Recent Advances in Polyphenol Research. Группа авторов
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Chemistry, 37: 5617–5626.
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Endnotes
1 1 In previous work we have used the term mono ionized, in the sense of formation of ions. This was the term used for ions resulting from the acid‐base reactions and the respective constants were defined as ionization constants.
2 2 In any case, both processes are well separated in time and the respective amplitude can be obtained.
3 3 In the case of 4’‐hydroxyflavylium the trans‐chalcones are almost 100% of CB and thus equilibrium is achieved with AH+ and the trans‐chalcones.
4 4 Flash photolysis is applied when there is excited state flavylium/quinoidal base proton transfer.
5 5 In the case of two derivatives bearing one acylated unit, the compound with the three glucoside units has the highest effect.
6 6 It is possible to observe the blue color at pseudo‐equilibrium in other systems. The peculiar behavior of HBA1 is that the purplish and blue colors are observed at equilibrium.
7 7 In principle, other analytical techniques, such as nuclear magnetic resonance (NMR), can be used to access the ratio FLV/Ct. The timer can be used only for a certain time interval (a few hours), because the spectral variations at the end of the reaction become very small.
2 Proanthocyanidin Oligomers with Doubly Linked (A‐Type) Interflavan Connectivity : Structure and Synthesis
Ken Ohmori and Keisuke Suzuki
Department of Chemistry, Tokyo Institute of Technology, Japan
Keywords: A‐type, afzelechin; catechin; epiafzelechin; epicatechin; flavan; flavonoid; oligomer; proanthocyanidin; procyanidin;
2.1 Introduction
The oligomeric proanthocyanidins (PAs),