The inhibition of phospholipase A2 by an amide substrate analogue, 1-hexadecylthio-2-hexadecanoyl-amino-1,2-dideoxy-sn-glycero-3-phos phocholine, and a phosphonate transition-state analogue, 1-hexadecylthio-1-deoxy-2-hexadecylphosphono-sn-glycero-3-ph osphocholine, is dramatically influenced by pH. However, these two inhibitors show opposite pH dependencies. The amide analogue acts more potentl...

Phosphite is a less oxidized form of phosphorus than phosphate. Phosphite is considered to be taken up by the plant through phosphate transporters. It can mimic phosphate to some extent, but it is not metabolized into organophosphates. Phosphite could therefore interfere with phosphorus signalling networks. Typical physiological and transcriptional responses to low phosphate availability were i...

Introduction Lipases are lipolytic enzymes originating from a wide variety of sources, such as plants, microorganisms and higher animals. The most distinctive property of lipases is their rapid hydrolysis of ester bonds at an oil-water interface, whereas activity on monomeric substrates is generally low [l]. The first structures of lipases [2,3] already gave insight into their general architect...

a most effective and less energy demanding method of producing fatty esters, diol esters, by esterifying fatty acids, with neopentyl and ethylenglycol alcohols in the presence of an acidic ion exchange resin catalyst(polyestyrendivinylbenzensulfated) was investigated at elevated temperature. in this process an azeotroping agent, toluene, was used to facilitate continuous removal of water by dis...

The synthesis of twenty five esters of testosterone (17β -hydroxyandrost- 4-en-3-one) is described. All esters are derivatives of cycloalkycarboxylic acids. Some of the esters possess α- , β -and/or & - substitution in the ester side-chain. The work was undertaken in order to evaluate long-acting male antifertility effect of such esters. Most of the compounds, especially compound No.1, wer...

Stereochemical investigations have shown that the conversion of 2-hydroxyethylphosphonate to hydroxymethylphosphonate by the enzyme HEPD involves removal of the pro-S hydrogen at C2 and, surprisingly, the loss of stereochemical information at C1. As a result, the mechanisms previously proposed for HEPD must be re-evaluated.

Supramolecular bidentate phosphite ligands are presented as a new class of ligands for rhodium catalysed asymmetric hydrogenation.