The title complex, [Ni(2)(C(6)H(2)N(3)O(7))(2)(C(10)H(20)N(4)O(4))], contains a centrosymmetric binuclear unit in which the oxamide ligand (located on a centre of symmetry) acts in a bis--tetra-dentate fashion and the picrate anion binds to nickel(II) in a bidentate mode. The Ni(II) atom displays a distorted octa-hedral coordination with axial elongation. The binuclear mol-ecules are linked by ...

A "stopped-flow" method for the kinetic Jaffé determination of creatinine was developed, with the use of a computer-controlled continuous-flow system. Simplex optimization was used to find conditions of hydroxide and picrate giving maximum sensitivity for creatinine. We used a modified central composite experimental design to evaluate creatinine sensitivity and albumin, glucose, and acetone int...

A crystal structure redetermination of the L-tryptophan picrate crystal previously studied by Ishida et al. (Chem. Pharm. Bull. 41 (1993) 433-438) showed that it comprises L-tryptophan L-tryptophanium dimeric cation, one picrate anion and picric acid. The O⋯O distance of the O-H⋯O hydrogen bond in the dimeric cation is equal to 2.470(6) Å. The infrared spectrum of the crystal was registered and...

The title compound, C(13)H(19)N(2)O(2) (+)·C(6)H(2)N(3)O(7) (-), is a salt obtained by cocrystallization of 4-[(4-methyl-piperazin-1-yl)meth-yl]benzoic acid and picric acid. The cations adopt an 'L-shaped' conformation and are linked into chains along [010] by O-H⋯N hydrogen bonds. The NH group of each piperazinium ring forms a hydrogen bond to the phenolate O atom of a picrate anion, and the p...

A colorimetric peroxidase-coupled procedure for determination of creatinine in human serum and urine is described. A 30-s sample pre-treatment with bilirubin oxidase eliminates interference from endogenous bilirubin. The 4-aminoantipyrine-2-hydroxy-3,5-dichlorobenzenesulfonate chromogen system of this method is about fourfold more sensitive than current procedures that involve monitoring NAD(P)...

two n4-type schiff base ligands named n,n'-bis(2-pyridylmethylidene)-1,2-diiminoethane (l1) and n,n'-bis(2-pyridylmethylidene)-1,3-diiminopropane (l2) have been synthesized by the reaction of pyridine-2-carbaldehyde with ethylenediamine and propylenediamine, respectively. the binding abilities of l1 and l2 in dichloromethane towards cu2+, cd2+, co2+, ni2+, zn2+ and pb2+ ions were evaluated by p...

In the title compound, C(5)H(7)N(2) (+)·C(6)H(2)N(3)O(7) (-), there are two crystallographically independent cations and anions (A and B) in the asymmetric unit. In both picrate anions, one of the nitro groups lies in the plane of the benzene ring [r.m.s. deviations = 0.014 (2) and 0.014 (2) Å for anions A and B, respectively] and the other two are twisted away by 39.0 (2) and 18.8 (2)° in A, a...

In the title salt, C6H13N2O(+)·C6H2N3O7 (-) (systematic name: 4-acetyl-piperazin-1-ium 2,4,6-tri-nitro-phenolate), the piperazin-1-ium ring has a slightly distorted chair conformation. In the picrate anion, the mean planes of the two o-NO2 and p-NO2 groups are twisted with respect to the benzene ring by 15.0 (2), 68.9 (4) and 4.4 (3)°, respectively. In the crystal, N-H⋯O hydrogen bonds are obse...

In the crystal structure of the title compound, C6H8N3O2 (+)·C6H2N3O7 (-)·H2O, N-H⋯O and O-H⋯O hydrogen bonds link the components into a two-dimensional network parallel to (010). In addition, there are pairs of weak inversion-related C-H⋯O hydrogen bonds within the two-dimensional network. The three nitro groups are twisted by 1.6 (3), 7.8 (3) and 12.1 (3)° from the ring plane in the anion, wh...