746639-75-8

Upstream product

• 148432-25-1 (S,S)-(+)-1-[3-Hydroxy-1-(2,6-di-tert-butyl-4-methoxy-1-phenoxycarbonyl)-3-phenyl-1-propylideneamino]-2-(1-ethyl-1-methoxypropyl)pyrrolidine 
• 204511-99-9 (S)-3-[(E)-(S)-2-(1-Ethyl-1-methoxy-propyl)-pyrrolidin-1-ylimino]-5-phenyl-dihydro-furan-2-one 
• 67-56-1 methanol 

Relevant academic research and scientific papers

Highly stereoselective oxy-Michael additions to β,γ-unsaturated α-Keto Esters: Rapid enantioselective synthesis of 3-hydroxybutenolides

The highly diastereoselective oxy-Michael addition of the "naked" anion of (6S)-methyl δ-lactol to γ-substituted β,γ- unsaturated α-keto esters leading to the direct formation of THP*-protected γ-hydroxy α-keto ester derivatives is described. Subsequent a

Enantioselective synthesis of protected isotetronic acids

Isotetronic acids are subunits of a number of natural products. They are of interest in agricultural and pharmaceutical research and are important synthetic intermediates. This paper describes the first highly diastereo- and enantioselective synthesis of isotetronic acids in 4 to 5 steps (de, ee > 98%). Key steps in the reaction sequence are the diastereoselective aldol reaction of the 2-oxoesters 5 as their SAEP hydrazones (S)-6 with aldehydes, followed by base-promoted lactonization to the hydrazonolactones 8. Subsequent oxidative cleavage of the hydrazone moiety afforded the enantiomerically pure O-protected isotetronic acids (R)-/(S)-9.