César, Thaïs B.Manthey, John A.Myung, Kyung2022-04-282022-04-282009-09-25Journal of Natural Products, v. 72, n. 9, p. 1702-1704, 2009.0163-3864http://hdl.handle.net/11449/219526A new cyclic acetal (1) of marmin (6′,7′-dihydroxy-7- geranyloxycoumarin), two new cyclic acetals (5, 6) of 6′,7′- dihydroxybergamottin, and the known compounds marmin (2), 7-geranyloxycoumarin (3), bergamottin (4), and 6′,7′-dihydroxybergamottin (7) were isolated from grapefruit peel oil. All compounds were tested for inhibitory activity against intestinal cytochrome P450 3A4, an enzyme involved in the grapefruit/drug interactions in humans. Coumarins (1-3) exhibited negligible inhibitory activity, while the furanocoumarins (4-7) showed potent in vitro inhibitory activity with IC50 values of 2.42, 0.13, 0.27, and 1.58 μM, respectively.1702-1704engArtigo10.1021/np900266m2-s2.0-70349518908