Limonoids are the important secondary metabolites in the citrus. In this study, the accumulation of limonoids at different fruit developmental stages and distribution among different genotypes, tissues and developmental stages were investigated in 12 pummelo varieties. The large variations on li...

The mechanism of the Mur synthetases of peptidoglycan biosynthesis is thought to involve in each case the successive formation of an acyl phosphate and a tetrahedral intermediate. The existence of the acyl phosphates for the MurC and MurD enzymes from Escherichia coli was firmly established by t...

The aim of this study was to see whether the compound adenosine 5′-tetraphosphate (Ap4) is active in the central nervous system by examining its effect on isolated rat brain synaptic terminals. Ap4 proved to be more resistant to ecto-enzymatic hydrolysis than adenosine triphosphate (ATP), showi...

Homogeneous soluble exopolyphosphatase (EC 3.6.1.11) from yeast Saccharomyces cerevisiae, (scPPX1) behaves as an adenosine 5′-tetraphosphate phosphohydrolase (EC 3.6.1.14). The hydrolysis of adenosine 5′-tetraphosphate (p4A) to ATP and orthophosphate absolutely depends on one of the following ...

SummaryAdenosine 5’-tetraphosphate (Ap4) is a ubiquitous metabolite involved in cell signaling in mammals. Its full physiological significance remains unknown. Here we show that two enzymes committed to NAD biosynthesis, nicotinamide phosphoribosyltransferase (NAMPT) and nicotinate phosphoribos...

Crystals of cholesteryl oleate (C45H78O2) are monoclinic, space group P21, with a = 12.65(3), b = 9.13(3), c = 18.79(5)Å, β = 93.3(3)° and have 2 molecules in the unit cell. The crystal structure has been determined by Patterson and Fourier methods at a resolution dmin = 1.1 Å, using 799 X-r...

The crystallization process in the two-component system of cholesteryl nonanoate and cholesteryl decanoate was studied. The activation energy for the liquid crystals (smectic mesophases) to crystallize as spherulites was found to have a maximum at 60% of the nonanoate and was interpreted as due ...

Self-assembled drug delivery systems (SADDS) are defined as the self-assemblies of amphiphilic prodrugs, integrating prodrugs, molecular self-assembly and nanotechnology for drug targeting and controlled release. Cholesteryl-succinyl didanosine (CSD) and cholesteryl-adipoyl didanosine (CAD) nano...

In order to study electronic and structural properties of a family of cholesterol esters, the cholesteryl alkanoates, we have performed a semi-empirical quantum calculation. From some previous works, we have generalized the existence of three types of configuration obtained for the cholesteryl a...

To investigate the influence of lipid unsaturation and neutral lipid on the maturation of high density lipoproteins, the discoidal complexes of apoA-I, phosphatidylcholine and cholesteryl ester (CE) were prepared. Saturated dipalmitoylphosphatidylcholine (DPPC) and unsaturated palmitoyllinoleoyl...

The properties of six chiral non-symmetric dimers belonging to the family of (S)-(benzylidene-4′-substitutedaniline)-2″-methylbutyl-4‴-(4″″-phenyloxy)benzoate-oxy)hexanoates are described. The terminal substituents on the 4-benzylidene-4′-substituted fragment are H, Cl, Br, I, CH3 and C2H5....

The objective of this research was to investigate the effect of temperature, pressure, initiator concentration and agitation rate, in ethylene-vinyl acetate emulsion copolymerization, on copolymer composition. The inline React-IR ATR system was used to monitor the reaction as well as to determin...

H-bonding organocatalysis using (thio)urea/amine achieved massive success. H-bonding binding with Brønsted acid catalysis, especially in polymerizations, was scarcely explored. Here we disclosed 1,3-bis-(3,5-bis(trifluoromethyl)phenyl)thiourea (TU) as hydrogen bond donor (HBD), combined with tri...

Synthesis of [3α-3H]7-dehydrocholesterol is described via protection of the 5,7-diene system in 7-dehydrocholesterol as the Diels-Alder adduct with 4-phenyl-1,2,4-triazoline-3,5-dione followed by oxidation of the hydroxyl group to give the 3-oxo adduct. Reduction of the keto adduct with [3H]sod...

Tissue accumulation of 7-dehydrocholesterol (7DHC) is a hallmark of Smith-Lemli-Opitz Syndrome (SLOS), a human inborn error of the cholesterol (CHOL) synthesis pathway. Retinal 7DHC-derived oxysterol formation occurs in the AY9944-induced rat model of SLOS, which exhibits a retinal degeneration ...

The presence of cholesterol, 7-dehydrocholesterol, cholecalciferol (vitamin D3) and its hydroxylated metabolites, 25-hydroxycholecalciferol (25-OH D3) and 1α,25-dihydroxycholecalciferol (1α,25-diOH D3), was demonstrated in cell cultures derived from sterile leaves of Solanum malacoxylon. When ...

SummarySmith-Lemli-Opitz syndrome is a frequently occurring autosomal recessive developmental disorder characterized by facial dysmorphisms, mental retardation, and multiple congenital anomalies. Biochemically, the disorder is caused by deficient activity of 7-dehydrocholesterol reductase, which...

Secodione 3 and hemiacetal 4 from ozonolysis of peroxide 2 were obtained. A tentative mechanism of their formation is proposed.

A highly efficient and improved method for the preparation of stereoisomeric 4α- and 4β-hydroxy-7-dehydrocholesterol has been developed. These oxysterols are atypical precursors of cholesterol found to be present in increased concentrations in brain, liver, and serum of animals treated with AY...

Ultraviolet radiation is the main cause of skin cancers, and melanoma is the most serious form of tumor. There is no therapy for advanced-stage melanoma and its metastasis because of their high resistance to various anticancer therapies. Human skin is an important metabolic organ in which occurs...