L-phenyta}anine methy] ester (Phe-OMe) as substrates was dene mainly in a water-organic one phase solvent system. The organic so]yent content used was less than the saturatien concentration in buffer. With organic solvents with high logP ya]ues, the enzymatic actiyity increased as the organic solyent content increased; but further increases in the organic solvent content decreased the enzymatic...

Two kinds of novel chiral molecular tweezers containing imidazoliums were synthesized from L-alanine, L-phenylalanine, and L-glutamic acid. They are constructed by the chiral imidazolium pincers and two different spacers which are 1,3-bis (bromomethyl)benzene and 2,6-bis(bromomethyl)pyridine, respectively. The enantioselective recognition of L- and D-amino acid derivatives by these molecular tw...

Addition of the synthetic chemotactic factor, formyl-methionyl-leucyl-phenylala-nine (F-Met-Leu-Phe) to medium containing magnesium, sodium, and potassium results in a doubling of the "Na+, K+"-ATPase activity of the plasma membrane fraction from polymophonuclear leukocytes (PMN). This activation is sensitive to ouabain inhibition and is dose dependent, maximal activity occuring at 10(-9)MF-Met...

Aspartame is a dipeptide (L-aspartyl-L-phenylalanyl methyl ester) with a sweetening potential of 180 to 200 times that of sucrose. Questions have been raised about the potential toxic effects of its constitu ent amino acids when the compound is ingested in large amounts by lactating women. Plasma, erythrocyte and milk levels of free amino acids were measured in six normal female subjects with e...

Novel synthetic approaches to chiral ethylene-bridged ansa-titanocenes possessing stereogenic centers on the bridging carbon chain are described. A key step in the preparation of these compounds is the double-Skatteberl rearrangement of bis(vinyldibromocyc1opropane) intermediates derived from 1,4-disulfones. The influence of tether substitution on the diastereoselection in ansa-titanocene forma...

Considering the largely chiral nature of biological systems, there is interest in drug delivery systems. Here, we investigate for first time polymer micelles based on poly(2-oxazoline) (POx) ABA-type triblock copolymers with and racemic hydrophobic blocks formulation achiral drugs. Specifically, poly(2-ethyl-4-ethyl-2-oxazoline) (pEtEtOx) poly(2-propyl-4-methyl-2-oxazoline) (pPrMeOx) were used ...

Oil-induced mononuclear phagocytes (MN) were quantitatively assayed for various hydrolases as unfractionated suspensions of frozen and thawed cells. They apparently contain two proteases. The first, measured with urea- or acid-denatured hemoglobin, was similar to purified Proteinase I of lung with respect to pH optimum (pH 4), stability, hydrolytic and polymerizing activities, and reactions to ...

      The fruit of Melia azedarach L. (Meliaceae) was extracted with hexane, and its fatty acids methyl ester was analyzed using GC/MS. Thirteen components representing 85.1% of the total extract were identified. The major components identified were methyl palmitate (18.8%), methyl linolenate (16.1%) and methyl linoleate (9.8%). The fruits’ extract had a LC50 of 5.5 ppm agai...