204511-92-2

Upstream product

• 609798-33-6 2,6-di-tert-butyl-4-methoxyphenyl ethyl oxalate 
• 145656-72-0 2,6-di-tert-butyl-4-methoxyphenyl pyruvate 
• 489-01-0 2,6-Di-t-butyl-4-methoxyphenol 
• 78008-36-3 (R)-2,3-cyclohexylideneglyceraldehyde 
• 148432-21-7 (S)-(+)-1-[1-(2,6-Di-tert-butyl-4-methoxy-1-phenoxycarbonyl)-1-ethylideneamino]-2-(1-methoxy-1-ethylpropyl)pyrrolidine 

Relevant academic research and scientific papers

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.