Hua-Yong Lou

Vulgarisin A, a new diterpenoid with a rare 5/6/4/5 ring skeleton from the Chinese medicinal plant Prunella vulgaris.

Vulgarisin A (1), a new diterpenoid with an unprecedented 5/6/4/5 fused tetracyclic ring skeleton, has been isolated from the medicinal plant Prunella vulgaris Linn. Its structure was characterized by extensive spectroscopic methods, and the absolute configuration was secured by single crystal X-ray diffraction analysis. Compound 1 showed weak cytotoxicity against human lung carcinoma A549 cells with an IC50 value of 57.0 μM.

A novel franchetine type norditerpenoid isolated from the roots of Aconitum carmichaeli Debx. with potential analgesic activity and less toxicity.

Further investigation on the phytochemistry of the plant Aconitum carmichaeli Debx. led to isolate a new franchetine type C(19)-diterpenoid alkaloid, guiwuline 1. Its structure was established on the basis of the spectroscopic data (1D and 2D NMR, HRESIMS, UV, IR). In mouse hot-plate test and acute toxicity assay, compound 1 exhibited potential analgesic activity (ED(50), 15 mg/kg) and showed little toxicity to mice (LD(50), 500 mg/kg). The results indicate that compound 1 may be used as a lead molecule to develop novel analgesic agents.

New cytochalasins from medicinal macrofungus Crodyceps taii and their inhibitory activities against human cancer cells.

Three new cytochalasins (1-3) together with two known cytochalasin analogues (4 and 5) were isolated from the chloroform fraction of ethanolic extract of a medicinal macrofungus Cordyceps taii. The structures of the new compounds were elucidated on the basis of spectroscopic analysis, including HRESIMS, 1D and 2D NMR experiments. The cytotoxicities of Compounds 1-5 were investigated by the sulforhodamine B (SRB) method in vitro against human highly metastatic lung cancer cell 95-D, human lung cancer cell line A-549 and normal hepatocyte HL-7702. The results revealed that Compounds 4 and 5 showed potent antitumor activities against human lung cancer cell 95-D with IC50 value of 3.67 and 4.04 μM, respectively. In comparison with cisplatin, the first-line chemotherapy drug, they had little or no cytotoxicity on normal cells, but showed stronger cytotoxic effects on cancer cells 95-D.

Syntheses and Anti-cancer Activities of Glycosylated Derivatives of Diosgenin

In order to obtain better anti-cancer compounds, nine glycosylated derivatives were designed and synthe-sized using diosgenin as starting material. Their structures were confirmed by 1H NMR, 13C NMR and MS spectra. The anti-cancer activities of intermediate compounds 5a—5i and the target compounds 6a—6i were investigated against human leukemia HEL, K562, HL60 and melanoma WM9 cell lines via MTT method. The bioassay results show that these derivatives possess good inhibitory activities against the four cancer cell lines. Furthermore, these derivatives show better inhibitory activities against K562 than against other cell lines, and most derivatives show better inhibitory activities than the parental material. Moreover, compounds 6a—6i are more active than their inter-mediates 5a—5i when against these cells. The above results demonstrate the effects of glycosylation on 3-OH of di-osgenin and acetylation of the sugar moiety on their antitumor activities.

C21 Steroidal Glycosides from Prunella vulgaris

GRAPHICAL ABSTRACT A new C21 steroidal glycoside, qinyangshengenin-3-O-β-D-digitoxopyranoside (1), together with a known steroidal glycoside, qinyangshengenin-3-O-β-D-oleandropyranosyl-(1→4)-β-D- cymaropyranosyl-(1→4)-β-D-digitoxopyranoside (2), was isolated from the medicinal plant Prunella vulgaris Linn. The structure of 1 was elucidated on the basis of extensive spectroscopic analysis, including HR-MS, 1D and 2D NMR experiments, and chemical evidence.

A new ecdysteroidal glycoside from Lepidogrammitis drymoglossoides (Bak.) Ching.

Lepidogrammitis drymoglossoides (Bak.) Ching is a medicinal plant that belongs to the family of Polypodiaceae. Previous phytochemical investigation on this genus had revealed the presence of flavonoids, sterols, and alkaloids. Here, further investigation on this medicinal plant led to the isolation of a new ecdysteroidal glycoside, ponasteroside B (1), along with a known steroidal compound, β-ecdysterone (2). The structure of 1 was determined on the basis of extensive spectroscopic analysis, including HR-MS and 1D and 2D NMR experiments, as well as a chemical hydrolysis study.

Design, Synthesis and Anticancer Evaluation of Fangchinoline Derivatives

Twenty fangchinoline derivatives were synthesized from the natural product fangchinoline, and their anticancer activities on human breast cancer MDA-MB-231 cell line, human prostate cancer PC3 cell line, human melanoma WM9 cell line and human leukaemia HEL and K562 cell lines were evaluated. The biological result showed that those derivatives exhibited potent activities on inhibiting cancer cell growth, and the structure-activity relationships were investigated. Among them, compound 4g, which was protected by benzoyl group in 7-phenolic position and nitrified in 14-position, showed impressive inhibition on all 5 cancer cell lines, especially WM9 cell line, with an IC50 value of 1.07 µM. Further mechanistic studies demonstrated that compound 4g may induce cancer cell death by apoptotic means. These research results suggested that compound 4g could be a lead for the further development toward an anticancer agent against human melanoma WM9 in the future.

Novel sesquiterpenoids isolated from Chimonanthus praecox and their antibacterial activities

In the present study, four new sesquiterpenoids, chimonols A-D (compounds 1-4), together with four known compounds (5-8) were isolated from the EtOAc extract of Chimonanthus praecox Link. The structures of these new compounds were elucidated on the basis of spectroscopic techniques (UV, IR, MS, and 1D and 2D NMR), and their absolute configurations were established by comparing experimental and calculated electronic circular dichroism (ECD) spectra. Compounds 1-8 were evaluated for antimicrobial activities and the minimum inhibitory concentrations (MICs) were determined by the broth microdilution method in 96-well culture plates. Compounds 1, 2, and 7 exhibited weak antibacterial effects for S. aureus (ATCC 6538), E. coli (ATCC 11775), and P. aeruginosa (ATCC 10145) with MIC values being 158-249 µg·mL-1. Compounds 3-7 showed activities against C. glabrata (ATCC 2001) and S. aureus (ATCC 43300) with MIC values being 128-197 µg·mL-1. Compounds 1-4 showed activity against S. aureus (ATCC 25923) with MIC values being 162-254 µg·mL-1. The present study provided a basis for future evaluation of these compounds as antibacterial agents.

Novel Flavones from the Root of Phytolacca acinosa Roxb.

Two new flavones, 6,7‐methylenedioxy‐4‐hydroxypeltogynan‐7′‐one (1), cochliophilin B (2), as well as two known ones, cochliophilin A (3) and 6‐methoxy‐7‐hydroxy flavone (4), were isolated from the ethanol extract of the root of Phytolacca acinosa Roxb. Compound 1 is a flavanol framework with one δ‐lactone unit, which is rather rare in nature. The structures of the new compounds were determined on the basis of extensive spectroscopic (IR, MS, 1D‐ and 2D‐NMR) analyses, the absolute configuration of 1 was established by comparing experimental and calculated electronic circular dichroism spectra. The structures of known compounds were fixed by comparison with literatures data. Compounds 2 and 4 showed modest inhibitory activities against BEL‐7402 cell line, with IC50 values of 28.22 and 39.16 μmol/L, respectively.