Synthesis of diazole-thiols derivatives from L-Cysteine: Characterization, complex formation with Ni(II), Cu(II) and evaluation of their antibacterial activity

摘要: Abstract Four novel diazole-thiol derivatives namely: 5-(1-amino-2-sulfanylethyl)-1,3,4-oxadiazole-2(3H)-thione 6, 4-amino-5-(1-amino-2-sulfanylethyl)-4H-1,2,4-triazole-3-thiol 7, 1-amino-3-(1-amino-2-sulfanylethyl)-1H-1,2,4-triazole-5-thiol 8, and 5-(1-amino-2-sulfanylethyl)-1H-1,2,4-triazole-3-thiol 9 have been synthesized from l-Cysteine characterized by IR, 1H-NMR, 13C-NMR GC-MS. Complex formation with Ni(II) Cu(II) ions four of were formed isolated. The final synthetic products (6-9) their corresponding complexes (6a,a’-9a,a’) tested against Gram-negative bacteria: Escherichia coli, Pseudomonas aeroginosae Gram-positive Staphylococus aureus 25923 showed no biological activity. While 7-9 exhibited appreciable activity microorganisms. outstanding results is that the Cu(II)-complexes 8a’and 9a’ (MIC) on similar organisms at very low concentrations (5µg/ml) which in fact lower concentration than what had reported other relative compounds.