Figure 2. The effect of fractions A, B, C, D and E from the EtOAC soluble fraction of the methanolic extract of tuber-barks of C. antiquorum var. esculenta on melanogenesis in melan-a cells. Test samples were tested at three concentrations of 1, 10 and 100 μg/mL. PTU (1-phenyl-2-thiourea) was used as positive control. Test sample and medium were renewed daily. The cell viabilities and the melan...

An efficient and practical procedure for the synthesis of esonarimod, (R,S)-2-acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid (1), a new antirheumatic drug, has been developed. The intermediate, 2-methylene-4-(4-methylphenyl)-4-oxobutanoic acid (2), was prepared by Friedel-Crafts acylation of toluene with itaconic anhydride (3) in the presence of aluminum trichloride and nitrobenzene in ...

A reinvestigation of the nitrogen-14 NQR in thiourea has permitted to record, apparently for the first time, the resonances above 169 K. The first order and second order of the transitions at 169 K and 202 K, respectively, appear clearly from the temperature dependence of the resonance frequencies; the modulated structure, incommensurate or commensurate, is also seen on the N NQR spectrum. This...

The structures of diphenyl [3-methyl-1-(3-phenylthioureido)butyl]phosphonate and diphenyl [2-methyl-1-(3-phenylthioureido)butyl]phosphonate, both C(24)H(27)N(2)O(3)PS, are reported. In both compounds, the thiourea moiety adopts a syn-syn conformation (i.e. the S-C-N-C torsion angles are synperiplanar), which enables N-H...O hydrogen bonds to be formed between centrosymmetrically related molecul...

some n¬-acyl-n'-aryl thiourea derivatives 4(a-f) have been prepared by the reaction of acyl halides ammonium thiocyanate and aryl amines. the structures of synthesized compounds have been characterized by ir, 1hnmr spectral studies. the synthesized compounds 5(a-f) have been screened for antibacterial activity. the effect of the structure of the investigated compounds on the antibacterial activ...

The preparation of nanocellulose fibers (NFs) is achieved through pretreating cellulose in a NaOH/urea/thiourea solution, and then defibrillating the fibers through ultrasonication, resulting in a high yield of 85.4%. Extensive work has been done to optimize the preparation parameters. The obtained NFs are about 30 nm in diameter with cellulose II crystal structure. They possess high thermal st...

Condensation of 3-acetyl-8-ethoxycoumarin (3) with thiosemicarbazide gave ethylidenehydrazinecarbothioamide 5, which was transformed into the thiazolidin-4-one derivatives 6,7. Interaction of 3 with DMF/POCl(3) gave b-chloroacroline derivative 8. Treatment of 3 with malononitrile gave benzo[c]chromone and 2-aminobenzonitrile derivatives 9 and 10, respectively with respect to the reaction condit...

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Thiourea, as an alternative medium, is one of the most promising leaching agents for gold recovery by its commercial benefits and research challenges associated with performance environmental impacts. This review article describes operational conditions use Thiourea vs cyanide, chemistry, limitations, toxicity factors, environment, processes. Although thiourea extraction processes have not been...