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Graphical abstract Equimolar reactions of copper(I) halides with PPh 3 and pyridine-2-carbaldehyde-N-substituted thiosemicarbazone (C 5 H 4 N)HC2 N3N2(H)-C1(S)N1HR has yielded complexes, [CuX 2 (κS1-H 2 L1-R)(PPh 3)] 1–5 (X = halogen, R = Me, Et) with pyridine protonated thio-ligand. Similar reactions of copper(I) halides with benzaldehyde-N1-substituted thiosemicarbazones (C 6 H 5)HC2 N3-N2(H)-C1(S)-N1HR and Ph 3 P halogen bridged dinuclear complexes, [Cu 2 (μ-X) 2 (κS1-HL2-R) 2 (Ph 3 P) 2 ] 6–10 (X = halogen, R = Me, Et) or sulfur-bridged dinucelar complexes [Cu 2 (μ-S-HL2-Ph) 2 (κS1-HL2-Ph) 2 X 2 ] 11–13 with no Ph 3 P coordination. The substitutions at N1, C2 and order of reactants with change in solvent appear to have yielded three types of products. Abstract Equimolar reaction of copper(I) iodide with PPh 3 in acetonitrile formed compound of empirical composition, {CuI(Ph 3 P)} and its further reaction in chloroform with pyridine-2-carbaldehyde-N-methyl thiosemicarbazone {(C 5 H 4 N)HC2 N3-N2-(H)-C1(S)N1HR; R = Me; HL1-Me} formed crystals of complex, [CuICl(Ph 3 P)(κS1-H 2 L1-Me] 1a , tetramer [Cu 4 I 4 (Ph 3 P) 4 ] 1b and free HL1-Me 1c , separated from the same reaction vessel. The formation of product 1a involved abstraction of chlorine from chloroform and has pyridine-N-protonated thio-ligand. Copper(I) bromide/chloride with Ph 3 P and HL1-Me or HL1-Et also formed pyridyl protonated, [CuBr 2 (Ph 3 P)(κS1-H 2 L1-Me)] 2 , [CuCl 2 (Ph 3 P)(κS1-H 2 L1-Me)] 3 , [CuBr 2 (Ph 3 P)(κS1-H 2 L1-Et)] 4 and [CuCl 2 (Ph 3 P)(κS1-H 2 L1-Et)] 5. The products similar to 1b and 1c were also identified in these reactions. In these four coordinated complexes the pyridine protonated thio-ligands are coordinating through sulfur only. Copper(I) halides with benzaldehyde-N1-substituted thiosemicarbazones {(C 6 H 5)HC2 N3-N2(H)-C1(S)-N1HR ; R = Me, Et; HL2-Me; HL2-Et} and Ph 3 P have yielded halogen bridged dinuclear complexes, [Cu 2 (μ-X) 2 (κS1-HL2-R) 2 (Ph 3 P) 2 ] (X, R: I, Me, 6 ; Br, Me, 7 ; I, Et, 8 ; Br, Et, 9 ; Cl, Et, 10). For R = phenyl at N1 atom, copper(I) halides with two m moles of HL2-Ph have formed sulfur–bridged dinucelar complexes, namely, [Cu 2 (μ-S-HL2-Ph) 2 (κS1-HL2-Ph) 2 X 2 ] (X = I, 11 , Br, 12 , Cl, 13). Complexes have been characterized using analytical data, IR, proton NMR and single crystal X-ray crystallography (1–5, 7, 9, 11 and 12). The coordination environment of the Cu in complex 1a contains both Cl and I, but both sites are disordered. [ABSTRACT FROM AUTHOR]

The effect of the substituents at the N 1 /C 2 atoms of the thiosemicarbazones R 1 R 2 C 2 = N 3 -N 2 H-C 1 (=S)-N 1 HR 3 on the type of gold(I) complexes is investigated. Direct reaction of gold(I) chloride with benzaldehyde-N-methyl thiosemicarbazones (HL 1 : R 1 = Ph, R 2 = H, R 3 = Me) in a 1:2 M ratio in acetonitrile has yielded an ionic complex, [Au(κ 1 -S-HL 1 ) 2 ]Cl ( 1 ). Similarly, the reaction of benzaldehyde-N-ethyl thiosemicarbazone (HL 2 : R 1 = Ph, R 2 = H, R 3 = Et) has formed another ionic complex, [Au(κ 1 -S-HL 2 ) 2 ]Cl ( 2 ). The complexes have been characterized using analytical data, spectroscopy (IR, 1 H, 13 C NMR, UV–Vis), fluorescence, ESI-mass and X-ray crystallography. Complexes 1 and 2 represent the first examples obtained from the direct reactions of gold(I) chloride with a thio-ligand without the presence of PPh 3 or the use of any intermediate substrate, as has normally been used. Complex 1 , with a methyl substituent at N 1 , has two independent molecules in the crystal lattice, while complex 2 , with an N-ethyl substituent, has only one type of molecule in the crystal lattice. ESI-mass studies reveal the formation of the species: [Au I Cl+H] + ( A ), [Au I Cl 2 (HL 1 )+2H] + ( B ), [Au I (HL 1 ) 2 ] + ( C ) (complex 1 ) and [Au I (HL 2 ) 2 -4H] + ( D ) (complex 2 ). Interestingly both complexes have shown intense fluorescence bands in the wide region 340–540 nm, corresponding to the excitation wavelength of 308 nm. [ABSTRACT FROM AUTHOR]

