Two new copper(II) complexes, [Cu2(3-bpfp)(2,6-PDA)2(H2O)2] (1) and [Cu(4-bpfp)0.5 (glu)]·H2O (2), have been hydrothermally synthesized by self-assembly of isomeric bis(pyridylformyl)piperazine ligands [3-bpfp = bis(3-pyridylformyl)piperazine, 4-bpfp = bis(4pyridylformyl)piperazine], rigid pyridine-2,6-dicarboxylic acid (2,6-H2PDA) or flexible glutaric acid (H2glu), and copper(II) chloride. Sin...

The syntheses and single crystal X-ray analyses of five strapped salicylaldoxime/salicylaldimine based dicopper(ii) receptors utilising a new piperazine linker are described. The complexes form 2 + 2 metallocycles and the molecular structures of all four complexes possess a small internal cavity with the utilisation of a short piperazine linker. The molecular structures of complexes [Cu2(L(4) -...

The structure-activity relationships within a series of penicillins and cephalosporins containing an N(4)-substituted piperazine-2,3-dione moiety in the C(6)/C(7)-beta-side chain are discussed.

In the title compound, C10H20N4O3, the piperazine ring adopts a chair conformation. The mol-ecule adopts an E conformation across the C=N double bond, with the -OH group and the piperazine ring trans to one another. Further, the H atom of the hy-droxy group is directed away from the NH2 group. An intra-molecular N-H⋯O contact occurs involving the NH2 group and the oxime O atom. In the crystal, ...

An efficient and alternative synthetic approach has been developed to prepare various N-(arylethyl)piperazine-2,6-diones from 4-benzenesulfonyliminodiacetic acid and primary amines using carbonyldiimidazole in the presence of a catalytic amount of DMAP at ambient temperature. Piperazine-2,6-diones are successfully transformed to pharmaceutically useful pyridopyrazines or pyrazinoisoquinolines a...

The biodegradation of secondary amines is particularly important due to their propensity for conversion either chemically or microbiologically to N-nitrosamines which are potent carcinogens. In this research, a weak Gram-positive organism was isolated from river and identified as Mycobacterium. This Mycobacterium grows slowly and effectively utilizes piperazine as the sole source of organic, c...

The asymmetric unit of the title inorganic-organic hybrid compound, (C10H16N2O)[CoCl4]·H2O, consists of a tetrahedral [CoCl4](2-) anion, together with a [C10H18N2O](2+) cation and a water mol-ecule. Crystal cohesion is achieved through N-H⋯Cl, O-H⋯Cl and N-H⋯O hydrogen bonds between organic cations, inorganic anions and the water mol-ecules, building up a three-dimensional network.