99260-77-2

Upstream product

• 67-56-1 methanol 
• 69127-07-7 (2R,3S,4R)-2,3-trans-3,4-cis-3-acetoxy-4-<(2R,3S)-2,3-trans-3-acetoxy-3,3',4',5,7-pentamethoxyflavan-8-yl>-3',4',7-trimethoxyflavan 

Downstream Products

• 69119-50-2 8-bromo-3-O-acetyl-3',4',5,7-tetra-O-methyl-(+)-catechin 
• 99260-78-3 Acetic acid (2R,3R)-6-bromo-2-(3,4-dimethoxy-phenyl)-4,4,7-trimethoxy-chroman-3-yl ester 

Relevant academic research and scientific papers

Regio- and stereoselective oxidation of flavan-3-ol-, 4-arylflavan-3-ol-, and biflavanoid derivatives with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)

The phenolic methyl esthers of flavan-3-ols, 4β-arylflavan-3-ols, and (-)-fisetinidol-(4β,8)-(+)-catechin biflavanoids are susceptible to regio- and stereoselective methoxylation at C-4 in moderate yields with DDQ in CHCl3-MeOH solution. The observed asymmetric induction with exclusive formation of 2,4-trans products is compatible with the intermediacy of a diastereogenic donor-acceptor interaction, DDQ acting as the acceptor and oxidant. The 4-funtionalized analogues are of both synthetic and degradative significance in condensed tannin chemistry.