322
Favan
Flavanone Flavone
FlavonolDihydroflavonol
Flavan-3-ol
Flavan-4-ol
Favan-3,4-diol
*stereoisomers
Anthocyanins
Flavonols
B-type procyanidins
A-type procyanidins
O
*
A
C
B
O
O
*
O
O
O
O
OH
O
OH
*
*
O
OH
*
*
O
OH
*
*
O
OH
OH
*
*
O
HO
OH
R 1
OH
R 2
O
O
HO
OH
OR 3
OH
+
O
HO
OH O
OR 3
R 1
OH
R 2
4
8
OH
R1
R2
O
R1
OH
HO
OH
O
OH
OH
HO
OH
R2
O
OH
HO
R 2
R 1
HO
OH
2
OH
R 2
O
R 1
OH
HO
OH
4
6
OH
R 2
O
R 1
OH
HO
OH
R 2
OH
O
OH
OH
O
R 1
2
7
4
8
Fig. 11.3 Structures of various flavonoid groups
V. I. Petropulos and B. Balabanova