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The nuclearity, bonding and H-bonded networks of copper(I) halide complexes with thiophene-2-carbaldehyde thiosemicarbazones {(C4H3S)HC2 ＝N3–N(H)–C1(＝S) N1HR} are influenced by R substituents at N1 atom. Thiophene-2-carbaldehyde-N1-methyl thiosemicarbazone (HttscMe) or thiophene-2-carbaldehyde-N1-ethyl thiosemicarbazone (HttscEt) have yielded halogen-bridged dinuclear complexes, [Cu2(μ-X)2(η1-S-Htsc)2(Ph3P)2] (Htsc, X: HttscMe, I, 1; Br, 2; Cl, 3; HttscEt, I, 4; Br, 5; Cl, 6), while thiophene-2-carbaldehyde-N1-phenyl thiosemicarbazone (HttscPh) has yielded mononuclear complexes, [CuX(η1-S-HttscPh)2] (X, I, 7a; Br 8; Cl, 9) and a sulfur bridged dinuclear complex, [Cu2(μ-S-HttscPh)2(η1-S-HttscPh)2I2] 7b co-existing with 7a in the same unit cell. These results are in contrast to S-bridged dimers [Cu2(μ-S-Httsc)2(η1-Br)2(Ph3P)2]·2H2O and [Cu2(μ-S-Httsc)2(η1-Cl)2(Ph3P)2]·2CH3CN obtained for R=H and X=Cl, Br (Httsc=thiophene-2-carbaldehyde thiosemicarbazone) as reported earlier. The intermolecular CHPh⋯π interaction in 1–3 (2.797Å, 1; 3.264Å, 2; 3.257Å, 3) have formed linear polymers, whereas the CHPh⋯X and N3⋯HCH interactions in 4–6 (2.791, 2.69Å, 5; 2.776, 2.745Å, 6, respectively) have led to the formation of H-bonded 2D polymer. The PhN1H⋯π, interactions (2.547Å, 8, 2.599Å, 9) have formed H-bonded dimers only. The Cu⋯Cu separations are 3.221–3.404Å (1–6). [Copyright &y& Elsevier]

Synthesis of Isatin-N 1 -methyl-thiosemicarbazone (H 2 itsc-N 1 -Me, H 2 L 1 ) and isatin-N 1 -ethyl-thiosemicarbazone (H 2 itsc-N 1 -Et, H 2 L 2 ) has been carried out and the effect of substituents (at N 1 atom of isatin-3-thiosemicarbazones) on nuclearity of copper(I) halide complexes has been investigated. Reactions of copper(I) halides (X = I, Br, Cl) with H 2 L 1 and H 2 L 2 using Ph 3 P as co-ligand in 1:1:1 (M:L:PPh 3 ) molar ratio in acetonitrile yielded complexes of stoichiometry [CuX(H 2 L 1 )(Ph 3 P)] (X = I, C1 ; Br, C2 ; Cl, C3 ) and [CuX(H 2 L 2 )(Ph 3 P)] (X = I, C4 ; Br, C5 ; Cl, C6 ) respectively. All these complexes have been characterized using analytical and spectroscopic data (IR, 1 H NMR and ESI mass). The single crystal structure has been solved for H 2 L 1 and C2 . The complex C2 has distorted tetrahedral geometry around copper(I) and isatin-N 1 -methyl-thiosemicarbazone coordinated to metal center as neutral, bidentate, N 3 , S-chelating ligand. Elemental analysis suggested the presence of one acetonitrile molecule in complexes C3 and C6 and half CH 3 CN in complexes C2 and C4 as solvent of crystallization. MTT assay, supported by docking studies have revealed the cytotoxic nature of the compounds C1 – C6 . [ABSTRACT FROM AUTHOR]

Enhancement in Anti-TB activity of 4-cholobenzaldehyde thiosemicarbazone on complexation: Synthesis, structure and docking studies. • Ni(II) has formed square planar complex and Silver(I) formed halogen-bridged dimers. • Ni(II) complex has shown better anti-tubercular activity as compare to free ligand. • The anti-tubercular activity has been well corroborated with molecular docking studies. • No influence of substituents at phenyl ring at C2 atom of thiosemicarbazones has been observed on its silver(I) halide complexes. Complexes of 4-chlorobenzaldehyde thosemicarbazone (H1L) with Ni(II), [Ni(1L) 2 1 and Ag(I), [Ag 2 (μ-X) 2 (η1-S-H1L) 2 (PPh 3) 2 (X = Cl, 2 ; Br, 3) have been synthesized and characterized by elemental analysis, IR and 1H NMR spectroscopy. Ag(I) complexes, containing the 4-methylbenzaldehyde thiosemicarbazone (H2L) ligand complexes [Ag 2 (μ-X) 2 (η1-S-H2L) 2 (PPh 3) 2 (X = Cl, 4 ; Br, 5) have also been synthesized. Complexes 1, 3 and 4 are also characterized by single crystal crystallography to investigate the effect of substituent at phenyl ring of the thiosemicarbazone on the bonding behavior of these Ag(I) complexes. H1L and its Ni(II) complexes were evaluated for their anti-tubercular activities and it was found that the anti-TB actitivy of H1L was enhanced on complexation with Ni(II) for complex 1. Molecular docking of H1L and its nickel complex has also been examined. The results of these studies support the molecular design of the these molecules and have provided a significant background to further examine their antitubercular activity. [ABSTRACT FROM AUTHOR]