7he PHR spectra (Table i) characterize the different positions of the substituents in the phenol part of the ketones (I). Ihe OH groups occur at the position 2 (12.3-11.6 ppm) and 4 (10.7-9.5 ppm) of the phenol part of the moelcule, the aromatic protons of which form an ABX spin system with the Js, 6 of 8 Hz and the J~, 5 of 2 Hz; this corresponds with the coupling constants of the protons in the o-and m-positions. The signal of the 6-H proton is ...
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