Two new cyclobutane-type norlignans, methyl rel-(1R,2S,3S)-2-(7-methoxy-1,3-benzodioxol-5-yl)-3-(2,4,5-trimethoxyphenyl)cyclobutanecarboxylate (1), and methyl rel-(1R,2R,3S)-2-(7-methoxy-1,3-benzodioxol-5-yl)-3-(2,4,5-trimethoxyphenyl)cyclobutanecarboxylate (2), and a new lignanamide, 3-hydroxy-N-[2-(4-hydroxyphenyl)ethyl]-α-[4-(2-{N-[2-(4-hydroxyphenyl)ethyl]carbamoyl}ethenyl)-3-methoxyphenoxy]-4-methoxycinnamamide 4,8″-ether (3), along with five known amides, 4–8, were obtained from the whole plant of Peperomia tetraphylla. Their structures were elucidated mainly by the analysis of NMR and MS data. The new compounds 1–3 and the known compound 4 were tested for their cytotoxic activities against the HepG2 (human hepatocarcinoma), A549 (human lung cancer), and HeLa (human cervical cancer) cell lines. Compound 4 showed significant cytotoxicity against HepG2 cell lines with an IC₅₀ value of 9.4±1.0 μM.

Three new bisabolocurcumin ethers, named demethoxybisabolocurcumin ether (1), bisabolocurcumin ether (2), and didemethoxybisabolocurcumin ether (3), along with two known compounds, 4 and 5, were isolated from the AcOEt extract of the rhizomes of Curcuma longa L. Their structures were established by the analysis of NMR and MS data. The new compounds 1–3, which possess a new 1,7-diarylheptanoid skeleton linked with a bisabolone-type sesquiterpene substructure by a CO bond, were found for the first time in a natural source.

Two new homo-aro-cholestane glycosides and a new cholestane glycoside, along with three known saponins, were isolated from the 95% EtOH extract of the roots and rhizomes of Paris polyphylla var. pseudothibetica. The structures of the new compounds were elucidated as 3β-O-{α-L-rhamnopyranosyl-(14)-α-L-rhamnopyranosyl-(14)-[α-L-rhamnopyranosyl-(12)]}-β-D-glucopyranosylhomo-aro-cholest-5-ene-26-O-β-D-glucopyranoside (parispseudoside A, 1), 3β-O-α-L-rhamnopyranosyl-(12)-β-D-glucopyranosylhomo-aro-cholest-5-ene-26-O-β-D-glucopyranoside (parispseudoside B, 2), and (25R)-3β-O-{α-L-rhamnopyranosyl-(14)-α-L-rhamnopyranosyl-(14)-[α-L-rhamnopyranosyl-(12)]}-β-D-glucopyranosyl-cholesta-5,17(20)-diene-16,22-dione-26-O-β-D-glucopyranoside (parispseudoside C, 3) by spectroscopic methods, including 1D- and 2D-NMR, and MS experiments, as well as chemical evidences.

Two new kaempferol glycosides, 5-hydroxy-2-(4-hydroxyphenyl)-4-oxo-7-(α-L-rhamnopyranosyloxy)-4H-chromen-3-yl 2-O-acetyl-3-O-β-D-glucopyranosyl-α-L-rhamnopyranoside (1) and 5-hydroxy-2-(4-hydroxyphenyl)-4-oxo-7-(α-L-rhamnopyranosyloxy)-4H-chromen-3-yl β-D-glucopyranosyl-(12)-6-O-[(2E)-3-(4-hydroxyphenyl)prop-2-enoyl]-β-D-glucopyranosyl-(12)-β-D-glucopyranoside (2), along with ten known compounds, were isolated from the 95% EtOH extract of the whole plant of Androsace umbellata. The structures of the new glycosides were determined on the basis of detailed spectroscopic analyses, including 1D- and 2D-NMR, MS, and chemical methods.