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Six new iridal-type triterpenoids containing an unprecedented cyclopentane ring, polycycloiridals E-J (1-6), were isolated from a large-scale re-extraction of Iris tectorum. A possible biosynthesis pathway is postulated. The known spirioiridotectal D (7) was also obtained in the current investigation, and its structure was unequivocally defined using X-ray diffraction data. Compound 7 suppressed LPS-activated NO production in the BV2 cell line with an IC 50 value of 0.54 μM.

Nine new iridoid glycosides, rehmachingiiosides A-I (1-9), together with 16 known analogues, were isolated from the whole plants of Rehmannia chingii. The structures of compounds 1-9 were elucidated on the basis of spectroscopic data analysis and from chemical evidence. Furthermore, in two vitro assays, compounds 5 and 10 showed an inhibitory effect on LPS-induced NO production with IC50 values of 2.5 and 7.3 μM, and compounds 4, 6, and 10-12 (when evaluated at 10 μM) exhibited evidence of hepatoprotective effects against APAP-induced HepG2 cell damage.

Six novel iridal-type triterpenoids with a previously unreported 3,6-dihydro-2H-pyran moiety, named spirioiridotectals A-F (1-6), were isolated from the ethanol extract of the rhizomes of Iris tectorum. Their structures were elucidated on the basis of extensive spectroscopic analysis. Furthermore, in in vitro bioactivity assays, compounds 1, 2, and 6 exhibited neuroprotective activities against serum-deprivation-induced PC12 cell damage.

Seven new triterpenes, inonotusol A-G (1-7), one new diterpene, inonotusic acid (8), and 22 known compounds were isolated from Inonotus obliquus. Their structures were elucidated on the basis of spectroscopic analysis, including homonuclear and heteronuclear correlation NMR ((1)H-(1)H COSY, ROESY, HSQC, and HMBC) experiments. In in vitro assays, compounds 6 and 8-16 showed hepatoprotective effects against d-galactosamine-induced WB-F344 cell damage, with inhibitory effects from 34.4% to 81.2%. Compounds 7, 17, and 18 exhibited selective cytotoxicities against KB, Bel-7402, or A-549 cell lines. Compounds 16 and 17 showed inhibitory effects against protein tyrosine kinases, with IC50 values of 24.6 and 7.7 μM, respectively.

Chemical investigation of the seeds of Prunus davidiana afforded seven new aromatic glucosides, i.e., the prupersins A-E (1-5) and compounds 6 and 7, as well as 11 known compounds. The structures of 1-7 were elucidated by spectroscopic data analysis and chemical evidence, and configurations were determined by hydrolysis experiments (1, 2, and 5) or electronic circular dichroism (6). Compounds 1-6 exhibited antioxidant activity aganist Fe²⁺-cysteine-induced rat liver microsomal lipid peroxidation, with malondialdehyde inhibitory rates of 50-67% and 53-57% at concentrations of 10⁻⁵ and 10⁻⁶ mol/L, respectively.

Eleven new iridoid glycosides, rehmaglutosides A-K (1-11), together with 20 known analogues were isolated from the air-dried roots of Rehmannia glutinosa. The structures of these compounds were elucidated on the basis of spectroscopic data analysis and chemical evidence. Furthermore, in in vitro assays, compounds 3, 7, and 9-11 (10 μM) exhibited moderate hepatoprotective activities against D-galactosamine-induced HL-7702 cell damage.

Eight new sesquiterpenes (1-8) and one new norsesquiterpene (9) named calamusins A-I were isolated from the ethanol extract of Acorus calamus rhizomes. The absolute configuration of compound 8 was determined by comparing its experimental and calculated ECD spectra. The absolute configurations of the other compounds were determined from their CD spectra. Furthermore, in in vitro assays, compounds 3, 4, 7, and 9 (10 μM) exhibited weak hepatoprotective activities against APAP-induced HepG2 cell damage.

Seven oleanane-type triterpenoid saponins, named clethroidosides A-G (1-7), an ursane-type triterpenoid saponin, clethroidoside H (8), and six known saponins were isolated from the aerial parts of Lysimachia clethroides. The structures of the saponins were elucidated on the basis of physical data analysis (1D and 2D NMR, HR-ESIMS) and chemical evidence. The cytotoxic activities of compounds 1-14 were evaluated against five human tumor cell lines (HT-29, HePG2, BGC-823, A549, and A375). Compounds 3, 4, 6, and 11-13 exhibited moderate cytotoxic activity, with IC50 values of 0.75-2.62 μM, while compound 5 showed selective cytotoxic activity.

