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International audienceThe efficiency of a new corrosion inhibitor, the bis-(4-amino-5-mercapto-1,2,4-triazol-3-yl)-butane (BAMTB), on copper was investigated in an aerated 3% NaCl solution using various techniques. Voltammetry, chronopotentiometry and electrochemical impedance spectroscopy (EIS) were performed to evaluate the inhibition efficiency of BAMTB. The surface layers were also characterized by Raman micro-spectroscopy and by scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX). Potentiodynamic polarization curves showed that BAMTB is a mixed-type inhibitor for copper in neutral chloride solution and is even more efficient than the reference compound benzotriazole

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The synthesis of palladium complexes derived from 4-amino-3pentadecyl-3H-1,2,4-triazole-3-thiones and 3-pentadecyl-1,3,4-oxadiazole-2(3H)-thionesare reported. They were obtained from palladium acetate and dipotassium tetrachloropalladate(II) and their composition was assigned by elemental analysis (solid state). The resulting metallic entities were also characterized in solution based in mass spectrometry experiments. Their application in organic synthesis as cross-coupling reaction catalysts is described. One example of both conventional Tsuji-Trost and Mizoroki-Heck reactions were efficiently carried out in very high chemical yield.

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The ricinoleate triglyceride was extracted from castor-oil seeds grown in Algeria and isolated by catalytically methanolyse to methyl ricinoleate. Six diazole and triazole derivatives of ricinoleic acid were synthesized and characterized: 1,3,4-oxadiazole-5-thione (4); 1,3,4-thiadiazole-5-thione (5); 4-N-amino-1,2,4-triazole-5-thiol (7); 1,2,4-triazole-5-thione (9); 5-amino-1,3,4-oxadiazole (10) and 5-amino-1,3,4-thiadiazole (11). The antibacterial and antifungal screening data of synthesized compounds showed appreciable inhibition and among them, 5, 7 and 8 showed more inhibition on Gram positive Enterococcus faecalis than reference ampiciline; while compounds 1, 7, 8, 10 and 11 showed competitive antifungal effects compared to reference amphotericin B. In addition, all synthesized compounds (1-11) showed competitive antioxidant properties, particularly compounds 7 at 125, 250, 500 and 1000 μg/mL and compounds 4, 5 and 9 at a concentration of 1000 μg/mL. The intermediate compounds 1, 2 and 8 showed anti-α-amylase activity at various concentrations in the range of IC50 = (120.25 ± 1.17 - 130.42 ± 2.48). Oxadiazole 4 showed the best α-amylase inhibition by 78.5% at a concentration of 1000 μg/mL.

A series of S-glucosides 11a-14a and their benzamido derivatives 11b-14b have been synthesized by reacting D-glucose with thiol groups of 5-(2'-aminophenylene)-1,3,4-oxadiazole-2-thioles 7(a,b), 5-(2'-aminophenylene)-1,3,4-thiadiazole-2-thiols 8(a,b), 5-(2'-aminophenylene)-1,2,4-triazole-3-thiols 9(a,b) and 5-(2'-aminophenylene)-4-N-amino-1,2,4-triazole-3-thiols 10(a,b). The thiols 7(a,b)-10(a,b) have been synthesized from hydrazides 3(a,b) which already been synthesized from 2-aminobenzoic acid and its benzamido derivative. All synthesized compounds were characterized by IR, UV, 1 H-and 13 C-NMR. Nucleobases and a representative of S-glycoside were tested in vitro against the following microorganisms: two Gram-positive bacteria Staphylococcus aureus and Bacillus cereusand two Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa and they exhibited significant effects. Amykacine was used as positive standard.

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