Conversion of procyanidin B-type (catechin dimer) to A-type: evidence for abstraction of C-2 hydrogen in catechin during radical oxidation

@article{Kondo2000ConversionOP,
  title={Conversion of procyanidin B-type (catechin dimer) to A-type: evidence for abstraction of C-2 hydrogen in catechin during radical oxidation},
  author={Kazunari Kondo and Masaaki Kurihara and Kiyoshi Fukuhara and Takashi Tanaka and Takashi Suzuki and Naoki Miyata and Masatake Toyoda},
  journal={Tetrahedron Letters},
  year={2000},
  volume={41},
  pages={485-488}
}
Abstract Procyanidin B-1 and B-2 were converted into A-1 and A-2 by radical oxidation using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals under neutral conditions, respectively. Transformation of procyanidin B-type into A-type certainly shows abstraction of the hydrogen atom at the C-2 position during radical oxidation. 
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