A novel bis-furan derivative, two new natural furan derivatives from Rehmannia glutinosa and their bioactivity.

A novel bis-furan derivative and two new natural furan derivatives were isolated from the CHCl3 extracts of the dried roots of Rehmannia glutinosa (Gaerth) Lilosch. Their structures were identified as 1,5-bis(5-methoxymethyl)furan-2-yl-penta-1,4-dien-3-one 1, (E)-4-(5-(methoxymethyl)furan-2-yl)but-3-en-2-one 2 and (E)-4-(5-(hydroxymethyl)furan-2-yl)but-3-en-2-one 3 on the basis of spectral data. Moreover, biological assay showed that 1 (10 microg/mL) and 3 (10 microg/mL) can promote immune activity, 2 (100 microg/mL) and 3 (100 microg/mL) inhibit immune activity and 1 can inhibit blood platelet aggregation.