1. Girard-P reagent (acetohydrazide pyridinium chloride) has been found to replace the C-4 amino group of N1-substituted cytosine and cytidylic acids with an acetohydrazidopyridinium residue. The reaction took place at a maximum rate at pH 4.2 and followed a pseudo first-order rate.2. The reacti...

1.1. Rat-thymus cells were incubate with [14C6]glucose. Ribose and deoxyribose moieties bound to the different bases of nucleic acids were isolated and the incorporation of 14C into these sugars was determined.2.2. Among the ribose moieties, those bound to adenine and guanine had the highest spe...

Isoniazid the tuberculostatic drug, was shown to react with ribonucleic acids under mildly acidic conditions. When yeast tRNA was treated with 10% aqueous solution of isoniazid at pH 4.2 and 37°, an extensive derivatization of cytosine residues was observed. The characteristics of this reaction...

In order to study the long-range radical transfer in the Escherichia coli ribonucleotide reductase (RNR), caged cytidine 5′-diphosphate (CDP) 1 was synthesized, which contains the photolabile (7-diethylaminocoumarin-4-yl)methyl moiety. The caged CDP 1 triggers the release of CDP when irradiated...

The emergence of drug-resistant strains of Mycobacterium tuberculosis, the causative agent of tuberculosis, has exacerbated the treatment and control of this disease. Cytidine deaminase (CDA) is a pyrimidine salvage pathway enzyme that recycles cytidine and 2′-deoxycytidine for uridine and 2′-...

The stereoselectivities of recombinant human deoxycytidine kinase (EC 2. 7.1.74) (dCK) and of recombinant human cytidine deaminase (EC 3.5.4.5) (CDA) were investigated with respect to a series of cytidine analogs, most of them having the unnatural l-stereochemistry. The enantioselectivity of dCK...

A series of new 2′-deoxy-2′-β-fluoro-4′-azido-β-d-arabinofuranosyl cytidine derivatives bearing heteroatom-containing N4-substituents were designed and synthesized. Antiviral screening in HepG2.2.15 cells identified three analogs (1a, 1d & 1g) with good anti-HBV activity and low cytotoxicty...

In the present work the effect of a mutation on tyrosine 33 residue (Y33G) of human cytidine deaminase (CDA) was investigated with regard to protein solubility and specific activity. Osmolytes and CDA ligands were used to increase the yield and the specific activity of the protein. The mutant en...

Human cytidine deaminase is an enzyme of the pyrimidine salvage pathways that metabolizes several cytosine nucleoside analogs used as prodrugs in chemotherapy. We carried out a characterization of the cytidine deaminase 79A>C and 208G>A Single Nucleotide Polymorphisms, in order to highlight thei...

The adsorption and interfacial orientations of cytidine sulphate were studied by out-of-phase ac voltammetry. The adsorption equilibrium and its attainment have been investigated as a function of various parameters such as pH, adsorption potential, adsorption time, temperature and the bulk conce...

The synthesis and spectral properties of modified cytidine analogues are described here. To confer fluorescent properties, the cytidine fluorophore was extended by a cinnamyl moiety at the cytidine 5-position, (analogues 1a–c), or extended by a phenyl-imidazolo ring, (analogues 3a–d). Those co...

Neutral platinum(II) complexes with two bidentate 1-((tetrazolid-5-yl)methyl)-3-alkylimidazolin-2-ylidene ligands (alkyl = methyl, n-butyl) have been synthesized and characterized to investigate the electronic and steric effects of tetrazolidyl NHC ligands. Solid state structures of the complexe...

In the present work, an experimental study is presented aimed at assessing the chronic toxicity of three imidazole-based ionic liquids, i.e. imidazole (IM), 1-methylimidazole (1MIM), 1-ethyl-3-methyl-imidazolium chloride (1E3MIM), and 1-butyl-3-methyl-imidazolium chloride (1B3MIM), generally con...

The effects of cyanide on enzymatic activity and absorption spectra in the visible and mid-IR (2150–1850 cm−1) regions were characterized for purified HydSL hydrogenase from the purple sulfur bacterium Thiocapsa (T.) roseopersicina BBS. Prolonged incubation (over hours) of T. roseopersicina hyd...

Several manganese(III) porphyrins showed significantly increased turnover-numbers for the catalytic epoxidation of styrene upon addition of bulky Lewis acids such as ZnTPP and MgTPP (TPP=tetraphenylporphyrin). Catalytic enhancement of two- to four-fold, depending on the additive, was observed wi...

In this paper we report the oxidation and oligomerization of ethyl linoleate (EL), a model compound for alkyd resins, under the influence of iron-2-ethylhexanoate (Fe-eh) in combination with ascorbic acid 6-palmitate (AsA6p) at different AsA6p/Fe-eh molar ratios (0/1–4/1). Reactions were studie...

A method for the synthesis of 1-amino-2,4-dichloroanthraquinone of very high purity is described, involving chlorination with gaseous chlorine of 1-aminoanthraquinone in boiling aliphatic organic solvents.The 1-amino-2,4-dichloroanthraquinone thus obtained was used in the synthesis of blue acid ...

A photorheologically reversible micelle composed of polymerizable cationic surfactant n-cetyl dimethylallyl ammonium chloride (CDAAC) and trans-4-phenylazo benzoic acid (trans-ACA) was prepared. The effects of molar ratio of CDAAC/trans-ACA, time of UV and visible light irradiation and temperatu...

Herein, a photo-responsive molecule, 2-phenylazopyridine (PAP) was incorporated as a guest into a porous crystalline metal-organic framework (MOF), MOF-5. Detail experimental studies like elemental analysis, PXRD measurements, IR spectroscopy have been performed to confirm the successful embedme...

The molecular and solid-state structures of methyl [2-(acridin-9-ylimino)-3-(tert-butylamino)-4-oxothiazolidin-5-ylidene]acetate (4) were determined by X-ray diffraction, 1H NMR, 13C NMR, CI mass spectroscopy and B3LYP calculations using the basis sets 6-31G(d, p), 6-311+G(d, p) and 6-311++G(2d,...