slowly to -10°C and the reaction solution was poured under vigorous stirring into a mixture containing 600 mL of saturated sodium chloride solution and 300 mL of diethyl ether. In order to remove the THF, the organic phase was washed several times with water and then dried with sodium sulfate. After removal of the ether, the product mixture was separated on 400 g of neutral alumina (activity 111) at -20°C with pentanelether (100. I) as eluent. It was thereby possible to elute four fractions: diazo compound 3141, tetrazine 4, acyl diimide 5 , and a small amount (4%) of the dihydro derivative of 4.
As a precursor for the chemical synthesis of sialylated oligosaccharides, the trisaccharide glycoside Neu5Ac alpha (2-8)Gal beta (1-4)GlcNAc beta (1-O)-pent-4-ene was synthesized starting from GlcNAc beta (1-O)-pent-4-ene, UDP-glucose and N-acetylneuraminic acid in a one pot reaction employing galactosyltransferase and alpha (2-6)sialyltransferase in a complete cofactor regeneration system.
tenflache eine zusatzliche diagonale Bindung (Fe2-Fe3) aufweist (Abb. 1).2 wird sowohl photochemisch als auch thermisch unter Geriistumlagerung zu 3 decarbonyliert. In 3 fungiert die RP-Gruppe wieder als k3-Ligand. Die P-C-Bindung zum Alkinfragment wird gelost, und die Ph2C2-Einheit uberbriickt eine Kante des Eisendreiecks. Die durch die Decarbonylierung freigewordene Koordinationsstelle wird durch n-Wechselwirkung mit dem briickenstandigen Alkin abgesattigt (Abb. 2). ganzen erinnert das beobachtete Reaktionsmuster sehr stark an die Chemie von Carboranen1I2l. Anorganisch-chemisches lnstitut der UniversitPt CorrensstraBe 36, 0.4400 Monster Angew. Chem. 98 (1986) Nr. 12 Cd VCH Verlagsgesellschaff mbH. 0-6940 Weinheim. 1986
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.