Sinningia allagophylla, found in Brazil, Paraguay and Argentina, is used by the Brazilian population as diuretic, febrifuge, depurative, and tonic. We present the isolation of nine compounds (1-9) from its tubers, four of them being new: two dimeric naphthochromenes, allagophylldimer D (1) and allagophylldimer E (2); a coumarin, 6,8-dimethoxybenzocoumarin (3); and a naphthoquinone-derivative, allagophyllone (4). The known compounds were identified as α-isodunnione (5), warmingiin A (6), warmingiin B (7), cleroindicin B (8), and cleroindicin C (9). All compounds were analyzed by 1D and 2D NMR, and HRMS spectra were recorded for the new compounds. Additionally, conformational analyses were carried on compounds 1 and 2. Compound 5 had been previously obtained only by synthesis, and its complete NMR data are presented here.
Dimeric naphthochromenes and other constituents of Sinningia allagophylla (Gesneriaceae)
Publication: Phytochemistry Letters