Malonic acid silylatesreadily to yield the expected bis-trimethylsilyl (TMS) ester; this ester reacts further in the silylating mixture to yield a tris-TMS derivative, apparently through enolization of one of the ester groups. Methylmalonic and hydroxymalonic acids behave similarly. The methyl and ethyl esters of malonic acid also silylate once with some facility. Mass spectra of these derivati...

Cholesterol exists within the hepatocyte as free cholesterol and cholesteryl ester. The proportion of intrahepatic cholesterol in the free or ester forms is governed in part by the rate of cholesteryl ester formation by acyl-coenzyme A:cholesterol acyltransferase (ACAT) and cholesteryl ester hydrolysis by neutral cholesterol ester (CE) hydrolase. In other cell types both ACAT and CE hydrolase a...

In the crystal structure of the title compound, C(4)H(10)NO(2) (+)·Cl(-) (systematic name: 3-eth-oxy-3-oxopropan-1-aminium chlor-ide), there are strong inter-molecular N-H⋯Cl, C-H⋯Cl and C-H⋯O hydrogen-bonding inter-actions between the free chloride anion and the organic cation, resulting in a two-dimensional supra-molecular network in the ab plane.

Most organophosphorus esters are direct inhibitors or are rapidly converted to inhibitors of acetylcholinesterase (AChE, EC 3.1.1.7) (1-3). Some of these compounds produce a more persistent effect: delayed neurotoxicity. In humans, organophosphorus ester-induced delayed neurotoxicity (OPIDN) results in a flaccid paresis which develops distally in the legs and spreads to the hands and thighs. In...

Neutral Cholesterol Ester Hydrolases in Macrophages: Still a Matter of Debate To the Editor: In a recent study, Igarashi et al1 reported knockdown experiments using adenoviral short hairpin RNA constructs targeting human neutral cholesterol ester hydrolase-1 (NCEH1, originally named KIAA1363) and the potential cholesterol ester hydrolase CES1. The authors concluded that “NCEH1 is the only enzym...

Laboratory studies were conducted using C-aminocyclopyrachlor (DPX-MAT28) and its C-methyl ester formulation (DPX-KJM44) to (1) determine the adjuvants’ effects on absorption, (2) compare the absorption and translocation of aminocyclopyrachlor free acid with the methyl ester, and (3) determine the rate at which aminocyclopyrachlor-methyl ester is metabolized to the free acid in Canada thistle. ...

A direct α-functionalization of simple aldehydes under N-Heterocyclic Carbene (NHC) catalysis and direct generation of ester enolate equivalents from nonfunctionalized aldehydes are disclosed. The catalysis involves selective enolate generation from an oxidatively generated NHC-bounded ester intermediate as a key step. The ester enolate intermediates undergo stereoselective reactions with enone...

Since that time, new data have become available, and these have been incorporated into the monograph and taken into consideration in the present evaluation. Chem. Abstr. Name: 1,2-Benzenedicarboxylic acid, bis(2-ethylhexyl) ester IUPAC Systematic Names: Bis(2-ethylhexyl) phthalate; phthalic acid, bis(2-ethyl-hexyl) ester Synonyms: Bis(2-ethylhexyl) 1,2-benzenedicarboxylate; bis(2-ethylhexyl) or...

N-Benzyloxycarbonyl derivatives of isoglutamine and isoasparagine were coupled with arginine methyl ester through the action of dicyclohexylcarbodiimide. The resulting benzyloxycarbonyl derivatives of isoglutaminylarginine methyl ester and isoasparaginylarginine methyl ester were treated with trypsin for removal of the ester groups and then with porcine pancreatic carboxypeptidase B for liberat...

The extraction of yacon [Smallanthus sonchifolius (Poepp. and Endl.) H. Robinson; Asteraceae] leaves and chromatographic separation yielded two new antibacterial melampolide-type sesquiterpene lactones, 8beta-tigloyloxymelampolid-14-oic acid methyl ester and 8beta-methacryloyloxymelampolid-14-oic acid methyl ester, as well as the four known melampolides, sonchifolin, uvedalin, enhydrin and fluc...