62861-00-1Relevant academic research and scientific papers
Oligomeric flavanoids. Part 19. Reductive cleavage of the interflavanyl bond in proanthocyanidins
Steynberg, Petrus J.,Steynberg, Jan P.,Bezuidenhoudt, Barend C. B.,Ferreira, Daneel
, p. 3005 - 3012 (2007/10/03)
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.
Oligomeric flavanoids. Part 17a. Absolute configurations of flavan-3-ols and 4-arylflavan-3-ols via the Mosher method
Rossouw,Hundt,Steenkamp,Ferreira
, p. 12477 - 12488 (2007/10/02)
1H NMR analysis of R-(+)- and S-(+)-α-methoxy-α-trifluoromethylphenyl acetic acid (MTPA) esters of flavan-3-ols and 4-arylflavan-3-ols permits assessment of the absolute configurations at C-3 of these condensed tannin structural units.
Cleavage of the Interflavanyl Bond in 5-Deoxy (A Ring) Proanthocyanidins
Steynberg, Petrus J.,Steynberg, Jan P.,Bezuidenhoudt, Barend C. B.,Ferreira, Daneel
, p. 31 - 32 (2007/10/02)
The fisetinidol-(4,8) and (4,6)-catechin profisetinidin biflavonoids 1, 4 and 5 respectively, are subject to facile cleavage of the interflavanyl linkage with sodium cyanoborohydride in trifluoroacetic acid at 0 deg C.
