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.

Cytochrome c was reduced by ferrous EDTA over the pH range 0.7 to 5.5, but not by ferrous ions alone. A typical hemochromogen of the low spin type was observed between pH 2.2 and 5.5, but spectra of the high spin type were seen between pH 0.7 and 2.1. CO-Ferrocytochrome c was obtained over the pH range of 1.6 to 3.2 by this method. The spectrum was similar to that of alkaline CO-ferrocytochrome...

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 ...

Carbapenemases have great importance in the global epidemiological scenario since infections with carbapenemase-producing bacteria are associated with high mortality, especially in hospitalized patients in intensive care units. This study describes two microorganisms producers of the New Delhi Metallo-b-lactamase, Klebsiella pneumoniae and Citrobacter freundii, from two patients admitted to a p...

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 one-pot, multi-component synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ols) by tandem Knoevenagel-Michael reaction of phenylhydrazine, ethyl acetoacetate and aldehydes in the presence of silica-bonded N-propylpiperazine sulfamic acid (SBPPSA) as a recyclable solid acid catalyst was reported. SBPPSA showed much the same efficiency when used in consecutive reaction runs.

Ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), and other synthetic polycarboxylic acids have been shown to possess substantial capacity as washing agents of heavy metal-polluted soils, but they are environmentally problematic. Therefore, a sample of natural soluble humic substances (HS) was tested as a possible substitute. The efficiency of HS to extract cadmium (Cd), copp...

The 3-deoxy-d-arabinoheptulosonic acid-7-phosphate synthetase which is subject to regulation by tryptophan has been partially purified from a strain of Escherichia coli K-12, in which this is the only functional form of this enzyme activity, and from a similar strain possessing a feedback-resistant form of the enzyme. Maximal observed inhibition by tryptophan of the feedback-sensitive enzyme wa...

The one-pot efficient synthesis of novel functionalized organoselenium compound by bis-alkoxyselenenylation alkenes with selenium dibromide and alcohols was developed. reaction the cyclopentene or cyclohexene in system alcohol/sodium bicarbonate/methylene chloride at room temperature afforded bis(2-alkoxycycloalkyl) selenides 90–99% yields. regioselective method for bis-alkoxylation terminal de...