Measurement of Orotic Acid in Urine by Supercritical Fluid Chromatography

This work presents a simple, rapid and reliable supercritical fluid chromatography (SFC) method for a sensitive measurement of orotic acid in human urine. The samples were diluted with deionized water and analyzed directly without any pretreatment.

Synthesis, Molecular Spectroscopy, Computational, Thermal Analysis and Biological Activity of Some Orotic Acid Complexes

Binary orotic acid metal complexes of Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), and two mixed metals complexes of (Co(II), Ni(II)) and (Ni(II), Cu(II)) were synthesized and characterized by elemental analysis, IR, electronic spectra, magnetic susceptibility, and ESR spectra. The Analysis proved that the ligand has different coordination modes and the complexes were of octahedral, tetrahedral, and trigonal bipyramidal geometries. Molecular modeling techniques and quantum chemical methods have been performed for orotic acid to calculate charges, bond lengths, bond angles, dihedral angles, electronegativity (χ), chemical potential (μ), global hardness (η), softness (σ) and the electrophilicity index (ω). The thermal decomposition of the complexes was monitored by TGA, DTA, and DSC techniques under the N2 atmosphere. The thermal decomposition mechanisms of the complexes were suggested. The biological activity of orotic acid and some of the complexes are tested against antibacterial and antifungal organisms.

Orotic Acid, More Than Just an Intermediate of Pyrimidine de novo Synthesis

It is timely to consider the many facets of the small molecule orotic acid （OA）, which is well-known as an essential intermediate of pyrimidine de novo synthesis. In addition, it can be taken up by erythrocytes and hepatocytes for conversion into uridine and for use in the pyrimidine recycling pathway. We discuss the link between dietary orotate and fatty liver in rats, and the potential for the alleviation of neonatal hyperbilirubinaemia. We address the development of orotate derivatives for application as anti-pyrimidine drugs, and of com- plexes with metal ions and organic cations to assist therapies of metabolic syndromes. Recent genetic data link human Miller syndrome to defects in the dihydroorotate dehydrogenase （DHODH） gene, hence to depleted orotate production. Another defect in pyrimidine biosynthesis, the orotic aciduria arising in humans and cattle with a deficiency of UMP synthase （UMPS）, has different symptoms. More recent work leads us to conclude that OA may have a role in regulating gene transcription.

Preparation and application of a novel orotic acid chelating resin for removal of Cu(Ⅱ) in aqueous solutions

A novel chelating resin OABA,capable of removing Cu（Ⅱ） from aqueous solution,was synthesized via the reaction of macroporous chloromethylated PS-DVB copolymer beads with orotic acid.The elemental analysis（EA）,Fourier transform infrared spectroscopy（FT-IR）,and scanning electron microscopy microscope-energy dispersive X-ray spectroscopy（SEM-EDS） were used in the characterization of the synthesized chelating resin.Multiple,static batch adsorption experiments were conducted at different initial concentrations and temperatures.OABA showed good adsorption capacity for Cu（Ⅱ） and the equilibrium data could be well matched with the Freundlich isotherm model.Coexisting sodium chloride and calcium chloride in solutions favored the Cu（Ⅱ） adsorption.Moreover,the desorption process of Cu（Ⅱ） was tested and over 90%regeneration efficiency for the spent OABA was achieved at ammonia concentrations ranging from 1.0%to 2.0%.The results suggested that OABA would be a potential alternative adsorbent for Cu（Ⅱ）,even with other heavy metal ion treatments of wastewater.

Hydrothermal Synthesis and Crystal Structure of Lanthanum Orotate Supermolecule with A Honeycomb Structure Constructed from Mononuclear Molecules via Hydrogen Bonds

A new complex of lanthanum orotate [La（C5H3N2O4）2（OH）（H2O）6 ]·2（C5H4N2O4）·9H2O was synthesized using a hydrothermal method. The crystal structure was determined with help of single crystal X-ray diffraction analysis. The complex crystallized in orthorhombic system, Cmc2（1） space group. In the complex, the center lanthanum （Ⅲ） ion was nine-coordinated with coordination geometry of a distorted monocapped square antiprism, in which two of the nine coordinated oxygen atoms were from two orotate ligands in a monodentate mode, one oxygen atom from a hydroxyl, and the others from six coordinated water molecules. The mononuclear complex [La（C5H3N2O4）2（OH）（H2O）6 ]·2（C5H4N2O4）·9H2O was linked through the hydrogen bonds into an infinite supermolecular honeycomb structure.

Synthesis and Crystal Structure of [Ni(C_5H_2N_2O_4)(2,2'bipy)(H_2O)_2]·H_2O

The crystal structure of [Ni(C5H2N2O4)(2, 2?bipy)(H2O)2]?H2O 1 has been determined by X-ray diffraction. Crystal data: triclinic system, space group P with a = 7.9424(3), b = 9.9417(3), c = 12.1867(3) ? a = 84.771(1), b = 77.375(2), g = 68.993(2)? C15H18N4O8Ni, Mr = 440.7, V = 876.16(5) 3, Z = 2, Dc = 1.672 g/cm3, F(000) = 456, m(MoKa) = 1.162 mm-1, the final R = 0.0464 and wR = 0.1055 for 3026 observed reflections with I > 2s(I). In the title compound, the nickel ion is coordinated by a nitrogen atom and an oxygen atom from the orotate ligand, two nitrogen atoms from 2, 2?bipy and two oxygen atoms from the coordinated water molecules in a distorted octahedral geometry. The presence of intermolecular hydrogen bonding and p-p stacking interaction of aromatic rings from 2, 2?bipy results in a 3D structure.