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The linear linker bis(4-imidazol-1-ylphenyl)diazene (L) has been used to construct eight new coordination polymers with Zn(II), Cd(II) and Co(II) metal ions and different carboxylate donor ligands, viz., 1,1′-ferrocenedicarboxylic acid (H2Fc), 2′,5′-dimethylterphenyl-4,4″-dicarboxylic acid (H2MDA), diphenic acid (H2DPA), biphenyl-4,4′-dicarboxylic acid (H2BIPH), 4,4′-oxybis (benzoic acid) (H2BIOXY), l-(−)-malic acid (H3LMA) and 2,2′-dibromo-6,6′-dinitrobiphenyl-4,4′-dicarboxylic acid (H2DBDPA). Compounds formed solvothermally are {[Cd(L)(Fc)(H2O)]·(H2O)2} n (1), {[Cd(L)(MDA)]·DMF·CH3OH} n (2), {[Zn(L)(MDA)]·3H2O} n (3), {[Cd(L)(DPA)]} n (4), {[Cd2(L)2(BIPH)2(H2O)2]·H2O} n (5), {[Cd2(L)2(BIOXY)2]·H2O·CH3OH} n (6), {[Zn3(L)5(LMA)2]·2.5H2O} n (7) and {[Co(L)(DBDPA)]·H2O} n (8). All the complexes have been characterized by single crystal X-ray diffraction, IR spectroscopy, thermogravimetry, elemental analysis and powder X-ray diffraction (PXRD). Interestingly, all complexes topologically exhibit 4-connected net except complex 7, which is (4,6). Moreover, the degree of interpenetration varies in 1–8. Complexes 1, 4 and 6 exhibit commonly occurring sql topology, while complexes 2 and 3 are 8-fold interpenetrated dia net. Contrary to this, complexes 5 and 8 show rare cdl and dmp nets with three and five mutual interpenetrative nets, respectively. However, 7 forms a novel pkb6 topological net with 2-fold interpenetration. Upon excitation at 322 nm, complexes 1–8 exhibit solid-state luminescence at room temperature.

The Schiff base (L), synthesized from 2-(dimethylamino)ethylamine and salicylaldehyde acts as a tridentate ligand. This ligand, when stirred with 1 equiv of KOH in methanol, undergoes partial hydrolysis of the imine bond. This solution readily takes up Mn(II)/Mn(III) acetate or Fe(III) chloride/perchlorate to form mixed-ligand Mn(III) or Fe(III) complexes, respectively. The neutral dark brown complex, [Mn(L- H)(NCS){o-(CHO)C6H4O-}] (1), crystallizes in the presence of thiocyanate in the orthorhombic space group Pbca with a = 15.271(8), b = 19.522(7), c = 13.213(7) Å; Z = 8; R = 0.060; and R w = 0.062. The coordination geometry around Mn(III) ion is distorted octahedral with donation from one L - H, one salicylaldehyde and, one thiocyanate ligand. With Fe(III), the dark red complex isolated in the solid state is found to be a neutral μ-oxo Fe(III) dimer with the formula [{o-(CHO)C6H4O-}(L- H)Fe]2O (3). The structure of 3 has been solved and successfully refined in the monoclinic space group C2/c with a = 18.558(7), b = 11.231(5), c = 16.943(6) Å; β = 95.81(3)°; Z = 4; R = 0.052; and R w = 0.055. Each of the Fe(III) ions is hexadentate with donation from one L - H and one salicylaldehyde besides the bridged O atom. The Fe(III)−O−Fe(III) angle is found to be 166.05(4)°, which is well within the normal range observed for monobridged Fe(III)−O−Fe(III) complexes. Due to structural trans effects, the coordination geometry around each metal center is distorted from the ideal octahedral geometry. Cu(II) makes the neutral complex, [Cu(L- H){o-(CHO)C6H4O-}] (2) when L, salicylaldehyde, and a Cu(II) salt are allowed to react in equimolar quantities in the presence of excess of KOH. It crystallizes in the monoclinic space group C2/c with a = 18.077(4), b = 11.514(2), c = 16.716(4) Å; β = 93.66(2)°; Z = 8; R = 0.057; and R w = 0.061. The coordination geometry around Cu(II) is square pyramidal where, out of the four equatorial donors, three are provided by the Schiff base L and the fourth one by the phenolate O of the salicylaldehyde group. The Cu(II) ion is 0.170(5) Å above the equatorial plane and is bonded axially to the O atom of the carbonyl group of the salicylaldehyde. The bound salicylaldehyde in the Mn(III) complex 1 readily reacts with the reagents 2-aminophenol, 2-aminothiophenol, or 2-aminoethanol to form mononuclear, neutral Mn(III) complexes 4−6, respectively, with the general formula,[Mn(L- H)(L‘- 2H)]. The Schiff base L‘ is formed by condensation of the bound salicylaldehyde in 1 with the amino group of the added reagent. Complex 4 is low-spin (μeff/μB = 3.01; S = 1) at 300 K, which is quite rare. It also exhibits a pseudoreversible Mn(IV)/Mn(III) couple with E 1/ 2 = 0.54 V (vs SCE) in DMF. All the other Mn complexes are high-spin (μeff/μB range, 4.89−4.94; S = 2) at 300 K. The μeff/μB number for 2 is 1.93 and for 3 is 1.84. Complex 2 shows catalytic activity in the oxidation of olefins to epoxides in the presence of 2-methylpropanal and molecular oxygen.

