Crystal structure, raman and 57Fe mo¨ssbauer spectra of the FeII complex of iso-orotic acid

Synthesis, Structure and Impact of 5-Aminoorotic Acid and Its Complexes with Lanthanum(III) and Gallium(III) on the Activity of Xanthine Oxidase

The superoxide radical ion is involved in numerous physiological processes, associated with both health and pathology. Its participation in cancer onset and progression is well documented. Lanthanum(III) and gallium(III) are cations that are known to possess anticancer properties. Their coordination complexes are being investigated by the scientific community in the search for novel oncological disease remedies. Their complexes with 5-aminoorotic acid suppress superoxide, derived enzymatically from xanthine/xanthine oxidase (X/XO). It seems that they, to differing extents, impact the enzyme, or the substrate, or both. The present study closely examines their chemical structure by way of modern methods-IR, Raman, and 1H NMR spectroscopy. Their superoxide-scavenging behavior in the presence of a non-enzymatic source (potassium superoxide) is compared to that in the presence of an enzymatic source (X/XO). Enzymatic activity of XO, defined in terms of the production of uric acid, seems to be impacted by both complexes and the pure ligand in a concentration-dependent manner. In order to better relate the compounds' chemical characteristics to XO inhibition, they were docked in silico to XO. A molecular docking assay provided further proof that 5-aminoorotic acid and its complexes with lanthanum(III) and gallium(III) very probably suppress superoxide production via XO inhibition.

Theoretical and Experimental Vibrational Characterization of Biologically Active Nd(III) Complex

The neodymium(III) complex of orotic acid (HOA) was synthesized and its structure determined by means of analytical and spectral analyses. Detailed vibrational analysis of HOA, sodium salt of HOA, and Nd(III)–OA systems based on both the calculated and experimental spectra confirmed the suggested metal–ligand binding mode. Significant differences in the IR and Raman spectra of the complex were observed as compared to the spectra of the ligand. The calculated vibrational wavenumbers, including IR intensities and Raman scattering activities, for the ligand and its Nd(III) complex were in good agreement with the experimental data. The vibrational analysis performed for the studied species, orotic acid, sodium salt of orotic acid, and its Nd(III) complex helped to explain the vibrational behaviour of the ligand’s vibrational modes, sensitive to interaction with Nd(III). In this paper we also report preliminary results about the cytotoxicity of the investigated compounds. The cytotoxic effects of the ligand and its Nd(III) complex were determined using the MTT method on different tumour cell lines. The screening performed revealed that the tested compounds exerted cytotoxic activity upon the evaluated cell lines.

Multicomponent solids of uracil derivatives – orotic and isoorotic acids

Cocrystallization of two multifunctional structural isomers viz. orotic and isoorotic acids was explored with a series of amine and pyridine-based coformers.

Synthesis, structural characterization and antimicrobial activity evaluation of metal complexes of sparfloxacin

The synthesis and characterization of binary Cu(II)- (1), Co(II)- (2), Ni(II)- (3), Mn(II)- (4), Cr(III)- (5), Fe(III)- (6), La(III)- (7), UO(2)(VI)- (8) complexes with sparfloxacin (HL(1)) and ternary Cu(II)- (9), Co(II)- (10), Ni(II)- (11), Mn(II)- (12), Cr(III)- (13), Fe(III)- (14), La(III)- (15), UO(2)(VI)- (16) complexes with sparfloxacin (HL(1)) and DL-alanine (H(2)L(2)) complexes are reported using elemental analysis, molar conductance, magnetic susceptibility, IR, UV-Vis, thermal analysis and (1)H-NMR spectral studies. The molar conductance measurements of all the complexes in DMF solution correspond to non-electrolytic nature. All complexes were of the high-spin type and found to have six-coordinate octahedral geometry except the Cu(II) complexes which were four coordinate, square planar and U- and La-atoms in the uranyl and lanthanide have a pentagonal bipyramidal coordination sphere. The antimicrobial activity of these complexes has been screened against two gram-positive and two gram-negative bacteria. Antifungal activity against two different fungi has been evaluated and compared with reference drug sparfloxacin. All the binary and ternary complexes showed remarkable potential antimicrobial activity higher than the recommended standard agents. Ni(II)- and Mn(II) complexes exhibited higher potency as compared to the parent drug against gram-negative bacteria.

(4-Oxido-2-oxo-1,2-dihydro-pyrimidine-5-carboxyl-ato-κO,O)(4-oxido-2-oxo-1,2-dihydro-pyrimidin-3-ium-5-carboxyl-ato-κO,O)bis-(1,10-phenanthroline-κN,N')gadolinium(III) dihydrate

The title compound, [Gd(C(5)H(2)N(2)O(4))(C(5)H(3)N(2)O(4))(C(12)H(8)N(2))(2)]·2H(2)O, was obtained from a solvothermal reaction of 2,4-dihydroxy-pyrimidine-5-carboxylic acid (H(3)iso), GdCl(3)·6H(2)O and 1,10-phenanthroline (phen). The Gd(III) ion is located on a twofold rotation axis and is coordinated by four N atoms from two chelating phen ligands and four O atoms (5-carboxyl-ate and 4-oxido O atoms) from H(2)iso(-) and Hiso(2-) ligands. The mol-ecules are linked into a three-dimensional network by N-H⋯O, N-H⋯N and O-H⋯O hydrogen bonds. The H atom involved in an N-H⋯N hydrogen bond is disordered around a twofold rotation axis with half occupancy.