Eight new phenylpropanoid derivatives [quiquesetinerviusides A (1), B (2), C (3), D (4), and E (5), as well as quiquesetinerviusins A (6), B (7), and C (8)] and seven known compounds (8-15), were isolated from an EtOAc extract of Calamus quiquesetinervius stems. The structures of 1-8 were elucidated on the basis of 1D- and 2D-NMR spectroscopic data analysis. Bioassay results showed that 1-5 possess weak DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging activity, but potent (·)OH radical scavenging activity (IC(50) 3.6-8.4 μM). Of the tested isolates, compounds 4-6 and 9 showed potent inhibition (IC(50) 9.2-29.5 μM) of LPS-stimulated NO production when compared with a positive control substance, quercetin (IC(50) 34.5 μM).

Four new 2-arylbenzofuran derivatives, cathafurans A (1), B (2), C (3), and D (4), were isolated from the stem bark of Morus cathayana. Their structures were determined by spectroscopic methods. Compounds 2 and 3 exhibited moderate activities against five human cancer cell lines, with IC(50) values ranging from 6.17 to 9.60 microg/mL.

Six new diterpenoids, 7beta,8alpha-dihydroxy-12-oxo- ent-abietan-16,14-olide ( 1), 3,4,18beta-cyclopropa-7beta,17-dihydroxy- ent-abieta-8(14),13(15)-dien-16,12-olide ( 2), 3alpha,7beta-dihydroxy- ent-abieta-8(14),13(15)-dien-16,12-olide ( 3), 3-oxo-8beta,14beta-epoxy- ent-abieta-11,13(15)-dien-16,12-olide ( 4), 17-hydroxy- ent-pimara-8(14),15-dien-3-one ( 5), and 3alpha,6beta-dihydroxy- ent-kaur-16-ene ( 6), and two known compounds, 7beta-hydroxy- ent-abieta-8(14),13(15)-dien-16,12-olide ( 7) and jolkinolide B, were isolated from roots of Suregada glomerulata. The structures of the new compounds were elucidated on the basis of 1D and 2D NMR and other spectroscopic studies. The structure of compound 1 was confirmed by X-ray crystallography. Cytotoxic activities were evaluated against five human tumor cell lines.

Six new styrylpyrone derivatives, goniolactones A-F (1-6), have been isolated from the roots of Goniothalamus cheliensis. The structures and stereochemistry of the new compounds were elucidated by interpretation of spectroscopic data and chemical methods. The relative configuration of goniolactone A (1) was determined by X-ray crystallography analysis, and the absolute configurations of goniolactones A (1) and B (2) were established by Mosher's method. Goniolactone B (2) exhibited significant cytotoxicity against A2780, HCT-8, and KB cells with IC(50) values of 7.40, 4.43, and 7.23 microM, respectively.

Five new diprenylated flavonols, broussonol A (1), broussonol B (2), broussonol C (3), broussonol D (4), and broussonol E (5), along with two known compounds, were isolated from an ethanolic extract of the leaves of Broussonetia kazinoki. Their structures were elucidated by chemical and spectral methods. Cytotoxic activities were evaluated against several different cell lines.

Five new annonaceous acetogenins, calamistrins C-G (1-5), were isolated from an ethanolic extract of the roots of Uvaria calamistrata. Compounds 1-3 were mono-THF ring acetogenins; compounds 4 and 5 were bis-THF acetogenins, with the THF rings from C-18 to C-25. The absolute configurations of 3, 4, and 5 as well as the partial absolute configurations of 1 and 2 were determined by (13)C NMR spectroscopy and advanced Mosher methodology.

Lanceolatic acid (1), a new bislabdane-type diterpenoid, has been isolated from the roots of Cunninghamia lanceolata. Its structure was elucidated on the basis of spectroscopic data interpretation and confirmed by single-crystal X-ray diffraction analysis.

Three new alkaloids-griffithazanone A (1), griffithdione (2), and griffithinam (3)-were isolated from the roots of Goniothalamus griffithii, along with six known compounds, 4-methyl-2,9, 10-(2H)-1-azaanthracenetrione (4), velutinam, aristololactam BI, aristololactam BII, aristololactam AII, and norcepharanone B. Their structures were elucidated on the basis of spectral and chemical methods. The absolute configuration of griffithazanone A (1) was determined by the preparation of Mosher's esters.

Two new bioactive monotetrahydrofuran acetogenins, calamistrins A (1) and B (2), and two known compounds, uvarigrin (3) and uvarigranin (4), have been isolated from the roots of Uvaria calamistrata. The structures of the new compounds were elucidated by spectroscopic and chemical methods. The absolute stereochemistry of the stereogenic centers was established by Mosher ester methodology.

A novel Annonaceous acetogenin, donnaienin (1), was isolated from the roots of Goniothalamus donnaiensis. Its structure and stereochemistry were elucidated on the basis of spectral data and chemical evidence. This compound represents an unusual type of Annonaceous acetogenin, bearing a hydroxylated tetrahydrofuran ring.