N-Allyloxycarbonyl derivatives of D-glucosamine as promotors of 1,2-trans-glucosylation in Koenigs–Knorr reactions and in Lewis acid catalyzed condensations

Abstract

. 65, 1343 (1987).The use of suitably blocked D-glucosamine derivatives possessing the N-allyloxycarbonyl protective group of the amino function represents potential new routes to 1,2-trans-glucosylations. Both 3,4,6-tri-O-acetyl-2-N-allyloxycarbonyl-2-amino-2-deoxy-a-D-glucopyranosyl bromide (2) and 1,3,4,6-tetra-O-acetyl-2-N-allyloxycarbonyl-2-amino-2-de0xy-~-~-glucopyranose (3) could be used in Koenigs-Knorr reactions or Lewis acid catalyzed condensations, respectively. Glucosides of simple alcohols and disaccharides were synthesized in good to excellent yields. The N-allyloxycarbonyl protective group was, moreover, easy to remove with Pd(0) complexes, thus affording, after acetylation, the corresponding N-acetyl-P-D-glucosamine glucosides under very smooth conditions. PAUL BOULLANGER, JOSEPH BANOUB et GBRARD DESCOTES. Can. J. Chem. 65, 1343Chem. 65, (1987. L'utilisation de derives de la D-gl~co~amine protCgCs sur la fonction amine par un groupement N-allyloxycarbonyle constitue une nouvelle voie d'accbs potentielle aux glucosides 1,2-trans. Le bromure de tri-0-acCtyl-3,4,6 N-allyloxycarbonyl-2-amino-2 dCsoxy-2 a-D-glucopyrannosyle (2) et le tttra-0-acCtyl-1,3,4,6 N-allyloxycarbonyl-2 amino-2 dCsoxy-2 6-D-glucopyrannose (3) peuvent etre utilists respectivement dans les reactions de type Koenigs-Knorr ou dans les condensations catalysCes par les acides de Lewis. Les glucosides d'alcools simples et les disaccharides ont CtC prCparCs avec des rendements de bons excellents. Le groupe protecteur N-allyloxycarbonyle est, de plus, facile a cliver avec les complexes du Pd(0) et conduit, aprks acktylation, aux glucosides de la N-acCtyl P-D-gl~co~amine dans des conditions trbs douces.

Kinetics Study of Bungarus fasciatus Venom Acetylcholinesterase Immobilised on a Langmuir–Blodgett Proteo‐Glycolipidic Bilayer

“…Elemental analysis calcd (%) for C 37 H 76 O 6 (M W 617.00): C 72.03, H 12.42; found C 71.87, H 12.19. This derivative was condensed with 1,3,4,6-tetra-O-acetyl-2-allyloxycarbonylamino-2-deoxy-b-d-glucopyranose [38] in CH 2 Cl 2 , in the presence of trimethylsilyl triflate, to afford the expected b-glucoside in 72 % yield. This was finally deprotected in aqueous NaOH (4 n) and re-N-acetylated to afford 10-tetradecyloxymethyl-3,6,9,12-tetraoxahexacosyl 2-acetamido-2-deoxy-b-d-glucopyranoside in 78 % yield.…”

Recent trends in the synthesis of O-glycosides of 2-amino-2-deoxysugars

“…255 In contrast, glycosidation of b-acetate 107 with glycosyl acceptor 29 in the presence of trimethylsilyl triflate (TMSOTf) provided disaccharide 109 in 82% yield with no formation of side product 110. 254 In an attempt to improve the reactivity as well as to expand the scope of applications, a variety of leaving groups with a 2-N-allyloxycarbonyl moiety have been developed over the years, for example, trichloroacetimidates 256 and thioglycosides. 257 The derivatives of 2-Nallyloxycarbonyl sugars have been applied to the synthesis of peptidoglycan partial structures, 258 glycopeptide assemblies, 256,259 1,6-anhydro derivatives, 260 neoglycolipid analogues, 261 N-acetylneuraminic acid derivatives, 257 and surfactants.…”

Studies Directed to the Synthesis of Oligochitosans – Preparation of Building Blocks and Their Evaluation in Glycosylation Studies

“…After recrystallization in ethyl acetate compound 7 was isolated as colorless crystals (1.33 g, 79 %). 1 [29] (1.98 g, 4.60 mmol) in CH 2 Cl 2 (20 mL) was treated with p-thiocresol (803 mg, 6.47 mmol) and boron trifluoride-diethyl ether (0.70 mL, 5.53 mmol) as described for compound 6. The product was purified by column chromatography (EtOAc/pentane, 2:3) to give 8 (1.60 g, 70 %) as a white solid.…”