New Lanthanum (III) Complex – Synthesis, Characterization, and Cytotoxic Activity

The complex of lanthanum (III) was synthesized reacting the respective inorganic salt with 5-aminoorotic acid in amounts equal to the metal:ligand molar ratio of 1:3. The complex was prepared by adding an aqueous solution of lanthanum (III) nitrate to an aqueous solution of the ligand, subsequently raising the pH of the mixture gradually to approx. 5.0 through addition of a dilute solution of sodium hydroxide. The structure of the final complex was determined by means of spectral data (IR, Raman,( 1)H-NMR) and elemental analysis. Significant differences in the IR spectrum of the complex were observed as compared to the spectrum of the ligand. A comparative analysis of the Raman spectrum of the complex with that of the free 5-aminoorotic acid allowed a straightforward assignment of the vibrations of the ligand groups involved in coordination. The ligand and the complex were tested for the cytotoxic activities on the chronic myeloid leukemia derived K-562, overexpressing the BCR-ABL fusion protein and the non-Hodgkin lymphoma derived DOHH-2, characterized by a re-expression of the anti-apoptotic protein bcl-2 cell lines. The results obtained indicate that the tested compounds exerted a considerable cytotoxic activity upon the evaluated cell lines in a concentration-dependent matter, which enabled the construction of dose-response curves and the calculation of the corresponding IC(50 )values. The inorganic salt exerted a very weak cytotoxic effect on these cells, which is in contrast to the lanthanum (III) complex.

The influence of metals on the electronic system of biologically important ligands. Spectroscopic study of benzoates, salicylates, nicotinates and isoorotates. Review

This paper reviews the results of the intense experimental and theoretical studies on the influence of selected metals on the electronic system of biologically important molecules such as benzoic, 2-hydroxybenzoic and 3-pyridine carboxylic acids as well as 5-carboxyuracil. The research involved following techniques: infrared (FT-IR), Raman (FT-Raman), FT-IR Ar matrix, electronic absorption spectroscopy (UV/visible), nuclear magnetic resonance ((1)H, (13)C, (15)N, (17)O NMR), X-ray and quantum mechanical calculations. The influence of metals on the electronic system was examined through comparison of the changes in so called "logical series". The exemplary series are: Li-->Na-->K-->Rb-->Cs, Na(I)-->Ca(II)-->La(III)-->Th(IV); Na(I)-->Mg(II)-->Al(III) or long series of La(III) and fourteen lanthanides La(III)-->Ce(III)-->Lu(III). The correlation between the perturbation of the electronic system of ligands and the position of metals in the periodic table was found. The influence of the carboxylic anion structure and the effect of hydration on the perturbation of the electronic system of molecule were also discussed. The partial explanation in what way metals disturb and stabilize electronic system of studied ligands was done. It is necessary to carry out the physico-chemical studies of benzoates, salicylates, 3-pyridine carboxylates and isoorotates in order to understand the nature of the interactions of these compounds with their biological targets (e.g., receptors in the cell or important cell components). The results of this study make possible to predict some properties of a molecule, such as its reactivity, durability of complex compounds, and kinship to enzymes.

Vibrational analysis and spectra of orotic acid

The IR and Raman spectra of polycrystalline anhydrous orotic acid and its N1, N3, and O12 trideuterated isotopomer are recorded in the 4000-40 cm(-1) spectral interval as part of a series of vibrational analyses of nucleosides, nucleotides, and related compounds carried out in our laboratory. The frequencies of the fundamental transitions and the potential energy distributions of the 39 normal modes of orotic acid and its isotopomer are calculated by an ab initio density functional theory Becke3P86/6-311G** treatment. Assignments of the vibrational modes are proposed that consider the results of these calculations and the observed spectra. The results of the ab initio treatment are related to crystallographic and spectral data, and they are compared with previous assignments for similar molecules.

Characterization of bis(isoorotato)diaquamagnesium(II) dihydrate: a potentially useful complex for magnesium supplementation

The synthesis and crystal structure of a new Mg(II) complex of stoichiometry [Mg(isoor)2(H2O)2].2H2O, where isoor is the monoanion of 5-carboxyuracil (isoorotic acid), are reported. The structure, solved by single-crystal X-ray diffractometry, shows that it crystallizes in the triclinic space group P(-1) with Z = 1. The electronic, IR and Raman spectra of the complex are briefly discussed. Its thermal behavior was also investigated by means of thermal gravimetry (TG) and differential thermal analysis (DTA) measurements in an oxygen atmosphere. Dissolution studies support the usefulness of the compound for magnesium supplementation.