Figure 4. Selected key HMBC correlations in model of flavon (1), antosian (2), nonhydrolysable tannin (5), and hydrolysable tannin (6). COSY correlations in stilbenoid models (3-4)

From

Simplified Practical Identification of Polyphenol Types in Natural Dietaries Based on 1D and 2D Nuclear Magnetic Resonance

Azis Saifudin, Habibie Habibie, Muhammad Aswad, Yasuhiro Tezuka, Ken Tanaka

Journal of Food and Nutrition Research. 2023, 11(12), 742-751 doi:10.12691/jfnr-11-12-6