ABSTRACT
[figure: see text] 2-Amino C-glycerolipid 1b was synthesized by using the Ramberg-Bäcklund rearrangement as the key step. beta-C-Glycerolipid 1b exhibits in vitro antiproliferative effects strikingly similar to those of O-glycoside analogue 1a.
Subject(s)
Antineoplastic Agents/chemical synthesis , Cell Division/drug effects , Glucosamine , Glycolipids/chemical synthesis , Glycolipids/toxicity , Antineoplastic Agents/chemistry , Antineoplastic Agents/toxicity , Female , Glycolipids/chemistry , Humans , Male , Molecular Structure , Tumor Cells, CulturedABSTRACT
The C-acylation of Meldrum's acid by protected amino acids, using isopropenyl chloroformate (IPCF) as the condensing agent, is described. The process is used to synthesize gamma and delta-amino-beta-keto-esters.
Subject(s)
Esters/chemical synthesis , Acylation , Esters/chemistry , Magnetic Resonance Spectroscopy , Molecular Structure , Spectroscopy, Fourier Transform InfraredABSTRACT
[formula: see text] A novel methodology has been developed, employing the Ramberg-Bäcklund rearrangement and ionic hydrogenation to synthesize C-glycosides with high stereoselectivity at the anomeric center. The C-glycolipid 14b exhibits antiproliferative properties similar to those of O-glycoside analogue 14a.
Subject(s)
Antineoplastic Agents/chemical synthesis , Glycolipids/chemical synthesis , Drug Screening Assays, Antitumor , Humans , Molecular Conformation , Stereoisomerism , Tumor Cells, CulturedABSTRACT
[formula: see text] This letter describes the reduction to practice of a novel concept for functionalization of the anomeric carbon of carbohydrates with a nitrogen substituent. Thus, bisheterodienes with a thiono sulfur terminus and a sulfonylimine terminus are shown to undergo cycloaddition smoothly and stereoselectively to three different glycals.
Subject(s)
Glucosides/chemical synthesis , Nitrogen/chemistry , Glycosylation , Stereoisomerism , Sulfur/chemistryABSTRACT
Arylbis(arylthio)sulfonium salts have been used to activate glycals towards nucleophilic addition to form principally 2-deoxy-beta-glycosides. This method was applied to the synthesis of the 2-(methylphenylthio)-2'-phenylthio derivative (22) of methyl O-(4-O-benzyl-2,6-dideoxy-beta-D-arabino- hexopyranosyl)-(1-->3)-3,4-di-O-benzyl-2,6-dideoxy-2,6-beta-D-arabino- hexopyranoside, the C'D' ring analog of an aureolic acid disaccharide. The condensation of 1,5-anhydro-2,6-dideoxy-D-arabino-hex-1-enitol with methanol in the presence of the phenylbis(phenylthio)sulfonium salt resulted in formation of the first beta-glycoside linkage. The methyl 6-deoxyglucoside obtained was deprotected at HO-3 to give the 2-thiophenyl-substituted 2,6-dideoxy-beta-glucoside. This was coupled with 1,5-anhydro-3,4-di-O-benzyl-2-deoxy-D-arabino-hex-1-enitol in the presence of 4-methylphenyl[bis(4-methylphenyl)thio]sulfonium salt to give the (1-->3)-linked disaccharide 22. Finally, desulfurization of 22 using WII Raney nickel generated the required 2,2'-dideoxydisaccharide.
