Dihydromyricetin (DMY) is a health-beneficial flavanonol in the family of flavonoids, extracted from Ampelopsis grossedentata (Hand.-Mazz.) W. Wang. When investigating stability DMY Dulbecco's modified Eagle's medium (DMEM) solution at 37°C by LC-MS/MS, four nitrogenous derivatives were found except for previously known dimers, oxidized products, and ring-cleavage products DMY. Compound 1 (N-DM...

A chemoenzymatic approach for the synthesis of ?-N-heterocyclic ethyl- and phenylacetamides, levetiracetam analogs, is described. Eight nitrile substrates were prepared through N-alkylation heterocycles (2-pyrrolidinone, 2-piperidinone, 2-oxopiperazine 1-methylpiperazine) directly from hydroxyl group ethyl phenyl ?-hydroxynitriles with yield 35?71% after 12 h. Twenty hydratases (NHases) screene...

This paper evaluates the concentrations of water- and fat-soluble precursors of meat flavour, with the aim of characterising the effect of species on the volatile profile of grilled goat and lamb meat. Compared to goat, lamb meat had higher levels of saturated fatty acids--SFA, monounsaturated fatty acids--MUFA and polyunsaturated fatty acids--PUFA and similar levels of sugars and free amino ac...

Glycopeptides were isolated from a proteolytic digest of human transferrin. After mild acid hydrolysis the desialylated glycopeptides were labelled by the galactose oxidase/NaB(3)H(4) procedure and then fractionated by Sephadex-gel filtration or by anion-exchange chromatography. Either technique allowed separation of the two heterosaccharide chains (designated glycan I and glycan II) previously...

NH3 is an essential molecule as a nitrogen source for prebiotic amino acid syntheses such as the Strecker reaction. Previous shock experiments demonstrated that meteorite impacts on ancient oceans would have provided a considerable amount of NH3 from atmospheric N2 and oceanic H2O through reduction by meteoritic iron. However, specific production mechanisms remain unclear, and impact velocities...

We describe an enantioselective synthetic route to the antiproliferative alkaloid stephacidin B (1) proceeding in 18 steps and 4.0% yield from 4,4-(ethylenedioxy)-2,2-dimethylcyclohexanone (3). Key features of the synthetic sequence include the use of the Corey-Bakshi-Shibata (CBS) reduction to introduce asymmetry early in the synthetic route, use of the novel electrophile N-(tert-butoxycarbony...