Qing-Jian Zhang

2-Arylbenzofuran derivatives from Morus cathayana.

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.

Cytotoxic Triterpenoid Saponins from Lysimachia clethroides

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.

Bioactive Sesquiterpenoids from the Rhizomes of Acorus calamus

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.

Four new N-contained iridoid glycosides from flower buds of Lonicera japonica.

Four new N-contained iridoid glycosides, lonijapospiroside A (1), l-phenylalaninosecologanin B (2), l-phenylalaninosecologanin C (3), and dehydroprolinoylloganin A (4), were isolated from the flower buds of Lonicera japonica Thunb. Their structures were established on the basis of UV, IR, MS, and NMR spectral data.

Steroidal alkaloids from the bulbs of Fritillaria unibracteata

Two new steroidal alkaloids peimisine-3-O-β-d-glucopyranoside (1) and puqiedinone-3-O-β-d-glucopyranoside (3), together with three known compounds peimisine (2), puqiedinone (4), and puqiedine (5), were isolated and characterized from the bulbs of Fritillaria unibracteata. Their structures were fully elucidated by spectroscopic and chemical methods. Compound 1 showed moderate protection effect on neurotoxicity of PC12 cell lines induced by rotenone.

Three new Diels-Alder type adducts from the stem bark of Morus cathayana.

Three new Diels–Alder type adducts cathayanons C (1), D (2), and E (3), together with one known compound sanggenon C (4), were isolated from the stem bark of Morus cathayana. Their structures were fully elucidated by spectroscopic and chemical methods. Compound 2 showed good anti-oxidation activity with the inhibitory rate of malondialdehyde being 88% at a concentration of 10− 6 mol/l.

Chemical constituents of the stem bark of Morus cathayana.

Phytochemical investigation of the stem bark of Morus cathayana led to the isolation and identification of six new compounds, cathayanons F–J (1–5) and cathayanin A (6), and two known compounds, cathayanins B–C (7–8). Their structures were elucidated by spectroscopic methods. Compounds 1, 2, 3, 5, and 7 exhibited weak activities against five human cancer cell lines, with IC50 values ranging from 4.7 to 9.8 μg/ml.

Four new flavonoids from Morus australis

Four new flavonoids, benzokuwanon E (1), hydroxymorusin (2), dicyclokuwanon EA (3), and dicyclokuwanon EB (4), were isolated from Morus australis. Their structures were elucidated on the basis of UV, IR, MS, NMR, and CD spectral data.

Two new dimeric stilbenes from the stem bark of Morus australis

Two new dimeric stilbenes austrafuran B (1) and austrafuran C (2) were isolated from the bark of Morus australis. Their structures were elucidated on the basis of spectroscopic methods.

Three new norsesquiterpenoids from the seeds of Alpinia galanga.

From the seeds of Alpinia galanga Willd., three new norsesquiterpenoid racemic mixtures, galanols A–C (1–3) were isolated, along with three known sesquiterpenoids (4–6). Their structures were elucidated by means of UV, IR, HR-ESI-MS, 1D NMR and 2D NMR spectroscopic data.