Guogang Zhang

A new cerebroside from Gynura divaricata

A new cerebroside (1) was isolated from the aerial parts of Gynura divaricata DC., along with five known compounds: kaempferol (2), kaempferol 3-O-glucoside (3), kaempferol 3-O-rhamnosyl(1 → 6)glucoside (4), β-sitosteryl glucoside-6′-O-heptadecoicate (5) and 2-(1′, 2′, 3′, 4′-tetrahydroxybutyl)-6-(2″, 3″, 4″-trihydroxybutyl)-pyrazine (6), which are isolated for the first time from this species. The structure of 1 was determined to be 1-O-β-D-glucopyranosyl-(2S, 3S, 4R, 10Z)-2-[(2′R)-2′-hydroxylignocenoyl-amino]-10-octadecene-1,3,4-triol on the basis of chemical and spectroscopic evidence.

New naphthoquinone from the root of Lygodium japonicum (Thunb.) Sw.

A new 1,4-naphthoquinone and three known compounds were isolated from the roots of Lygodium japonicum (Thunb.) Sw. The structure of the new compound was elucidated by two-dimensional nuclear magnetic resonance and other spectral examinations.

Two new compounds from the roots of Ilex pubescens and their cytotoxic activity

A new phenylethanoid, 1-O-β-d-(4-hydroxyphenyl)-ethyl-6-O-vanilloyl-glucopyranoside (1), and a new furofuran lignan, (7R,7′R,7′′S,8S,8′S,8′′R)-4′, 4′′-dihydroxy-3,3′,3′′,5-tetramethoxy-7,9′:7′9-diepoxy-4,8′′-oxy-8,8′-sesquineolignan-7′′,9′′-diol (2), along with five known compounds (3–7) were isolated from the roots of Ilex pubescens. Their chemical structures were elucidated on the basis of extensive spectroscopic analysis, including UV, IR, MS, and NMR experiments. In addition, compounds 2–7 were evaluated in vitro for their cytotoxic effects on human HeLa cells; among them, compounds 2, 3, 6, and 7 showed cytotoxic activity against HeLa cells in the test.

A new ecdysteroside from Lygodium japonicum (Thunb.) Sw.

A new ecdysteroside, named lygodiumsteroside A, as well as a known ecdysteroside, were isolated from the roots of Lygodium japonicum (Thunb.) Sw. Their structures were identified by spectral and chemical methods.

A new compound from Lygodium japonicum (Thunb.) Sw.

A new ecdysteroside was isolated from the roots of Lygodium japonicum (Thunb.) Sw. The structure was identified as 2β,3β,14α,20R,22R-pentahydroxy-24R-methyl-5β-cholest-7-en-6-one-3-O-β-D-glucopyranoside by spectral and chemical methods.

A new arylbenzofuran from the aerial parts of alfalfa

A new arylbenzofuran, 4-hydroxy-2-(4′-hydroxy-2′-methoxyphenyl)-6-methoxybenzofu-ran-3-carbaldehyde (1), was isolated from the aerial parts of alfalfa (Medicago sativa L.), together with three known compounds. The structure of the new compound (1) was determined by spectroscopic methods.

Two new secoiridoid glucosides and a new lignan from the roots of Ilex pubescens

Two new secoiridoid glucosides, ilexpublignoside (1), pubzenoside (2), and a new lignan, ilexlignan B (3), along with seven known compounds (4–10) were isolated from the roots of Ilex pubescens for the first time. Their chemical structures were elucidated on the basis of extensive spectroscopic methods, including IR, UV, HR-ESI–MS, CD, NMR experiments, as well as comparison with the reported data.