Isolation of new isoflavonoids derivatives from <i>Genista carinalis</i> Griseb. and biological activity

The genus <i>Genista</i> L. has been used in the treatment of rheumatic, diabetic and ulcerous diseases. Herein, the antioxidant, anticholinesterase, and antidiabetic activities of <i>Genista carinalis</i> Griseb. extracts were determined. The antioxidant activity was performed FRAP, DPPH, CUPRAC, and TEAC assays, while anticholinesterase activity was performed against acetylcholinesterase and butyrylcholinesterase, and antidiabetic activity against α-amylase and α-glucosidase, spectrophotometrically. The activity results allowed for the study of the phytochemistry of the ethyl acetate extract that exhibited the best activity. Three new isoflavonoids, 5-methyl-7-methoxy-4'-hydroxy isoflavone <b>(3)</b>, 7-acetyl-5-hydroxy-4'-methoxy isoflavone <b>(4)</b> and 7-O-[β-D-glucopyranosyl-(6''→6''')-β-D-glucopyranosyl]-5-4'-dihydroxy isoflavone <b>(5)</b>, together with two known compounds, isoprunetin <b>(1)</b> and 6-hydroxy biochanin A <b>(2)</b> were isolated from the ethyl acetate extract. Their structures were elucidated by extensive 1D-, 2D-NMR, and MS data analyses. Compound <b>(3)</b> showed the highest antioxidant potential in TEAC, FRAP, and CUPRAC assays, while <b>(2)</b> exhibited higher butyrylcholinesterase enzyme inhibitory activity among the isolated compounds.