Chiral crystallization of a zinc(II) complex.

The compound, {6,6'-dimeth-oxy-2,2'-[(4-azaheptane-1,7-di-yl)bis-(nitrilo-meth-an-yl-idyne)]diphenolato}zinc(II) methanol monosolvate, [Zn(CHNO)]·CHOH, at 298 K crystallizes in the ortho-rhom-bic space group P2. The Zn atom is coordinated by a penta-dentate Schiff base ligand in a distorted trigonal-bipyramidal NO geometry. The equatorial plane is formed by the two phenolic O and one amine N atom.

Crystal structure of {2-[({2-[(2-amino-ethyl)amino]-ethyl}imino)-meth-yl]-6-hy-droxy-phenolato-κ(4) N,N',N'',O (1)}(nitrato-κO)copper(II) ethanol 0.25-solvate.

In the crystal structure of the title mononuclear Cu(II) complex, [Cu(C11H16N3O2)(NO3)]·0.25C2H5OH, the complex molecules are linked by N-H⋯O and O-H⋯O hydrogen bonds, forming a dimer with an approximate non-crystallographic twofold rotation axis of symmetry. In the monomeric unit, the Cu(2+) ion exhibits a distorted square-pyramidal configuration, whereby the anionic [HL](-) Schiff base ligand binds in a tetradentate fashion via the O and the three N atoms which all are approximately coplanar.

Crystal structure of {6,6'-dihy-droxy-2,2'-[imino-bis-(propane-1,3-diyl-nitrilo-methanylyl-idene)]diphenolato-κ(5) O (1),N,N',N'',O (1')}copper(II).

The title compound, [Cu(C20H23N3O4)], crystallizes in the space group Cc with two independent mol-ecules in the asymmetric unit. The Cu(II) atoms are each coordinated by the penta-dentate Schiff base ligand in a distorted trigonal bipyramidal N3O2 geometry. The equatorial plane is formed by the two phenolic O atoms and the amine N atom, while the axial positions are occupied by the two imine N atoms.

A prospective comparison of chronic primary angle-closure glaucoma versus primary open-angle glaucoma in Singapore.

Introduction: To describe the optic disc, visual field and ocular characteristics of a consecutive cohort of Asian patients with chronic primary angle-closure glaucoma (CPACG), and compare them with those having primary open-angle glaucoma (POAG).

Methods: In a prospective comparative case series of new patients with POAG or CPACG in Singapore, all patients underwent visual acuity assessment, slit-lamp examination, tonometry, gonioscopy, refraction, Heidelberg Retina Tomograph (HRT) and Humphrey visual field (HVF) assessment.

Results: 98 patients were enrolled (POAG n = 48; CPACG n = 50).

Quantitative evaluation of anterior chamber parameters using anterior segment optical coherence tomography in primary angle closure mechanisms.

Background: To evaluate different mechanisms of primary angle closure and to quantify anterior chamber parameters in these mechanisms using anterior segment optical coherence tomography in an Asian population.

Design: Hospital-based cross-sectional observational study.

Participants: Forty-eight consecutive patients with primary angle closure glaucoma.

Do shapes and dimensions of scleral flap and sclerostomy influence aqueous outflow in trabeculectomy? A finite element simulation approach.

Background/aim: This study aimed to provide an objective assessment of the effects on the aqueous outflow rate of various geometries of the scleral flap and sclerostomy created in trabeculectomy.

Method: Computer-based models and simulations of this surgical procedure were used to investigate the relative effects of various shapes and dimensions of scleral flap and sclerostomy on the aqueous outflow.

Result: In these computer simulations, increasing scleral flap size was found to be associated with an increase of 48.

Spectral, thermal and electrochemical characterization of novel homo-dinuclear complexes [M2(H3DTPA)(H2O)6]Cl2·xH2O (M=Cr2+, Mn2+, Co2+, Ni2+ or Cu2+).

The title complexes were prepared and characterized employing spectral (FAB-Mass, IR, electronic, (1)H and (13)C NMR), thermal and electrochemical techniques. Analytical and FAB-Mass data suggested a homo-dinuclear stoichiometry. IR and electronic ligand field spectral studies coupled with molecular model computations have indicated a distorted octahedral geometry where the ligand coordinates as a hexadentate dianionic [H(3)DTPA](2-)(H(5)DTPA=diethylenetriaminepentaacetic acid) moiety.

