Bioactive Glycosides from the Twigs of Litsea cubeba

Abstract

The air-dried twigs of Litsea cubeba, a traditional Chinese medicinal tree, afforded 10 new aromatic glycosides (1-10) and 26 known analogues. Their structures were assigned by extensive 1D and 2D NMR experiments, and the absolute configurations were resolved by chemical methods, electronic circular dichroism, specific rotation, and X-ray crystallographic analysis. Compound 4 is the first example of a naturally occurring homoneolignan glucoside. Compounds 4, 6-8, and the known neolignan glucosides (11, 12, and 14) at respective 10 μM concentrations were found to reduce acetaminophen-induced HepG2 cell injury with 30.5-46.0% inhibitions. Furthermore, compounds 12 and 15 demonstrated moderate inhibitory activities against HDAC1, with IC values of 3.6 and 4.6 μM, respectively.

Lignans from the Twigs of <em>Litsea cubeba</em> and Their Bioactivities

“…Cytotoxicity assay found that fraction F9 displayed potent activities against HCT-116, NCI-H1650, and A270 cell lines. Isolation of fraction F9 by Sephadex LH-20, RP-18, preparative TLC, and preparative HPLC led to the discovery of nine new lignans (1)(2)(3)(4)(5)(6)(7)(8)(9) and ten known ones (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)). Compound 1 was obtained as a white amorphous powder.…”

“…In summary, bioassay-guided isolation of cytotoxic fractions of the twigs of L. cubeba revealed the presence of nine new lignans (1-9) and ten analogues (10)(11)(12)(13)(14)(15)(16)(17)(18)(19). Initially, all of the isolated compounds were evaluated against HCT-116, NCI-H1650, and A2780 tumor cell lines.…”

“…cubeba twigs by our group led to the characterization of 36 aromatic glycosides from the water-soluble fraction of an ethanolic extract. Interestingly, some lignan glycosides showed potent hepatoprotective and HDAC1 inhibitory activity [16][17]. In the present study, we have investigated the constituents of the EtOAc-soluble fraction of the ethanolic extract of L. cubeba twigs.…”

“…In the present study, we have investigated the constituents of the EtOAc-soluble fraction of the ethanolic extract of L. cubeba twigs. Bioassay-guided isolation of a fraction with cytotoxicity against HCT-116, NCI-H1650, and A2780 cell lines (IC50 = 28.3, 11.5, and 16.8 µ g/mL, respectively) led to the discovery of nine new lignans (1)(2)(3)(4)(5)(6)(7)(8)(9) and eleven analogues (10)(11)(12)(13)(14)(15)(16)(17)(18)(19) ( Figure 1). The structures of 1-9 were elucidated by spectroscopic methods, and their absolute configurations were determined by optical rotations and a combination of experimental and theoretically calculated electronic circular dichroism (ECD) spectra.…”

Lignans from the Twigs of Litsea cubeba and Their Bioactivities

“…Since there are few reports on the phytochemicals of twigs of L. cubeba , a recent study on L. cubeba twigs by our group led to the characterization of 36 aromatic glycosides from the the water-soluble fraction of an ethanolic extract. Interestingly, some lignan glycosides showed potent hepatoprotective and HDAC1 inhibitory activity [16,17]. In the present study, we have investigated the constituents of the EtOAc-soluble fraction of the ethanolic extract of L. cubeba twigs.…”