylococcus aureus . Furthermore, the most potent antibacterial compounds 11 – 13 were evaluated for their in vitro cytotoxic activity against human cancer cell lines. It was found that compounds 11 and 13 showed higher cytotoxicity against Hep-G2 cell line as compared to standard.
Chris H Senanayake - One of the best experts on this subject based on the ideXlab platform.
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regioselective synthesis of polysubstituted n2 alkyl aryl 1 2 3 Triazoles via 4 bromo 5 iodo 1 2 3 Triazole
Synlett, 2012Co-Authors: Li Zhang, Xiaojun Wang, Nathan K Yee, Chris H SenanayakeAbstract:The regioselective N2-substitution of 4-bromo-5-iodo-1,2,3-Triazole with alkyl/aryl halides in the presence of K2CO3 in DMF produced the desired 2-substituted 4-bromo-5-iodo-1,2,3-Triazoles as a major products in good to excellent regioselectivity. Subsequent chemoselective Suzuki–Miyaura cross-coupling reaction of N2-substituted 4-bromo-5-iodo-1,2,3-Triazoles provided polysubstituted 1,2,3-Triazoles efficiently.
Evangelia D Chrysina - One of the best experts on this subject based on the ideXlab platform.
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synthesis of variously coupled conjugates of d glucose 1 3 4 oxadiazole and 1 2 3 Triazole for inhibition of glycogen phosphorylase
Carbohydrate Research, 2011Co-Authors: Sandor Kun, Gergő Nagy, Marietta Toth, Laura Czecze, Albert Nguyen Van Nhien, Tibor Docsa, Pal Gergely, Mariadespoina Charavgi, Paraskevi V Skourti, Evangelia D ChrysinaAbstract:Abstract 5-(O-Perbenzoylated-β- d -glucopyranosyl)tetrazole was obtained from O-perbenzoylated-β- d -glucopyranosyl cyanide by Bu 3 SnN 3 or Me 3 SiN 3 –Bu 2 SnO. This tetrazole was transformed into 5-ethynyl- as well as 5-chloromethyl-2-(O-perbenzoylated-β- d -glucopyranosyl)-1,3,4-oxadiazoles by acylation with propiolic acid–DCC or chloroacetyl chloride, respectively. The chloromethyl oxadiazole gave the corresponding azidomethyl derivative on treatment with NaN 3 . These compounds were reacted with several alkynes and azides under Cu(I) catalysed cycloaddition conditions to give, after removal of the protecting groups by the Zemplen protocol, β- d -glucopyranosyl-1,3,4-oxadiazolyl-1,2,3-Triazole, β- d -glucopyranosyl-1,2,3-triazolyl-1,3,4-oxadiazole, and β- d -glucopyranosyl-1,3,4-oxadiazolylmethyl-1,2,3-Triazole type compounds. 5-Phenyltetrazole was also transformed under the above conditions into a series of aryl-1,3,4-oxadiazolyl-1,2,3-Triazoles, aryl-1,2,3-triazolyl-1,3,4-oxadiazoles, and aryl-1,3,4-oxadiazolylmethyl-1,2,3-Triazoles. The new compounds were assayed against rabbit muscle glycogen phosphorylase b and the best inhibitors had inhibition constants in the upper micromolar range (2-phenyl-5-[1-(β- d -glucopyranosyl)-1,2,3-triazol-4-yl]-1,3,4-oxadiazole 36: K i = 854 μM, 2-(β- d -glucopyranosyl)-5-[1-(naphthalen-2-yl)-1,2,3-triazol-4-yl]-1,3,4-oxadiazole 47: K i = 745 μM).
Mikhail L Zheludkevich - One of the best experts on this subject based on the ideXlab platform.
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corrosion inhibition of copper in aqueous chloride solution by 1h 1 2 3 Triazole and 1 2 4 Triazole and their combinations electrochemical raman and theoretical studies
Physical Chemistry Chemical Physics, 2017Co-Authors: Stanley Udochukwu Ofoegbu, Tiago L P Galvao, Jose R B Gomes, Joao Tedim, Helena I S Nogueira, M G S Ferreira, Mikhail L ZheludkevichAbstract:Triazoles are well-known organic corrosion inhibitors of copper. 1H-1,2,3-Triazole and 1,2,4-Triazole, two very simple molecules with the only difference being the positions of the nitrogen atoms in the Triazole ring, were studied in this work as corrosion inhibitors of copper in 50 mM NaCl solution using a set of electrochemical and analytical techniques. The results of electrochemical tests indicate that 1H-1,2,3-Triazole exhibited superior inhibitor properties but could not suppress anodic copper dissolution at moderate anodic potentials (>+300 mV SCE), while 1,2,4-Triazole, although it exhibited higher anodic currents, suppressed anodic copper dissolution at very anodic potentials. Density functional theory calculations were also performed to interpret the measured data and trends observed in the electrochemical studies. The computational studies considered either the inhibitors isolated in the gaseous phase or adsorbed onto Cu(111) surface models. From the calculations, the mechanisms of the inhibitive effects of both Triazoles were established and plausible mechanisms of formation of the protective films on the Cu surface were proposed. The results of this study hold positive implications for research in the areas of catalysis, and copper content control in water purification systems.
A Pitsas - One of the best experts on this subject based on the ideXlab platform.
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synthesis of novel sulfonamide 1 2 4 Triazoles 1 3 4 thiadiazoles and 1 3 4 oxadiazoles as potential antibacterial and antifungal agents biological evaluation and conformational analysis studies
Bioorganic & Medicinal Chemistry, 2012Co-Authors: Panagiotis Zoumpoulakis, Ch Camoutsis, George Pairas, Constantinos Potamitis, Marina Sokovic, Jasmina Glamočlija, A PitsasAbstract:Abstract The significant antifungal activity of a series of sulfonamide-1,2,4-Triazole and 1,3,4-thiazole derivatives against a series of micromycetes, compared to the commercial fungicide bifonazole has been reported. These compounds have also shown a comparable bactericidal effect to that of streptomycin and better activity than chloramphenicol against various bacteria. In view of the potential biological activity of members of the 1,2,4-Triazole, 1,3,4-thiadiazole and 1,3,4-oxadiazole ring systems and in continuation of our search for bioactive molecules, we designed the synthesis of a series of novel sulfonamide-1,2,4-Triazoles, -1,3,4-thiadiazoles and -1,3,4-oxadiazoles emphasizing, in particular, on the strategy of combining two chemically different but pharmacologically compatible molecules (the sulfomamide nucleus and the five member) heterocycles in one frame. Synthesized compounds were tested in vitro for antibacterial and antifungal activity and some analogues exhibited very promising results especially as antifungal agents. In order to explain structure–activity relationships, conformational analysis was performed for active and less active analogues using NMR spectroscopy and molecular modeling techniques. Furthermore, molecular properties which can be further used as descriptors for SAR studies, were predicted for the synthesized analogues. In general, antifungal activity seems to depend more on the triazol-3-thione moiety rather than the different length of the alkyl chain substitutions.
