154815-06-2

Upstream product

• 154321-89-8 (4aS,5R)-5-(benzyloxy)-2,4a,5,6,7,8-hexahydropyrido<1,2-b><1,2>oxazin-8-one 
• 154814-99-0 (E)-(R)-3-(benzyloxy)-1-<(p-tolylsulfonyl)oxy>-4,6-heptadiene 
• 154815-00-6 (E)-(R)-4-(benzyloxy)-5,7-octadienonitrile 
• 154815-02-8 methyl (E)-(R)-4-(benzyloxy)-5,7-octadienoate 
• 154815-14-2 (E)-(3R)-3-(benzyloxy)-4,6-heptadienol 
• 154815-01-7 (E)-(R)-4-(benzyloxy)-5,7-octadienic acid 
• 154321-85-4 (E)-(R)-4-(benzyloxy)-N-hydroxy-5,7-octadienamide 
• 102794-92-3 (2R,4R)-4-formyl-2-phenyl-1,3-dioxane 
• 18162-48-6 tert-butyldimethylsilyl chloride 
• 154815-05-1 (2S,3R)-3-(benzyloxy)-2-<(Z)-3-hydroxy-1-propenyl>piperidin-6-one 

Relevant academic research and scientific papers

New Chiral Route to (-)-Swainsonine via an Aqueous Acylnitroso Cycloaddition Approach

A new noncarbohydrate-based enantioselective approach to (-)-swainsonine (1) is described, in which the aqueous intramolecular Diels-Alder reaction of a chiral acylnitroso diene has been employed as a key reaction.The intramolecular cycloaddition of the chiral hydroxamic acid 9, available from D-malic acid in 10 steps, with Pr4NIO4 was conducted under the conventional nonaqueous conditions using CHCl3 as a solvent, whereupon intermediacy acylnitroso compound 10 cyclized spontaneously to give the trans- and cis-1,2-oxazinolactams 11 and 12 with a low diastereoselection af 1.3:1 in 76percent combined yield.When the corresponding reaction was performed in water, it led to significant enhancements of trans selectivity of 4.1:1 as well as combined yield (89percent).The trans adduct 11 was subjected to reductive N-O bond cleavage followed by diastereoselective hydroxylation with OsO4 to provide the 1,2-glycol 21, which was then converted to the amino alcohol 25.Intramolecular cyclodehydration of 25 with CBr4/PPh3/Et3N and subsequent deprotection furnished (-)-swainsonine (1).