Spectral and physico-chemical investigations of novel homo-dinuclear di-micro2-alkoxo bridged Schiff base complexes: 57Fe Mössbauer parameters of the Fe(III) complex.

Spectral and molecular model computations on homo-dinuclear complexes [M(2)L(2)(H(2)O)(2)Cl(2)] [L=1-(salicylaldeneamino)-3-hydroxypropane, M=Cr(3+), Mn(3+), Fe(3+), Co(3+), Ni(3+) or Cu(3+)] are consistent with a distorted hexa-coordinate geometry. X-band EPR spectral data indicated a rhombic distortion around Cu(II) ion. Magnetic moment and (57)Fe Mössbauer data confirmed a high-spin state electronic configuration (t(2g)(3)e(g)(2), S=5/2) and asymmetric ligand environment around Fe(III) with nuclear transitions Fe(+/-3/2-->1/2) exhibiting Kramer's double degeneracy.

Antimicrobial and SOD activities of novel transition metal complexes of pyridine-2,6-dicarboxylic acid containing 4-picoline as auxiliary ligand.

Ternary complexes are potential models for several mono and polynuclear metal enzymes. The present ternary complexes [Fe(dipic)(4-picoline)]Cl, [M(dipic)(4-picoline)] [M = Co or Ni] and [Cu(dipic)(4-picoline)]n were prepared to exploit as novel antimicrobial agents. The chemical structure and bonding etc.

Synthesis, physico-chemical and spectral investigations of novel homo-bimetallic mixed-ligand complexes: 57Fe Mössbauer parameters of [Fe2(imda)2(H2O)3Cl].

The newly prepared homo-bimetallic complexes [M(2)(imda)(2)(H(2)O)(4)], [M(2)(imda)(2)(Bipy)(2)] (M=Co, Ni or Cu) and [Fe(2)(imda)(2)(H(2)O)(3)Cl] (H(2)imda=iminodiacetic acid and Bipy=2,2'-bipyridine) have been studied employing IR, FAB-mass, (1)H and (13)C NMR, EPR and ligand field spectra, which indicated a high-spin state of metal ion with hexa-coordinate environment. (57)Fe Mössbauer data of the homo-bimetallic complex [Fe(2)(imda)(2)(H(2)O)(3)Cl] confirm a high-spin configuration with Fe (+/-3/2-->1/2) nuclear transitions and the presence of Kramer's double degeneracy. At RT, the spin-spin interactions of the neighbouring nuclei (Fe(3+)-Fe(3+)=S(5/2)-S(5/2)) are anti-ferromagnetically coupled.

Spectroscopic and antimicrobial studies of La3+, Pr3+, Nd3+ and Gd3+ complexes of a dipodal [N,N,N] chelating ligand.

The lanthanide complexes of bis(benzimidazole-2'-yl-methyl)amine (BImz) having molecular formula [M(BImz)X(3)H(2)O]*nH(2)O (M = La, Pr, Nd, or Gd; X = Cl or ClO(4) and n = 1, 2 or 3) were prepared and characterized spectroscopically through IR, (1)H and (13)C NMR, FAB-mass, UV-visible and luminescence spectroscopy. TGA data suggested presence of coordinated and the lattice water. The oscillator strengths of the f-f transitions and the covalency parameters (beta, b(1/2) and delta) have been evaluated from the electronic spectral data.

Postural stability in primary open angle glaucoma.

Background: This study evaluated the visual contribution to postural steadiness in primary open angle glaucoma (POAG), in correlation with the mean deviation (MD) measured through conventional perimetry, and with the Advanced Glaucoma Intervention Study (AGIS) score, which quantifies the extent of losses in the visual field.

Methods: In 35 POAG patients and 21 age-matched normal subjects, the sway of the centre of pressure of the feet, on a firm or foam support, was recorded. The subjects stood on a force-plate with eyes closed, or with one or two eyes open.

Motion perception in glaucoma patients: a review.

Most of the histopathological and psychophysical studies in glaucoma reveal a preferential damage to the magnocellular (M) pathway although a few of them support a damage to the parvocellular (P) pathway as well. In glaucoma, the visual fields are usually evaluated by conventional perimetry. However, it has been demonstrated that 20-40% of ganglion cells are lost before field defects are detected using conventional perimetry.