Suggested Reaction 1.14.17.-

Left

1-Benzopyrylium, 3,5,7-trihydroxy-2-(4-hydroxyphenyl)-, chloride
+Vitamin C
+O2

Right

3,4',5,7-tetrahydroxyflavone
+Dehydroascorbate
+H2O

[BiSSCat | GREP ]