Vitrimers are a subclass of covalent adaptable networks which introduce reshapeability and recyclability in thermoset materials while maintaining high degree chemical resistance dimensional stability. Vitrimer based on vinylogous urethane (VU) chemistry have drawn lot attention this area. Classically, these obtained by the polycondensation polymerization acetoacetate amine monomers. Unfortunate...

Rates of plasma acetoacetate and total ketone-body production and oxidation to CO2 were determined by an isotope tracer technique in eight obese subjects undergoing progressive starvation. After a brief fast and under conditions of mild ketonemia and minimal ketonuria, rates of acetoacetate and total ketone-body production and oxidation were directly related to the increasing plasma concentrati...

To non-anaesthetized rats starved for 3 days, [U-14C]acetone, NaH14CO3, L-[U-14C]lactate, [2-14C]acetate or D-[U-14C]- plus D-[3-3H]-glucose was injected intravenously. From the change in the plasma concentration of labelled acetone versus time after the injection, the metabolic clearance rate of acetone was calculated as 2.25 ml/min per kg body wt., and its rate of turnover as 0.74 mumol/min p...

The metabolism of millimolar concentrations of R- or S-1,3-butanediol has been studied in perfused livers from fed and starved rats. Protocols were designed to measure in the same experiment (i) uptake of the diol, (ii) the contribution of the diol to ketogenesis, (iii) the contribution of the diol to total fatty acid plus sterol synthesis, and (iv) conversion of S-1,3-butanediol into S-3-hydro...

We describe an automated kinetic assay for acetoacetate in blood. Acetoacetate is enzymatically reduced to D-beta-hydroxybutyrate and the reaction is monitored for 60 s with a reaction-rate analyzer. This technique allows low concentrations of acetoacetate to be measured with good precision and overcomes many of the problems associated with other automated techniques. Our studies on the stabili...

The title compound, C(15)H(21)NO(2), was obtained by the reaction of acetoacetate with 2,4,6-trimethyl-aniline using Mexican bentonitic clay as a catalyst. It crystallizes in the enamine form. The β-enamino ester residue is almost perpendicular to the aromatic ring [dihedral angle = 88.10 (6)°]. The mol-ecular conformation is stabilized by a strong intra-molecular N-H⋯O hydrogen bond. In additi...

Results for urinary glucose by the Boehringer Mannheim BM33071 test pad and a hexokinase-based method agree well. The new test, which involves the glucose oxidase/peroxidase reaction, measures as little as 260 mg of glucose per liter. Acetoacetate, beta-hydroxybutyrate, and human hemoglobin do not interfere.

The AtoS-AtoC two-component signal transduction system positively regulates the expression of the atoDAEB operon in Escherichia coli. Upon acetoacetate induction, AtoS sensor kinase autophosphorylates and subsequently phosphorylates, thereby activating, the response regulator AtoC. In a previous work we have shown that AtoC is phosphorylated at both aspartate 55 and histidine73. In this study, ...

A well supported mechanism for succinyl-CoA:3-ketoacid coenzyme A transferase (EC 2.8.3.5) involving an enzymeCoA intermediate requires the participation of an oxygen atom of the enzyme or of the CoA moiety. Measurements of loss of 180 from acetoacetate show that CoA oxygens do not participate. An oxygen-containing group on the enzyme is reversibly labeled from succinateJ*O in the presence of a...

* The trichloroacetic acid extracts were first acidified with sulfuric acid3 and kept overnight at 38” for decarboxylation of acetoacetate. The fluid was then neutralized with sodium hydroxide and phosphate, and the acetone distilled by the procedure of Folin.4 Acetone was determined calorimetrically by the method of Behre.6 Analogous results were obtained with the determination procedure of Le...