Bacteriophages are being considered as a promising natural resource for the development of alternative strategies against mycobacterial diseases, especially in the context of the wide-spread occurrence of drug resistance among the clinical isolates of Mycobacterium tuberculosis. However, there is not much information documented on mycobacteriophages from India. Here, we report the isolation of 17 mycobacteriophages using Mycobacterium smegmatis as the bacterial host, where 9 phages also lyse M. tuberculosis H37Rv. We present detailed analysis of one of these mycobacteriophages - PDRPv. Transmission electron microscopy and polymerase chain reaction analysis (of a conserved region within the TMP gene) show PDRPv to belong to the Siphoviridae family and B1 subcluster, respectively. The genome (69 110 bp) of PDRPv is circularly permuted double-stranded DNA with ∼66% GC content and has 106 open reading frames (ORFs). On the basis of sequence similarity and conserved domains, we have assigned function to 28 ORFs and have broadly categorized them into 6 groups that are related to replication and genome maintenance, DNA packaging, virion release, structural proteins, lysogeny-related genes and endolysins. The present study reports the occurrence of novel antimycobacterial phages in India and highlights their potential to contribute to our understanding of these phages and their gene products as potential antimicrobial agents.

The imidazole donor ligand bis(4-imidazol-1-ylphenyl)-diazene (azim) reacts readily with M(ClO 4 ) 2 •6H 2 O [M(II) = Zn(II) and Cu(II)] salts at room temperature to afford 4) are obtained in moderate yields. Complexes 1 and 2 crystallize as 2D fourconnected 4 4 sql networks with rectangular and rhombus grids, respectively. The frameworks are stabilized by an intricate array of hydrogen bonding interactions with guest molecules that also results in overall 3D frameworks. On the other hand, complexes 3 and 4 form 1D zigzag infinite chain structures. All compounds have been characterized by single-crystal X-ray diffraction, IR spectroscopy, thermogravimetric analysis (TGA), and powder X-ray diffraction (PXRD) measurements. The TGA and PXRD measurements reveal that the integrity of the frameworks 1 and 2 is maintained upon guest removal. N 2 and CO 2 adsorption measurements were carried out for evacuated frameworks 1 and 2, and the adsorption studies show CO 2 selectivity over N 2 at low pressure in the case of 2. Interestingly, heat and guest induced bicycle pedal motion of the azo moiety can be observed in 1 and 4 without loss of crystallinity. Upon excitation at 304 nm, compounds 1−4 and 4′ exhibit solid-state luminescence at room temperature.