Synthesis,characterization and antibacterial activity of some new pyrazole based Schiff bases

In the present study a series of new Schiff bases were synthesized. All the synthesized compounds were characterized by IR, ¹H NMR, mass spectral and elemental analyses. Newly synthesized compounds were screened for their antibacterial (Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa) activity. The results revealed that, compounds 3f and 3c have exhibited significant biological activity against the tested microorganisms.     

Synthesis and performance characterization of PS-PPEES nanoporous membranes with nonwoven porous support

The present work describes about the synthesis and characterization of Polysulfone blend nanoporous membrane with nonwoven support. This Nonwoven support provides mechanical strength to membrane while filtration process and minimizes membrane fouling. Hence it helps in better membrane performance in terms of salt rejection, improved flux, thermal stability and fairly increases in proton conductivity. In this work we have used K.C.270 nonwoven material consisting of fine polyester fibers and has a thickness of below 110 μm.     

Crystal Structure Investigations of Inclusion Complexes Between β-cyclodextrin and Alkyl(aqua)cobaloximes (Alkyl=Butyl,Hexyl and Cyclohexyl)

The crystal and molecular structures of alkylcobaloxime/ g -cyclodextrin ( g -CD) inclusion complexes: butyl(aqua)cobaloxime/ g -CD ( 1 ). hexyl(aqua)cobaloxime/ g -CD ( 2 ) and cyclohexyl(aqua)cobaloxime/ g -CD ( 3 ) were determined by X-ray diffraction analyses. Crystal data for 1 14H 2 O: P 2 1 2 1 2 1 , a =15.1335(3), b =18.9630(2), c =28.1545(5) Å, Z =4; 2 12H 2 O: P 2 1 2 1 2 1 , a =15.1135(4), b =19.1477(5), c =28.2715(7) Å, Z =4; 3 10H 2 O: P 2 1 2 1 2 1 , a =15.6898(2), b =16.9094(2), c =28.9762(2) Å, Z =4. The structural and conformational comparisons for the three g -CD inclusion complexes with their guest molecules as well as other CD inclusion analogs are discussed.     

Recognition of anions and monocarboxylic acids by a fluorescent guanidine-based receptor

A guanidine-based fluorescent receptor has been synthesised to study its binding behaviour towards anions (F^? , Cl^? , Br^? , I^?  and AcO^? ). The two donor N–H bonds of the receptor do not point in the same direction; rather, one N–H bond is intramolecularly hydrogen-bonded with the carbonyl oxygen atom. The nature of the donor–acceptor (DA) arrangement induces moderate binding properties. The binding behaviour towards monocarboxylic acids (benzoic acid and phenylacetic acid) is also compared. The binding behaviour of receptor 1 towards the F^?  anion is higher among the anions studied, whereas in the case of monocarboxylic acid, the binding constant with phenylacetic acid is higher than benzoic acid.     

Diethyl 1-(p-fluoro­phenyl)-5-oxo-3-(2-thienyl)­pyrrolidine-2,2-di­carboxyl­ate

In the title compound, C₂₀H₂₀FNO₅S, the pyrrolidine ring adopts an envelope conformation. The fluoro­phenyl and thio­phene rings are individually planar. The molecular and crystal structures are stabilized by intra- and intermolecular C—H⋯O interactions.     

Syntheses,crystal structures and spectroscopic properties of the novel complexes [M(MOBPT)*2 (H2O)2](ClO4)2 · 4H2O (M = CoII and NiII)

The novel cobalt(II) and nickel(II) complexes with 4-(p-methoxyphenyl)-3,5-bis(pyridin-2-yl)-1,2,4-triazole (MOBPT) have been synthesized and their molecular structures determined by X-ray analysis, i.r. and by ESI-MS spectroscopy. The metal atom is in a distorted octahedral environment. Two bidentate chelating ligands (MOBPT) coordinate to the metal center equatorially and two water molecules coordinate axially. Each MOBPT entity coordinates via one triazole nitrogen and one pyridine nitrogen atom. Magnetic measurements show that the complexes are high-spin species in the 75–300 K range.     

Facile synthesis of spiroisoquinolines based on photocycloaddition of isoquinoline-1,3,4-trione with oxazoles

Photocycloaddition of isoquinoline-1,3,4-trione and 5-methoxyoxazoles affords spiroisoquinolineoxetanes with high regio- and diastereoselectivity. The spiroisoquinolineoxetanes can be conveniently converted into novel spiroisoquinolineoxazoline derivatives through acid catalyzed sequential reactions.     

An unprecedented 8-fold interpenetrating diamondoid-like coordination polymer containing a Cu+(4)(RCO2)(4) cluster as connecting node

The reaction of Cu(I)(CH(3)CN)(4)BF(4) with 4-pyridylacrylic acid (4-HPYA) affords an unprecedented 8-fold interpenetrating diamondoid-like coordination polymer network [Cu(I)(3)(4-PYA)(2)(H(2)O)(BF(4)) ] (1) with a Cu(+)(4)(CO(2))(4) cluster as connecting node. The interpenetration in metal coordination polymers is the highest degree ever found within diamondoid nets containing a cluster as connecting note. Its fluorescent property was also reported.     

Synthesis and crystal structure of an imidazolate-bridged dicopper tris(2-aminoethyl)amine complex

The [Cu(tren)(Im)Cu(tren)](ClO4)3·MeCN complex [tren=tris(2-aminoethyl)amine; Im=imidazolate anion] has been synthesized and characterized spectrally. The X-ray crystal structure analysis reveals that the imidazolate anion serves as a bridge to form a noncentrosymmetric dimeric structure in the complex. The co-ordination geometry about each copper(II) ion is a distorted trigonal bipyramid with three primary amine groups of the tren ligand forming the equatorial plane. The tertiary amine group and the imidazolate anion are in the axial positions. This revised version was published online in June 2006 with corrections to the Cover Date.     

Synthesis,crystal structure and two-photon property studies on a series of complexes derived from a novel Schiff base ligand

A new Schiff base ligand derived from S-benzyldithiocarbazate and 4-[N-hydroxy ethyl-N-(methyl)amino]benzaldehyde (HL, where H is a dissociable proton) and its Ni^II, Cu^II, Zn^II and Pd^II complexes were prepared and fully characterized. The structures of HL and Ni(L)₂ were determined by X-ray diffraction analysis, which revealed that the geometry of the Ni^II ion is square-planar with two equivalent Ni=N and Ni=S bonds, and that the two neighboring molecules in two layers have weak contact. The electronic spectra and solution fluorescence of the ligand and the complexes were studied, and the quantum yields of single-photon fluorescence for the compounds were determined. The compounds possess two-photon absorption (t.p.a.) character and the t.p.a. coefficient and t.p.a. cross-section were determined by the Z-scan technique. Especially, the Zn(L)₂complex and the HL ligand exhibit intensive two-photon fluorescence (t.p.f.) at 800 nm laser pulses in the femtosecond regime.