Four new constituents from the fruits of Cyclocodon lancifolius (Roxburgh) Kurz.

Phytochemical analysis of the fruits of Cyclocodon lancifolius led to the isolation of two new phenylpropanoid-derived glycosides (1-2), two new geranyl glucosides (3-4), and nine known compounds (5-13). Their chemical structures were elucidated by extensive spectroscopic data. The absolute configuration of the sugar moiety was determined by hydrolysis and derivatization. All compounds were evaluated for their xanthine oxidase (XO) and α-glucosidase inhibitory activities, and four compounds showed weak inhibitory activity towards XO.

Synthesis and Bioactivity Evaluation of Nepetaefolin F and Its Analogues.

Nepetaefolin F (5), an abietane diterpenoid, showed significant inhibitory activity against human cancer cells in vitro with an IC50 value of 6.3 µM. The syntheses of nepetaefolin F and its analogues are presented herein. The cytotoxicity against various cancer cell lines was evaluated; notably, the cyclopropanecarboxylate ester 42 displayed significant antitumor activity against MGC 803 cells with an IC50 value of 20.9 µM. Further studies revealed that 42 could upregulate the expression of p62, microtubule-associated protein 1 light-chain 3 ß (LC3 B-I), cleaved caspase-3, and cleaved caspase-9 and downregulate the expression of Beclin-1 and LC3B-II. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that 42 could modulate multiple signaling pathways, especially for peroxisome proliferator-activated receptor (PPAR) and AMP-activated protein kinase (AMPK), which are closely related to autophagy. These results suggested that compound 42 is a promising lead by inhibiting cell proliferation and autophagy, as inducing cell apoptosis in MGC 803 cells.

Two pairs of epimers and three undescribed diterpenoids from Pseudocaryopteris paniculata.

A phytochemical investigation on the petroleum ether partition of the whole plant of Pseudocaryopteris paniculata, yield seven new compounds: one phytanes diterpenoid (2Z,6E,10E) 14-keto-2,6,10-trimethyl pentadeca-2,6,10-trien-1-carboxylic acid (1), five clerodane diterpenoids: paniculatins A-E (2, 3a/3b, 4a/4b), one abietane diterpenoid: ent-uncinatone (5), together with 12 known compounds. Their structures were elucidated on the basis of 1D and 2D Nuclear Magnetic Resonance （NMR_, Infrared Radiation (IR), and mass spectroscopic data. Compound 2, 5, and 11 showed weak selective cytotoxic activity of 11 human cancer cell lines.

Cytotoxic Diterpenoids from Caryopteris aureoglandulosa.

Seven new (1-7) and 11 known diterpenoids were isolated and identified from Caryopteris aureoglandulosa. These diterpenoids were structurally determined by HRESIMS and NMR spectroscopic analyses, single-crystal X-ray diffraction, and ECD data. Structurally, aureoglandulosin A (1) is a highly oxygenated abietane diterpenoid with an unprecedented 7/6/6/5-ring system. Aureoglandulosins B (2) and C (3) represent naturally occurring new diterpenoids with an unusual 6/6/6/5-ring system. Additionally, the configurations of two known abietane diterpenoids 11 and 12 were determined by X-ray crystallographic data analysis for the first time. A plausible biosynthetic pathway for compounds 1-3 is proposed. The cytotoxicity of all isolates was evaluated, and compounds 1 and 11 exhibited significant cytotoxic activity against some cell lines with IC50 values in the range 1.6-8.2 µM.

Caryopincaolide M, a rearranged abietane diterpenoid with new skeleton and a new iridoid from Caryopteris incana.

Caryopincaolide M (1), a new rearranged abietane diterpenoid with an unusual pent-4-enoic acid group on a 6/6/5 tricyclic ring system, and 7-epi-8-dehydroxypatriscabrol (3), a new iridoid, together with 17 known compounds, have been isolated from the whole plant of Caryopteris incana (Thunb.) Miq. Their structures were elucidated on the basis of 1-D and 2-D NMR, IR, and mass spectroscopic data. Compounds 1-5 were evaluated for their inhibitory activities against enzyme α-glucosidase, and the results showed that only 1 has moderate inhibitory activity against enzyme α-glucosidase with IC50 at 528.3 ± 12.37 mg/L.

Nepetaefolins A-J, Cytotoxic Chinane and Abietane Diterpenoids from Caryopteris nepetaefolia.

Nepetaefolins A-J (1-10) and seven known compounds were isolated from the whole plant of Caryopteris nepetaefolia. The absolute configurations of 1-3 were determined from single-crystal X-ray diffraction and spectroscopic data. Compounds 6 and 7, with IC50 values of 6.3-9.0 µM, showed higher cytotoxicity than paclitaxel in one non-small-cell lung cancer, patient-derived xenograft (PDX) model when tested using PDX models and the adenosine triphosphate-tumor chemosensitivity assay (ATP-TCA).

New Iridoid Glucosides from Caryopteris incana (Thunb.) Miq. and Their α-Glucosidase Inhibitory Activities.

In our continued investigations of the plant Caryopteris incana, five new iridoid glucosides 1-5, including two cis-trans-isomers, 3 and 4, along with six known compounds 6-11, were isolated from the n-butyl alcohol (n-BuOH) soluble fraction of whole dried material of Caryopteris incana. Their structures were established by a combination of spectroscopic techniques, including 1D and 2D NMR and high resolution electrospray ionization mass spectroscopy (HR-ESI-MS). Furthermore, all isolates were evaluated for their yeast α-glucosidase inhibitory effects. Among these compounds, 4-8 and 10 exhibited potent inhibition of α-glucosidase.