3888-39-9

Basic information

• Product Name: (2R,3R)-2,3-cis-3-acetoxy-8-<(2R,3R,4R)-2,3-cis-3,4-trans-3-acetoxy-3',4',5,7-tetramethoxyflavan-4-yl>-3',4',5,7-tetramethoxyflavan
• CAS NO: 3888-39-9
• Molecular Weight: 774.819
• Mol File: 3888-39-9.mol

Chemical Properties

• CAS DataBase Reference: (2R,3R)-2,3-cis-3-acetoxy-8-<(2R,3R,4R)-2,3-cis-3,4-trans-3-acetoxy-3',4',5,7-tetramethoxyflavan-4-yl>-3',4',5,7-tetramethoxyflavan(CAS DataBase Reference)
• NIST Chemistry Reference: (2R,3R)-2,3-cis-3-acetoxy-8-<(2R,3R,4R)-2,3-cis-3,4-trans-3-acetoxy-3',4',5,7-tetramethoxyflavan-4-yl>-3',4',5,7-tetramethoxyflavan(3888-39-9)
• EPA Substance Registry System: (2R,3R)-2,3-cis-3-acetoxy-8-<(2R,3R,4R)-2,3-cis-3,4-trans-3-acetoxy-3',4',5,7-tetramethoxyflavan-4-yl>-3',4',5,7-tetramethoxyflavan(3888-39-9)

Safety Data

• Hazardous Substances Data: 3888-39-9(Hazardous Substances Data)

Upstream product

• 186581-53-3 diazomethane 
• 25095-07-2 4β-methoxy-tetra-O-methyl-3-O-acetyl-(-)-epicatechin 
• 154-23-4 catechin 
• 87303-91-1 (2R,3S,4S)-2-(3,4-dimethoxyphenyl)-4,5,7-trimethoxychroman-3-ol 
• 51196-02-2 5,7,3',4'-tetra-O-methylepicatechin 
• 490-46-0 (2R,3R)-2-(3,4-dihydroxyphenyl)-3,4-dihydro-1[2H]-benzopyran-3,5,7-triol 
• 22970-70-3 (2R,3R,4S)-2,3-cis-3,4-trans-3',4',5,7-tetramethoxyflavan-3,4-diol 
• 37064-32-7 5,7,3',4'-tetra-O-methylepicatechin-4β,8-(5,7,3',4'-tetra-O-methylepicatechin) 
• 108-24-7 acetic anhydride 
• 37126-92-4 5,7,3',4',5'',7'',3''',4'''-octa-O-methylprocyanidin B-3 

Relevant articles and documents

Oligomeric flavanoids. Part 19. Reductive cleavage of the interflavanyl bond in proanthocyanidins

The interflavanyl bond in profisetinidins 1, 4 and 6, and methyl ethers 3, 5, 28 and 29 procyanidins 24 and 26, and their methyl ethers 25 and 27 is readily subject to cleavage with sodium cyanoboranuide in trifluoroacetic acid at 0 deg C.This method will contribute significantly to the structure elucidation of the 5-deoxy (A-ring) proanthocyanidins from important commercial sources.Boltzmann-averaged heterocyclic ring coupling constants as determined by a conformational global search routine (GMMX) and NOE difference spectroscopy were used to assign unequivocally the diastereotopic methylene protons in the 1H NMR spectra of flavan-3-ols, a prerequisite for corroboration of the cleavage mechanism.

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.

SYNTHESIS AND CHARACTERIZATION OF PROCYANIDIN DIMERS AS THEIR PERACETATES AND OCTAMETHYL ETHER DIACETATES

Key Word Index - Biomimetic synthesis; procyanidins B1-B8; 3,4-cis-biflavanoid; all--bi--(+)-catechin; 1H NMR parameters. Condensation of (2R,3S,4R or S)-leucocyanidin or the 5,7,3',4'-tetramethyl ether of (2R,3R,4S)-leucocyanidin with flavan-3-ols yielded dimeric flavanoids which were converted to their octamethyl ether diacetates, or the deca-acetates for the 2,3-trans-procyanidin series.Comparison is made of the 1H NMR spectra of the deca-acetate and octamethyl ether diacetate derivatives which lead to useful diagnostic shift parameters characteristic of their structures.Condensation afforded a novel biflavanoid with a 3,4-cis-configuration and a triflavanoid of 'mixed' stereochemistry.

Synthesis of Condensed Tannins. Part 12. Direct Access to - and -all-2,3-cis-Procyanidin Derivatives from (-)-Epicatechin: Assessment of Bonding Positions in Oligomeric Analogues from Crataegus oxyacantha L.

Synthesis of methyl ester acetates of - and -all-2,3-cis-procyanidin biflavanoids is effected by oxidative functionalization of (-)-epicatechin tetramethyl ester with lead tetra-acetate, and condensation of the resultant 2,3-cis-flavan-3,4-diol

Synthesis of Condensed Tannins. Part 9. The Condensation Sequence of Leucocyanidin with (+)-Catechin and with the Resultant Procyanidins

Molar equivalents of synthetic (2R,3S,4R of S)-leucocyanidin and (+)-catechin condense with exceptional rapidity at pH 5 under ambient conditions to give the all-trans-- and -bi- (procyanidins B3, B6) the all-trans-- and -tri- (procyanidin C2, and novel isomer), and the presumed all-trans--linked tetraflavanoid analogue in the proportions 10:1:12:1:3.The facility and sequence of these condensations correlate with the observed absence of leucocyanidins (flavan-3,3',4,4',5,7-hexaols) and also the dominance of related condensed tannins in plant extracts.

Synthesis of Condensed Tannins. Part 4. A Direct Biomimetic Approach to - and -Biflavanoids

The generation of flavanyl-4-carbo-cations from flavan-3,4-diols and their condensation with nucleophilic flavan-3-ols to form - and -biflavanoids at ambient temperatures and mildly acidic aqueous conditions apparently simulates the initial step in condensed tannin formation in a number of natural sources.The stereospecificity (or stereoselectivity) of the reaction is conditioned mainly by the 2,3-cis or 2,3-trans stereochemistry of the parent flavan-3,4-diol, but also by the nuclephilicity of the flavan-3-ol, and its regiospecific (or regioselective) course by steric factors arising from variation in substitution of the receptive A-ring of the flavan-3-ol.