The chemistry of copper(I) halides (CuX) with furan-2-carbaldehyde-N1-substituted thiosemicarbazones {(C4H3O)HC2N3N2H–C1(S)N1HR, Hftsc-N1HR} in presence of triphenyl phopshine is described. For methyl and ethyl substituents (R) at N1 atom, and with X = I, Br, Cl, the halogen-bridged dimers, namely, [Cu2(μ-X)2(η1-S-Hftsc-N1HR)2(PPh3)2] (R, X: Me, I, 1, Br 2, Cl 3; Et, I 4, Br 5, Cl 6) have been obtained.However, the presence of phenyl substituent at N1 has favored a three coordinate complex, [CuI(η1-S-Hftsc-N1HPh)2] 7, and with copper(I) bromide/and chloride, it has formed sulfur-bridged dimers, [Cu2X2(η1-Hftsc-N1HPh)2(μ-S-Hftsc N1HPh)2] (X = Br 8, Cl 9). In the latter three complexes (7–9), the Ph3P ligand did not take part in coordination. All these complexes have been characterized with the help of elemental analysis, IR, 1H NMR spectroscopy and X-ray crystallography (1–3, 5, 7 and 9). The bonding and nuclearity of complexes has been found to vary with the substituents at N1 atom. The intermolecular interactions have formed one dimensional (1, 9) and two dimensional (2, 3 and 5) networks. [ABSTRACT FROM AUTHOR]

Abstract: The reactions of silver(I) halides (Cl or Br) with thiophene-2-carbaldehyde N1-methyl thiosemicarbazone (HttscMe) in the presence of Ph3P (1:1:1 molar ratio) yield halogen-bridged dimers, [Ag2(μ-X)2(η1-S-HttsMe)2(PPh3)2] (X=Cl, 1; Br, 2). The use of 2,2′-bipyridine in lieu of Ph3P in the reaction of silver(I) chloride with HttscMe yields the sulfur-bridged dimer, [Ag2(μ-S-HttscMe)2(η1-HttsMe)2]·2CHCl3 3. The substituents have altered the nature of bridge between the two silver atoms. The Ag···Ag separation (3.4867(5)Å) in complex 3 is less than that in the halogen-bridged dimers (3.734(4)Å1; 3.746(5)Å2). Unlike PPh3 the co-ligand 2,2′-bipyridine did not coordinate to the silver center, but was necessary for crystallization in the reaction with the thio-ligand. NMR spectroscopy revealed that the complexes remained unchanged in the solution state (CDCl3). [Copyright &y& Elsevier]

[Display omitted] Reaction of copper(II) acetate with cyclohexanoneselenosemicarbazone (Hcysesc), 5-chloro isatinselenosemicarbazone (5-ClHIstsesc), 1-methyl isatinselenosemicarbazone (1-MeHIstsesc), 3-indole selenosemicarbazone (3-HInsesc), 3-acetylindole selenosemicarbazone (3-AcHInsesc and 2-naphthaldehyde selenosemicarbazone (2-Hnaphsesc) in 1:2 (M: L) molar ratio yielded complexes of stiochiometry, [Cu(L) 2 ] 1 – 6 (L = cysesc 1 ; 5-ClIstsesc 2 ; 1-MeIstsesc 3 ; 3-Insesc 4 ; 3-AcInsesc 5 ; 2-naphsesc 6). All the complexes are characterized by IR, Mass and ESR spectroscopy. Two well defined g values (g ‖ and g ⊥) in ESR spectrum of complexes 1 – 4 , 6 indicate axial symmetry, whereas symmetry around copper(II) metal in complex 5 is confirmed by three different g values (g 1 , 2.095; g 2 , 2.15; g 3 , 2.26), which supports rhombic distortion. The value of g ‖ obtained is greater than g ⊥, which is greater than g e, in 1 – 4 , 6 is in well agreement in d x2-y2 ground term of square planar geometry. The value of empirical factor f for complexes 1 – 4, 6 lies in the range, 102–135 cm indicating a square planar geometry with small distortion, where as in complex 5 value (f = 146 cm) is in conformity of tetrahedral geometry with larger distortion. All the compounds (selenosemicabazones and their complexes) are tested for DPPH radical scavenging, ABTS radical scavenging, FRAP ferric reducing and CUPRAC cupric reducing antioxidant capacity assay and all the compounds have shown good antioxidant capacity in general. Best results are obtained for H1L with FRAP, 6.75 ± 0.01 μg TE/ml and CUPRAC, 9.52 ± 0.07 μg TE/ml. All the compounds are also tested for their anti-tubercular activity against M. tuberculosis H37RV strain ATCC27294. Ligands, H1L , H3L , H6L and complex 6 have shown highest anti-TB activity (MIC = 1.6 µg/ml) which is similar to the standard drugs (Isoniazid, Ethambutol). anti-TB activity of H2L and H5L (MIC = 12.5 µg/ml and 25 µg/ml) increased on complexation with copper(II) (MIC = 1.6 µg/ml, 2 ; 12.5 µg/ml, 6). Experimental results are supported by molecular modeling studies, where a considerable intermolecular interaction of these compounds with the active site of amino acid of enoyl reductase from M. tuberculosis has been observed with minimum binding energy −6.2, −7.3, −7.7, −7.4, −7.2, −8.7 Kcal/mol for H1L , H2L , H3L , H4L , H5L , and H6L and −7.2, −9.4, −8.6, −9.3, −9.9, and −10.6 Kcal/mol for copper complexes 1, 2, 3, 4, 5 and 6 exhibited respectively. [ABSTRACT FROM AUTHOR]