Isoprenylated flavonoids from the roots of Sophora tonkinensis

Two new isoprenylated flavanones, tonkinochromanes J (1) and K (2), and a new isoprenylated dihydrochalcone, tonkinochromane L (3), were isolated from the roots of Sophora tonkinensis along with four known compounds (4-7). Their structures were determined by means of spectroscopic analyses, including HRMS, IR, 1H and 13C NMR and 2D experiments (COSY, HSQC, and HMBC), and comparison with known related compounds.