99457-63-3

Upstream product

• 1576-35-8 toluene-4-sulfonic acid hydrazide 
• 94744-89-5 (2R,3R,3aR,6S,7S,7aR)-6-carboxy-7-(hydroxymethyl)-2,3-(isopropylidenedioxy)-6-methyl-5-oxooctahydrobenzo<4,3-b>furan 6,7-lactone 

Downstream Products

• 99457-79-1 3-[(3aR,4aR,5R,6S,8aR,8bR)-2,2,6-Trimethyl-5-(toluene-4-sulfonyloxymethyl)-octahydro-benzo[4,5]furo[2,3-d][1,3]dioxol-6-yl]-propionic acid ethyl ester 
• 99457-81-5 (2R,3R,3aR,6S,7S,7aS)-6β-<(ethoxycarbonyl)ethyl>-2,3-(isopropylidenedioxy)-6-methyl-7-<(phenylsulfonyl)ethyl>octahydrobenzo<3,4-b>furan 

Relevant academic research and scientific papers

Controlled Access to Furanose Precursors Related to Sesquiterpene Lactones. 2

Compound 1a, whose synthesis is described in the accompanying manuscript, represents the B-C ring system of the eudesmane sesquiterpene lactones.The A ring is represented by the γ-lactone of 1a, and steps for its elaboration include ring expansion and epimerization at C-5.In order to achieve these objectives the lactone was reduced to lactol 3 which showed very little tendency to react as the hydroxy-aldehyde counterpart.However 3 yields N,N-dimethylhydrazone 6a which provides access to the C-5 primary alcohol.This center is eventually epimerized by oxidation to an aldehyde, 8, which is converted to the enol acetate 12 and hydrogenated.The A ring is formed by the intramolecular reaction of a β-keto sulfone and a primary iodide.