A Novel Fluorescence Probe 9-(4-(1,2-diamine)benzeneN^1-phenyl)acridine for Nitric Oxide Determination

A novel fluorescent probe 9-（4-（1,2-diamine）benzene-N1-phenyl）acridine（DABPA） was synthesized for the detection of nitric oxide（NO） and characterized by IR, 1H-NMR and EI-MS spectroscopy. Based on a photoelectron transfer mechanism, the fl uorescence intensities of DABPA were investigated with the different concentrations of NO. Under the optimal experimental conditions, the fl uorescence intensity of DABPA had a good linear relationship（R2=0.9977） with NO concentration in the range from 1×10-7 to 1.5×10-6 mol/L with a detection limit of 1×10-8 mol/L. The cytotoxicity induced by DABPA was evaluated by the MTT（3-（4,5-dimethylthiazol-2-yl）-2,5diphenyl tetrazolium bromide） assay for biological application. Furthermore, the probe DABPA had also been successfully applied to real-time image NO produced in PC12 cells in the presence of L-arginine.

Effect of protease inhibitor from Agaricus bisporus on glucose uptake and oxidative stress in 3T3-L1 adipocytes

Objective:To explore the effect of the protease inhibitor from Agaricus bisporus(J.E.Lange)Imbach(AbPI)on glucose uptake and oxidative stress in 3 T3-L1 adipocytes.Methods:Adipocytes were differentiated and stained with OilRed-O staining to confirm adipogenesis.The toxic/protective effect of AbPI on the adipocytes was determined by MTT assay,intracellular reactive oxygen species generation through flow cytometry,and morphologically through confocal microscopy using propidium iodide,4,6-diamino-2-phenylindol dihydrochloride,and 2’,7’-dichlorofluorescein diacetate dyes.The uptake of fluorescent glucose analog,2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose by adipocytes was also studied through confocal microscopy.Results:MTT assay showed that the cell survival rate was(28.00±3.00)%,(92.33±2.60)%,and(71.34±2.10)%in the presence of 2 mM H2O2,AbPI alone,and AbPI and H2O2 both,respectively,in comparison to the control.Oil-Red-O staining indicated that Ab PI enhanced adipogenesis.AbPI stimulated the glucose uptake by adipocytes similar to the drug rosiglitazone,and showed insulinsensitizing effect in the presence of insulin,but failed to stimulate the uptake in the absence of insulin.Intracellular reactive oxygen species generation was reduced in differentiating adipocytes upon Ab PI treatment.Confocal microscopy showed that the damaged cell population rose to 3.50%,117.84%,and 261.50%in the presence of Ab PI alone,AbPI with H2O2,and H2O2 alone,respectively.Conclusions:The protease inhibitor enhances glucose uptake by adipocytes and exhibits a cytoprotective effect on them.

Effect of Temperature on the Reaction of 2-(N-acetylamine)-3-(3,5-di-<i>tert</i>-butyl-4-hydroxyphenyl)-propionic Acid with Oxygen in an Alkaline Condition

Results of oxidation 2-(N-acetylamine)-3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid oxygen depend on temperature. At 55℃?- 60℃, 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa is formed. The constitution is based on dates of spectrums 1Н and 13С NMR. At 95℃?- 97℃, mixtures of 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa and of 6,8-di-tert-butyl-3-(N-acetylamine)spiro(4,5)deca-1-oxa-5,8-dien-2,7-dione are produced. Structures are calculated by the method of Hartrii-Foka. Values of enthalpies and of entropies allow to assume dynamic isomerism.

Cerium(Ⅳ)ammonium nitrate(CAN)-mediated regioselective synthesis and anticancer activity of 6-substituted 5,8-dimethoxy-1,4-naphthoquinone

6-Substituted 5,8-O-dimethyl-1,4-naphthoquinones（6-DMNQ）,the promising anticancer scaffolds,were selectively generated by oxidative demethylation of 2-substituted 1,4,5,8-tetramethoxynaphthalenes with CAN in EtOAc/H2O in comparatively high yields.An interesting finding was that apart from the reported electron-withdrawing effects of substituents on position 2 of naphthalene ring,regioselective synthesis of 6-DMNQ was largely dependent on the steric effects in CAN-mediated oxidation.The selective cytotoxicities of 6-DMNQ from the in vitro cell-based assays were exhibited between the cancer cells and normal cells.Moreover,most of sulfur-containing 6-DMNQ derivatives displayed better anticancer activities than the corresponding oxygen-containing ones,which could provide an available strategy for the design of 6-DMNQ derivatives as potential anticancer agents.