One-Pot Tandem Coupling Method for the Short-Step Formal Synthesis of Riccardin C.

One-pot reactions reduce reagent amounts and circumvent process treatments, such as work-up and purifications in multi-step reactions. In this study, we achieved the formal total synthesis of riccardin C through a one-pot reaction by simultaneously linking four units through two Sonogashira coupling reactions and one Suzuki coupling reaction, followed by reduction and deprotection. Thus, this one-pot method comprised five steps and did not require the purification of intermediate reaction mixtures, which saves resources, such as reagents and solvents, and expedites the work process.

Practical method for hydroxyl-group protection using strontium metal and readily available silyl chlorides.

We have found that the etherification of silyl-protected secondary alcohols proceeds smoothly in the presence of strontium metal using silyl chloride instead of the expensive, yet more reactive, and commonly used silyl triflate. The reaction occurred almost completely with various alcohols.

Recovering metals from aqueous solutions by biosorption onto phosphorylated dry baker's yeast.

Biosorption is a cost-effective and simple technique for removing heavy metals and rare earth elements from aqueous solution. Here, metals were recovered from aqueous solutions using phosphorylated dry baker's yeast cells. The cells were phosphorylated using cyclo-triphosphate, NaPO.

Yttrium decreases the intracellular Zn2+ concentration in rat thymocytes by attenuating a temperature-sensitive Zn2+ influx.

Yttrium is used in the production of various electronic devices because the alloy it contains enhances or modifies the properties of other elements. In order to study the cytotoxic action of yttrium, the effect of yttrium chloride (YCl(3)) on the intracellular Zn(2+) level was examined in rat thymocytes using a flow cytometer with FluoZin-3-AM and propidium iodide. The application of YCl(3) significantly decreased the intensity of the FluoZin-3 fluorescence, suggesting a decrease in the intracellular Zn(2+) level or quenching of the FluoZin-3 fluorescence by Y(3+).

Some characteristics of membrane Cd²+ transport in rat thymocytes: an analysis using Fluo-3.

Although cadmium-induced apoptosis of lymphocytes is one of common features in the immunotoxicity of cadmium, the membrane pathway for intracellular cadmium accumulation is not fully elucidated. To characterize membrane Cd(2+) transport of rat thymocytes, the change in intracellular Cd(2+) concentration under various conditions was examined by the use of Fluo-3, a fluorescent probe for monitoring the change in intracellular concentration of divalent metal cations. The membrane Cd(2+) transport was estimated by the augmentation of Fluo-3 fluorescence induced by bath application of CdCl(2).

A highly efficient carbon-carbon bond formation reaction via nucleophilic addition to N-alkylaldimines without acids or metallic species.

A nucleophilic addition reaction to N-methylaldimines without acid or metal species is described. A novel reagent, dicyanomethyl acetate, is used as a nucleophile to give alpha-(N-methyl-N-acetyl)amino acid methyl esters in excellent yield.

Cytometric analysis of adverse action of diphenyl ditelluride on rat thymocytes: cell shrinkage as a cytotoxic parameter.

Despite the growing use of organotellurium compounds in the chemical and biomedical fields, there has been no great concern about their toxicity until now. To test the possibility that diphenyl ditelluride (DPDT) and tellurium chloride (TeCl2), organic and inorganic tellurium compounds, may exert adverse action on mammals, their effects on rat thymocytes were examined under in vitro conditions using a flow cytometer with fluorescent probes. Incubation of thymocytes with DPDT at 300 nM or more for 24 h significantly increased the populations of shrunken cells and of cells with hypodiploidal DNA.

A convenient procedure for bismuth-mediated Barbier-type allylation of aldehydes in water containing fluoride ions.

A new and convenient procedure for synthesis of homoallylic alcohols in generally good to excellent yields has been developed. The bismuth-mediated Barbier-type allylation of aldehydes (aromatic, aliphatic, alicyclic and heterocyclic) with allyl bromide has been carried out smoothly in water in the presence of fluoride ions.