157220-06-9

Upstream product

• 259258-22-5 (3R,4R,5R)-5-[(1S,2S)-1-Benzyloxy-2-((2R,3R)-3-methoxymethoxymethyl-oxiranyl)-propyl]-4-hydroxy-3-methyl-dihydro-furan-2-one 
• 100-39-0 benzyl bromide 
• 1469-70-1 allyl ethyl carbonate 
• 259258-16-7 (3S,3aR,5S,6S,7S,7aS)-7-Benzyloxy-5-methoxy-3,6-dimethyl-hexahydro-furo[3,2-b]pyran-2-one 
• 68907-47-1 methyl 4,6-O-benzylidene-2-deoxy-2-C-methyl-α-D-altro-pyranoside 
• 109958-35-2 (2R,4aR,6S,7S,8S,8aS)-8-Benzyloxy-6-methoxy-7-methyl-2-phenyl-hexahydro-pyrano[3,2-d][1,3]dioxine 
• 259258-15-6 (2S,3S,4S,5S,6S)-4-Benzyloxy-2-iodomethyl-6-methoxy-5-methyl-tetrahydro-pyran-3-ol 
• 157219-91-5 ((2R,3R,4S,5S,6S)-4-Benzyloxy-3-hydroxy-6-methoxy-5-methyl-tetrahydro-pyran-2-yl)-acetaldehyde 
• 157220-01-4 (3R,4R,5S)-5-[(1S,2S)-1-Benzyloxy-2-((2R,3R)-3-methoxymethoxymethyl-oxiranyl)-propyl]-4-(tert-butyl-dimethyl-silanyloxy)-3-methyl-dihydro-furan-2-one 
• 157219-98-2 (E)-(4R,5S)-5-Benzyloxy-5-[(2S,3R,4R)-3-(tert-butyl-dimethyl-silanyloxy)-4-methyl-5-oxo-tetrahydro-furan-2-yl]-4-methyl-pent-2-enoic acid ethyl ester 
• 157219-96-0 (3R,4R,5S)-5-((1S,2S)-1-Benzyloxy-2-[1,3]dithian-2-yl-propyl)-4-(tert-butyl-dimethyl-silanyloxy)-3-methyl-dihydro-furan-2-one 
• 157220-00-3 (3R,4R,5S)-5-[(1S,2S)-1-Benzyloxy-2-((2R,3R)-3-hydroxymethyl-oxiranyl)-propyl]-4-(tert-butyl-dimethyl-silanyloxy)-3-methyl-dihydro-furan-2-one 
• 157219-89-1 Toluene-4-sulfonic acid (2R,3S,4S,5S,6S)-4-benzyloxy-3-hydroxy-6-methoxy-5-methyl-tetrahydro-pyran-2-ylmethyl ester 
• 157219-99-3 (3R,4R,5S)-5-((E)-(1S,2R)-1-Benzyloxy-5-hydroxy-2-methyl-pent-3-enyl)-4-(tert-butyl-dimethyl-silanyloxy)-3-methyl-dihydro-furan-2-one 

Relevant academic research and scientific papers

Stereocontrolled synthesis of the JKLM ring fragment of ciguatoxin

A highly stereocontrolled synthesis of the JKLM ring fragment of ciguatoxin has been achieved. The present synthesis starts with methyl 4,6-O- benzylidene-2-deoxy-2-C-methyl-α-D-altropyranoside, whose configurations and substituents at C2-C5 correspond to those at C46-C49 of ciguatoxin, and involves as the key step base-induced 7-endo selective cyclization of a hydroxy epoxide for the efficient construction of the fully substituted oxepane ring K. Construction of the spiroether ring M was achieved by introduction of an allyl group to the ring L lactone followed by asymmetric dihydroxylation to install the C54 stereogenic center and acid-induced spiroketalization to furnish the protected KLM ring system. Finally, ring J was constructed by the method of Nicolaou to complete the synthesis of the JKLM ring fragment. The synthesis of a carboxylic acid derivative and its conjugation to carrier proteins to give an artificial antigen for development of an immunoassay system for the parent toxin molecule are also reported.