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The cover image, by Savita Beniwal et al., is based on the Full Paper Syntheses, characterization, antibacterial activity and molecular modelling of phenylantimony(III) heteroleptic derivatives containing substituted oximes and piperidine dithiocarbamate, DOI: .

Triphenylantimony(V) heteroleptic derivatives containing substituted oximes and morpholine dithiocarbamate of the type Ph3Sb[R(R′)C:NO]2[S2CN(CH2CH2)2O] (where R = ─C6H5, R′ = ─CH3 (I); R = ─C6H4CH3, R′ = ─CH3 (II); R = ─C6H4Cl, R′ = ─CH3 (III); R = ─C6H4Br, R′ = ─CH3 (IV); R = ─C6H4OH, R′ = ─H (V); R(R′)C = CCH2(CH2)3CH2 (VI)) were synthesized by successive substitution reactions of triphenylantimony(V) dibromide with the sodium salt of substituted oximes and morpholine dithiocarbamate in unimolar ratio. All these newly synthesized derivatives were characterized using physicochemical and elemental analyses and tentative structures have been proposed on the basis of infrared, (1H, 13C) NMR and liquid chromatography–mass spectra. Spectral data revealed that the oxime behaves in a monodentate manner whereas morpholine dithiocarbamate behaves in an anisobidentate manner and thus distorted octahedral geometry has been proposed for these derivatives. Nanometric particle size (ca 25 nm) and monoclinic crystal system have been determined using power X‐ray diffraction data of two representative derivatives. Furthermore, these newly synthesized derivatives were screened against two bacteria, Bacillus subtilis (Gram‐positive) and Escherichia coli (Gram‐negative), to evaluate their antibacterial potential. Derivative VI exhibited maximum zone of inhibition (30 mm) against E. coli. Additionally two derivatives (I and II) were tested for their antioxidant potential, with derivative II exhibiting higher antioxidant potential (233 μM g−1). Structure–activity relationships were also investigated.

Six new heteroleptic phenylantimony(III) derivatives containing substituted oximes and dithiocarbamate moieties of the type (where R = ─C 6 H 5 , X = ─CH 3 (2a); R = ─C 6 H 4 CH 3 , X = ─CH 3 (2b); R = ─C 6 H 4 Cl, X = ─CH 3 (2c); R = ─C 6 H 4 Br, X = ─CH 3 (2d); R = ─C 6 H 4 OH, X = ─H (2e); R(X)C = (2f)) have been synthesized by the reactions of phenylantimony(III) dichloride with the sodium salt of substituted oximes and dithiocarbamate moiety in unimolar ratio with stirring in dichloromethane. All these newly synthesized derivatives have been characterized using physicochemical and elemental analyses. Structures have been proposed on the basis of infrared, 1 H NMR, 13 C NMR and LC-MS spectral studies and molecular modelling. In these derivatives the oxime behaves in an unidentate manner whereas dithiocarbamate behaves in a monofunctional anisobidentate manner. Pseudo-trigonal bipyramidal (ψ-TBP) geometry around the antimony metal centre is proposed for these phenylantimony(III) heteroleptic derivatives. The geometry of a representative complex has been optimized through molecular modelling. These newly synthesized derivatives were screened against Bacillus subtilis (Gram-positive) and Escherichia coli (Gram-negative) bacteria to evaluate their antibacterial potential. The structureactivity relationship for antibacterial activity among the four derivatives 2a, 2c, 2e and 2f is discussed.

Consecutive substitution reactions of arsenic(III)chloride with sodium salts of various oximes and morpholinedithiocarbamate (morphdtc) were carried out in 1:2:1 stoichiometry to obtain six new arsenic(III) mixed derivatives of the type: [(R)(R1)C = NO]2Sb[S2CN(CH2CH2)2O] [where R is –C6H5, R1 = –CH3 (1); R = –C6H4CH3, R1 = –CH3 (2); R = –C6H4Cl, R1 = –CH3 (3); R = –C6H4Br, R1 = –CH3 (4); R = –C6H4OH, R1 = –H (5); R(R1)C =  (6)]. These derivatives are characterized by elemental and physicochemical analyses and the tentative distorted trigonalbipyramidal geometry around arsenic assigned using spectral data of infrared (1H, 13C) nuclear magnetic resonance and liquid chromatography‐mass. Powder X‐ray diffraction study revealed their nanoranged particle size to be approximately 40 nm and crystalline nature. These derivatives examined against microbes and results revealed that these derivatives expressed more antifungal potential than antibacterial. The antioxidant activity was carried out by ferric reducing ability of plasma assay, and the cytotoxic study was performed in 3T3 fibroblast cell lines by tetrazolium‐based colorimetric assay.