The Chemical Constituents From The Roots Of Linum Usitatissimum L. And Paeonia Lactiflora Pall.

Linium usitatissimum L, is a plant widely occurring in most pars of China. Its roots, as a folk medicine, have been used for the treatments of chronic hepatitis, orchitis, etc., for a long tiem. But up to now, there are no reports on its chemical constituents and pharmacological activities. To find its active principles, the chemical constituents of the roots of L. usitatissimum were studied. 5 compounds were isolated by extracting with ethanol, a series of chromatographic separations and purifications on silica gel and recrystallizations. Their structures were identified by NMR and MS data as well as chemical method as Linum cerebroside A (1), 1-O-β-D-glucopyranosyl-(2S, 3R, 4E, 8Z)- 2[(2 (R)-hydroxyhexadecanoyl) amido]-4,8-octadecadiene-l,3-diol(2), daucosterol (4), eicosanoic acid (5) and ent-kaurane-3-oxo-16α-17-diol (6). Among them, compound 1 is a new one and compounds 2 and 6 were isolated from the plant for the first time. Furthermore, compounds land 2 exhibit some protective effects on the damage of liver induced by CCl₄, indicating that 1 and 2 are probably the active principles of the roots of L. usitatissimum.To obtain the reference substances from the roots of Paeonia lactiflora Pall for the establishment of its fingerprint by HPLC in the subsequent research, the chemical constituents of the roots were investigated. Except for 3 known monoterpenoids, paeoniflorin (9), albiflorin (10) and lactifiorin (11), another two analogs were isolated from the roots, namely neoalbilforin (7) and paeonivayin (8), along with benzoic acid (12) and stearic acid (13). Compound 7 was obtained for the first time as a natural product; compounds 8 and 13 were isolated for the first time from this pant. Due to the lack of NMR data of compound 7 in literature, extensive 1D, 2D NMR experiments were conducted to get the full assignments of its ¹H- and ¹³C-NMR signals. In the same time, the ¹H- and ¹³C-NMR signals of 8 (in CD₃COCD₃) were also fully assigned by 1D, 2D NMR experiments.