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We report a novel series of chiral monometallic dithiocarbamate complexes with pendant phenolic groups, formulated as [M{κ2S^S-S2CN(CH2PhOH)(CH(S-CH3))(NaPh)}2] (M = Ni(II) S,S-1, Cu(II) S,S-2, Zn(II) S,S-3) and [M{κ2S^S-S2CN(CH2PhOH)(CH(R-CH3))(NaPh)}2] (M = Ni(II) R,R-4, Cu(II) R,R-5, Zn(II) R,R-6). These compounds were synthesized through a process involving chiral amino precursors S-HL1, R-HL2, CS2 and the corresponding metal acetates. All the compounds have been characterized by microanalysis and standard spectroscopic methods such as 1H and 13C{1H}NMR, IR, UV-visible absorption and EPR spectroscopy. The spectral data suggest a square planar coordination geometry around the nickel(II) and copper(II) centers and a tetrahedral coordination geometry around zinc(II), which is corroborated by density functional theory calculations. The unprecedented molecular structures of imine precursors S-I, R-I and Ni(II)-dithiocarbamate complex S,S-1 were elucidated by single crystal X-ray diffraction (SCXRD), and their crystal packing patterns were studied. Evidently, the change in chirality could not induce changes in the donor–acceptor sites of S-I and R-I, and their molecules are primarily stabilized by O–H⋯N and C–H⋯π interactions, forming a 2D sheet-like structure in the ab-plane. Notably, the chiral S,S-1 complex crystallized in a monomeric achiral space group (triclinic, P1) in which two dithiocarbamate ligands are bonded to the nickel(II) ion in a S^S chelating mode forming a square planar geometry around the metal center. The photophysical properties of all the compounds have been investigated using UV-visible absorption, emission, and thermogravimetric analyses. Compounds exhibited intense blue photoluminescence with maximum emissions in the 330–336 nm region upon excitation in the UV region. A molecular docking study was performed to validate the potentials of these compounds in protein–ligand interactions against B-DNA Dodecamer (PDB Id: 1BNA) and cyclins (PDB Id: 1w98), which are indeed essential proteins of the cell cycle, and their proper functioning is necessary for the human health. [ABSTRACT FROM AUTHOR]

A series of stimuli-responsive AIEgens of tetraphenylethylene (TPE) fused imidazole derivatives (1–7) were synthesized, and their substituent controlled fluorescence properties in the solid state were explored. The structure of the synthesised compounds was characterized by NMR, mass and single crystal X-ray diffraction spectroscopy techniques. 1–7 exhibited a typical aggregation induced emissive (AIE) behaviour in the THF : water mixture. These compounds exhibited substituent dependent strong solid state fluorescence (Φf = 16.6–55.7%) with a tunable λmax between 458 and 496 nm. Chlorine substituted 6 showed the highest fluorescence efficiency (Φf = 55.7%), whereas acetyl substituted 3 exhibited the lowest fluorescence efficiency (Φf = 16.6%). All the seven compounds showed a mechanical pressure induced reversible fluorescence switching. Crushing 1–7 resulted in red shifted fluorescence, which was reversed to its initial state by heating/solvent vapour exposure. Interestingly, integration of 1–7 into a hydrophobic PMMA polymer resulted in blue shifted fluorescence at 470 nm, whereas that into hydrophilic PVA polymer resulted in red shifted fluorescence at 491 nm. Thus highly solid state emissive TPE fused imidazole compounds were prepared, and their stimuli-induced reversible fluorescence switching and polymer controlled tunable fluorescence were demonstrated. [ABSTRACT FROM AUTHOR]

