objective(s):involvement of tyrosinase in the synthesis of melanin and cell signaling pathway has made it an attractive target in the search for therapeutic inhibitors for treatment of different skin hyperpigmentation disorders and melanoma cancers. materials and methods: in the present study, we conducted a comprehensive kinetic analysis to understand the mechanisms of inhibition imposed by 2-...

The interaction of 12 phenoxyacetic acid derivatives with human and serum albumin as well as with egg albumin was studied by charge-transfer reversed-phase (RP) thin-layer chromatography (TLC) and the relative strength of interaction was calculated. Each phenoxyacetic acid derivative interacted with human and bovine serum albumins whereas no interaction was observed with egg albumin. Stepwise r...

A novel strategy for the synthesis of (1-alkanoyloxy-4-alkanoylaminobutylidene)-1,1-bisphosphonic acid derivatives (1a-d) via (1-hydroxy-4-alkanoylaminobutylidene)-1,1-bisphosphonic acid derivatives (2a-d), starting from alendronate has been developed with reasonable 51-77% overall yields. Intermediate products, (1-hydroxy-4-alkanoylaminobutylidene)-1,1-bisphosphonic acid derivatives (2a-d), we...

the silica boron sulfuric acid nanoparticles (sbsans) as an efficient heterogeneous solid acid catalyst with both brønsted and lewis acidic sites catalyzed the preparation of bis-4-hydroxycoumarin derivatives using reaction of aldehydes and 4-hydroxycoumarin under mild and solvent-free condition at room temperature. this new and efficient methodology has advantages in comparison with currently ...

β-cyclodextrin sulfuric acid as a green lewis acid catalyst has been applied for the preparation of bis(indolyl)methanes, tris(indolyl)methanes and 3,3'-diindolyloxindole derivatives by the condensation of indoles with various carbonyl compounds in aqueous media with high to excellent yields.

The aim of this work was to investigate the antioxidant property of honeybee products and their constituents using an ESR method. Antioxidative activity was evaluated as the scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. The DPPH radical scavenging activities, in descending order, were: ethanol extract of Chinese red propolis>ethanol extract of Brazilian green propolis>wat...

In this study, we examined the antitumor activities of isoprenoid derivatives conjugated with substrates of energy metabolism in human hepatoma-bearing athymic mice. Among these compounds, N-geranylpyruvic amide, N-geranyl-p-pyruvaminobenzoic amide, N,N'-digeranylmalic diamide and N,N'-digeranyl-O-acetylmalic diamide had strong antitumor effects. These geranylamine derivatives also inhibited in...

Silica-bonded n-propyldiethylenetriamine sulfamic acid (SBPDSA) was found as an efficient solid acid for the synthesis of coumarins. Coumarin derivatives were obtained via the Pechmann condensation reaction of phenols and β-keto-esters at 80 oC under solvent-free conditions. Also, biscoumarins were obtained via the condensation of aldehydes and 4-hydroxycoumarin in water at reflux conditions. T...

The (3,5-trans)-7-chloro-5-(2-chlorophenyl)-2-oxo-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-acetic acid derivatives 1 have been previously identified as potent squalene synthase inhibitors. A series of (4,1-benzoxazepin-3-ylidene)acetic acid derivatives were synthesized and evaluated for their inhibition of rat and human squalene synthase, and the (E)-isomers were found to exhibit potent inhibitor...

Background: The aim of this study was to evaluate the radioprotective capacity of some novel aminoalkylated dithiocarbamic acid potassium salts against γ-irradiation in mice. Materials and Methods: Eight compounds containing 2-aminoethyl-, 3- aminopropyl-, 4-aminobutyl-, 5-aminopentyl-, 6- aminohexyl-, 7-aminoheptyl-, 8-aminooctyl and 9- aminononyl of dithiocarbamate derivatives were prepared. ...