Amna Qasem Ali

Synthesis of isatin thiosemicarbazones derivatives: in vitro anti-cancer, DNA binding and cleavage activities.

New derivatives of thiosemicarbazone Schiff base with isatin moiety were synthesized L1-L6. The structures of these compounds were characterized based on the spectroscopic techniques. Compound L6 was further characterized by XRD single crystal. The interaction of these compounds with calf thymus (CT-DNA) exhibited high intrinsic binding constant (k(b)=5.03-33.00×10(5) M(-1)) for L1-L3 and L5 and (6.14-9.47×10(4) M(-1)) for L4 and L6 which reflect intercalative activity of these compounds toward CT-DNA. This result was also confirmed by the viscosity data. The electrophoresis studies reveal the higher cleavage activity of L1-L3 than L4-L6. The in vitro anti-proliferative activity of these compounds against human colon cancer cell line (HCT 116) revealed that the synthesized compounds (L3, L6 and L2) exhibited good anticancer potency.

Synthesis of nickel(II) complexes of isatin thiosemicarbazone derivatives: in vitro anti-cancer, DNA binding, and cleavage activities

Six new nickel(II) complexes of thiosemicarbazone Schiff base with isatin moiety [Ni(L1)2–Ni(L6)2] were synthesized through reaction of Ni(II) with (Z)-2-(2-oxoindolin-3-ylidene)-N-phenylhydrazinecarbothioamide (L1H), (Z)-2-(5-methyl-2-oxoindolin-3-ylidene)-N-phenylhydrazinecarbothioamide (L2H), (Z)-2-(5-fluoro-2-oxoindolin-3-ylidene)-N-phenylhydrazinecarbothioamide (L3H), (Z)-N-methyl-2-(5-nitro-2-oxoindolin-3-ylidene)hydrazinecarbothioamide (L4H), (Z)-N-methyl-2-(5-methyl-2-oxoindolin-3-ylidene)hydrazinecarbothioamide (L5H), and (Z)-N-ethyl-2-(5-methyl-2-oxoindolin-3-ylidene)hydrazinecarbothioamide (L6H). The structures of the Ni complexes were characterized through elemental analysis, infrared, and mass spectral data. The structure of the NiL2 complex was further characterized through single-crystal X-ray diffraction. The interaction of these complexes with calf thymus (CT-DNA) exhibited high intrinsic binding constants (Kb = 1.4 × 105–2.4 × 106 M−1), which reflected their intercalative activity toward CT-DNA. This result was also confirmed by viscosity data. Electrophoresis studies revealed that these complexes could cleave the DNA through the oxidative pathway. The in vitro anti-proliferative study establishes the anticancer potency of these compounds against human colorectal carcinoma cell line. Graphical Abstract

(Z)-N-Methyl-2-(5-nitro-2-oxoindolin-3-yl­idene)hydrazinecarbothio­amide

In the title compound, C10H9N5O3S, an intramolecular N—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, molecules are linked via N—H⋯S hydrogen bonds into a zigzag chain along the b axis. C—H⋯O interactions are observed between the chains.

(Z)-2-(5-Chloro-2-oxoindolin-3-yl­idene)-N-phenyl­hydrazinecarbothio­amide

In the title compound, C15H11ClN4OS, the dihedral angle between the nine-membered 5-chloroindolin-2-one ring system and the benzene ring is 10.00 (6)°. Intramolecular cyclic N—H⋯O and C—H⋯S hydrogen-bonding interactions [graph set S(6)] are present in the N—N—C—N chain between the ring systems. In the crystal, molecules form centrosymmetric cyclic dimers through intermolecular N—H⋯O hydrogen bonds [graph-set R 2 2(8)] and are extended by C—H⋯Cl interactions into infinite chains which propagate along [100].

(Z)-2-(2-Oxoindolin-3-yl-idene)-N-phenylhydrazinecarbothio-amide.

In the title compound, C15H12N4OS, the dihedral angle between the nine-membered indolin-2-one ring system and the phenyl ring is 2.72 (7)°. Intramolecular cyclic N—H⋯O and C—H⋯S hydrogen-bonding interactions [graph set S(6)] are present, as are weak N—H⋯N interactions [graph set S(5)]. In the crystal, molecules form centrosymmetric cyclic dimers through pairs of N—H⋯O hydrogen bonds [graph set R 2 2(8)] and these are extended by C—H⋯S interactions. The crystal structure also features weak C—H⋯π interactions.

Bis[2-(2-oxoindolin-3-yl­idene)-N-phenylhydrazinecarbothio­amidato-κ3O,N2,S]nickel(II) dimethyl­formamide monosolvate

The asymmetric unit of the title compound, [Ni(C15H11N4OS)2]·C3H7NO, contains one NiII complex molecule and one disordered dimethylformamide solvent molecule. The NiII ion is six-coordinated in a distorted octahedral geometry by two N, two O and two S atoms. An intramolecular C—H⋯S hydrogen bond generates an S(6) ring motif. In the crystal, molecules are linked through intermolecular N—H⋯S, N—H⋯O, C—H⋯N, C—H⋯O and C—H⋯S hydrogen bonds into infinite two-dimensional network parallel to the ab plane. The structure is further stablized by weak C—H⋯π interactions. The dimethylformamide solvent molecule is disordered over two sets of sites in a 0.514 (15):0.486 (15) ratio.

(E)-2-[(E)-3-(Hy­droxy­imino)­butan-2-yl­idene]-N-methyl­hydrazinecarbothio­amide

In the title compound, C6H12N4OS, an intramolecular N—H⋯N hydrogen-bond is present giving rise to an S(5) ring motif. In the crystal, double-stranded chains propagating along [10] are formed via pairs of O—H⋯S and N—H⋯S hydrogen bonds. The chains are further stabilized by C—H⋯S interactions.

Bis{N-ethyl-2-[3-(hy­droxy­imino-κN)butan-2-yl­idene]hydrazinecarbothio­amide-κ2N2,S}nickel(II) dichloride

In the title complex, [Ni(C7H14N4OS)2]Cl2, the NiII ion is six-coordinated in a distorted octahedral geometry by four N atoms from the two imine and two oxime groups, and two S atoms from the thione groups. Two chloride ions complete the asymmetric unit. In the crystal, molecules are linked through N—H⋯Cl and O—H⋯Cl hydrogen bonds into an infinite chain propagating along [101].

Bis{2-[3-(hy­droxy­imino-κN)butan-2-yl­idene]-N-methyl­hydrazinecarbothio­amide-κ2N2,S}nickel(II) dichloride

The asymmetric unit of the title compound, [Ni(C6H12N4OS)2]Cl2, contains two independent NiII complex cations and four chloride anions. Each NiII ion is six-coordinated in a distorted octahedral geometry by four N atoms from the two imine and two oxime groups and two S atoms from the thione group. In the crystal, the cations and anions are linked through N—H⋯Cl and O—H⋯Cl hydrogen bonds into infinite chains propagating along [10]. Weak intermolecular C—H⋯O and C—H⋯Cl hydrogen bonds are also observed.

(Z)-N-Ethyl-2-(5-fluoro-2-oxoindolin-3-yl­idene)hydrazinecarbothio­amide

In the title compound, C11H11FN4OS, an intramolecular N—H⋯O hydrogen bond generates an S(6) ring. In the crystal, molecules form chains through N—H⋯O hydrogen bonds, which are extended by N—H⋯S hydrogen bonds into an infinite three-dimensional network.