Potassium salts of phenolate based polydentate xanthate ligands 4,4′-bis(2-dithiocarbonatobenzylideneamino)diphenyl ether (K2xan1) and 4,4′-bis(2-dithiocarbonatonaphthylmethylideneamino)diphenyl ether (K2xan2) have been synthesized and characterized, prior to use. The reaction of K2xan1 or K2xan2 with M(OAc)2 in Et3N affords access to a rare series of binuclear metallomacrocyclic xanthate complexes of the type [M2-μ2-bis-(κ2S,S-xan1/xan2)] (1–4) which quickly forms [2 : 2] binuclear N,O-bidentate Schiff base macrocyclic complexes of the type [M2-μ2-bis-(κ2N,O-L1/L2)] (L1 = 4,4′-bis(2-hydroxybenzylideneamino)diphenyl ether, L2 = 4,4′-bis(2-hydroxynaphthylmethylidene-amino)diphenyl ether) 5–8via evolution of CS2 in solution. The compounds were characterized by microanalysis, relevant spectroscopy (FT-IR, UV-visible), mass spectrometry (ESI-MS), and powder and single crystal XRD techniques. In vitro anticancer activity of all the compounds was evaluated against HEP 3B (hepatoma) and IMR 32 (neuroblastoma) by the MTT assay. Remarkably, the binuclear copper(ii) xanthate complexes were found to be extremely active against both the cell lines (IC50: 8.1 ± 0.8 μM (3), 8.8 ± 1.7 μM (4) against HEP 3B and 1.9 ± 0.3 μM (3) and 7.3 ± 0.6 μM (4) against IMR 32) and this projects them as good candidates for potent antitumor agents and the IC50 values confirm their better potency than the reference drug cisplatin. The flow-cytometric density plot illustrates the induction of apoptosis in HEP 3B and IMR 32 cells after treatment with K2xan1, 1, 3, 6 and 7. [ABSTRACT FROM AUTHOR]

The structural analysis of a cobalt(III) complex [Co(HL)2](OAc).H2O (1) [H2L = N-(2-hydroxyethyl)-3- methoxysalicylaldimine] reveals a tridentate chelation behaviour of the ligand H2L having a distorted octahedral coordination environment around the cobalt(III) center with a CoN2O4 chromophore. 1 behaves as an effective catalyst towards the oxidation of 3,5-di-tert-butylcatechol in different solvents, viz. dichloromethane (DCM), methanol (MeOH) and acetonitrile (MeCN) to its corresponding quinone derivative in aerial oxygen. The reaction follows Michaelis-Menten enzymatic reaction kinetics with turnover numbers (Kcat), 1.46 × 103, 1.21 × 103 and 2.16 × 103 h-1 in DCM, MeOH and MeCN, respectively. [ABSTRACT FROM AUTHOR]

Potassium salts of phenolate based polydentate xanthate ligands 4,4'-bis(2-dithiocarbonatobenzylideneamino)diphenyl ether () and 4,4'-bis(2-dithiocarbonatonaphthylmethylideneamino)diphenyl ether () have been synthesized and characterized, prior to use. The reaction of or with M(OAc)2 in Et3N affords access to a rare series of binuclear metallomacrocyclic xanthate complexes of the type [M2-μ(2)-bis-(κ(2)S,S-xan(1)/xan(2))] () which quickly forms [2 : 2] binuclear N,O-bidentate Schiff base macrocyclic complexes of the type [M2-μ(2)-bis-(κ(2)N,O-L(1)/L(2))] ( = 4,4'-bis(2-hydroxybenzylideneamino)diphenyl ether, = 4,4'-bis(2-hydroxynaphthylmethylidene-amino)diphenyl ether) via evolution of CS2 in solution. The compounds were characterized by microanalysis, relevant spectroscopy (FT-IR, UV-visible), mass spectrometry (ESI-MS), and powder and single crystal XRD techniques. In vitro anticancer activity of all the compounds was evaluated against HEP 3B (hepatoma) and IMR 32 (neuroblastoma) by the MTT assay. Remarkably, the binuclear copper(ii) xanthate complexes were found to be extremely active against both the cell lines (IC50: 8.1 ± 0.8 μM (), 8.8 ± 1.7 μM () against HEP 3B and 1.9 ± 0.3 μM () and 7.3 ± 0.6 μM () against IMR 32) and this projects them as good candidates for potent antitumor agents and the IC50 values confirm their better potency than the reference drug cisplatin. The flow-cytometric density plot illustrates the induction of apoptosis in HEP 3B and IMR 32 cells after treatment with , , , and .

A flip-flop extended water structure assists the formation of sulfate anion helices (both left- and right-handed) in a crystalline hydrate of a simple organic-inorganic compound [C6H10N2]SO4. 1.5H2O (1).