20046-13-3Relevant academic research and scientific papers
Structure and synthesis of butiniflavan-epicatechin and - epigallocatechin probutinidins
Coetzee, Johan,Mciteka, Lulama,Malan, Elfranco,Ferreira, Daneel
, p. 737 - 743 (1999)
The rare series of dimeric proanthocyanidins with flavan chain extender units is extended by characterization of butiniflavan(4α → 8)- and (4β → 8)-epicatechins and butiniflavan-(4β → 8)-epigallocatechin from the bark of Cassia petersiana. The structure and absolute configuration of the dimers were confirmed by synthesis via reduction of the racemic flavanone, (±)- 7,3',4'-tri-O-methylbutin, to the diastereomeric flavan-4-ols and condensation with 5,7,3',4'-tetra-O-methylepicatechin and 5,7,3',4',5'-penta- O-methylepigallocatechin using titanium tetrachloride as Lewis acid.
STEREOSELECTIVITY AT BENZYLIC CARBON. FLAVANOIDS-V. SYNTHESIS OF TRANS-4-ACETAMIDOFLAVANS
Hirwe, A.,Marathe, K. G.,Mohorkar, S. S.,Ramdas, K.,Singh, C. B.
, p. 1539 - 1546 (2007/10/02)
Some reactions of 4-substituted flavans have been studied. 4-Chloro/bromo derivatives react under neutral conditions with phthalimide and acetonitrile leading to displacement of axial halogen by nitrogen with inversion.In contrast, irrespective of the ste
Epimerisation of 4-Acetoxyflavans and Flavan-4-ols
Attwood, Michael R.,Brown, Ben R.,Pike, William T.
, p. 2229 - 2236 (2007/10/02)
5,7,3',4'-Tetramethoxyflavan-4β-ol reacts at 0 deg C with pyridine, ang a trace of acetic acid to give the 4β-acetoxy derivative but at 90 deg C the 4α-acetoxyflavan is formed.Either acetate when equilibrated with this acetylating agent yields a mixture o
