Zhi-Yong Jiang

Cytotoxic deoxybenzoins and diphenylethylenes from Arundina graminifolia.

Eight new C-4-alkylated deoxybenzoins (1-8), three new diphenylethylenes (9-11), and five known diphenylethylenes were isolated from Arundina graminifolia. The structures of 1-11 were elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques. Compounds 9-11 are the first naturally occurring diphenylethylenes possessing a hydroxyethyl unit. Compounds 1-11 were evaluated for cytotoxicity against five human tumor cell lines. Compounds 4, 5, and 9-11 showed significant cytotoxicity against five cancer cell lines, with IC50 values ranging from 1.8 to 8.7 μM.

New amide alkaloids from Piper longum

Bioassay-guided phytochemical investigation on Piper longum resulted in the isolation of two new compounds. By analyses of the MS, IR, UV, 1D and 2D NMR data, the two new compounds were identified as 3β, 4α-dihydroxy-1-(3-phenylpropanoyl)-piperidine-2-one (1) and (2E, 4E, 14Z)-6-hydroxyl-N-isobutyleicosa-2,4,14-trienamide (2). In vitro anti-HBV bioassay demonstrated compound 1 possessed remarkable activity suppressing the secretion of HBeAg in Hep G2.2.15 cell line, with an IC(50) value of 0.21mM and SI value of 16.4.

Acutissimanide, a new lignan with antioxidant activity isolated from the bark of Quercus acutissima Carruth

Acutissimanide (1), a new lignin, together with 11 known polyphenols (2–12) were isolated from the bark of the deciduous oak tree, Quercus acutissima Carruth. The structure of compound 1 was determined using multidimensional 1H and 13C NMR and mass spectroscopy. The antioxidant properties of compounds 1–12 were investigated using a 1,1-diphenyl-2-picryhydrazyl radical-scavenging assay with compounds 6–11 displaying significant antioxidant activity (EC50 values of 5.2–23.7 μM). Our findings suggest the extracts of Q. acutissima Carruth are a potential source of natural antioxidant additives for use in the food and other allied industries.

New Clerodane Diterpenes from Tinospora sagittata var. yunnanensis

Four new clerodane diterpenes, namely sagittatayunnanosides A-D (1-4), were isolated from the roots of Tinospora sagittata var. yunnanensis, together with two known compounds, tinospinoside C (5) and tinospinoside E (6). The structures of the four new compounds were well elucidated by extensive analyses of the MS, IR, and 1D and 2D NMR data. The cytotoxic and antifouling activities of compounds 1-6 were evaluated.

Five new prenylated chalcones from Desmodium renifolium

Five unusual new prenylated chalcones, renifolins D-H (1-5), were isolated from whole Desmodium renifolium plants. All of their structures were determined by spectroscopic methods including 1D and 2D NMR. All of the isolates were evaluated for cytotoxicity using five tumor cell lines. Compounds 2 and 3 exhibited cytotoxicity against A549 cells, with IC50 values of 2.8 and 2.2 μM, respectively.

Two New Sphingolipids from the Leaves of Piper betle L.

Two new sphingolipids, pipercerebrosides A (1) and B (2), were isolated from the leaves of Piper betle L. Their structures, including absolute configurations, were determined by spectroscopic analysis and chemical degradation. These two compounds did not show significant cytotoxic activity against the cancer cell lines K562 and HL-60 in a MTT assay.

Two new biphenyls from the stems of Garcinia tetralata

Abstract Two new biphenyls (1 and 2) and three known xanthones (3–5) were isolated from the ethanol extract of the stems of Garcinia tetralata. Structural elucidations of 1–2 were elucidated by spectroscopic methods including extensive 1D- and 2D-nuclear magnetic resonance spectroscopy techniques. Compounds 1–2 showed anti-rotavirus activities with SI above 10.

Four New Diterpene Glucosides from Perovskia atriplicifolia

Four new diterpene glucosides, namely perovskiaditerpenosides A – D (1 – 4), were isolated from the BuOH extract of Perovskia atriplicifolia. Their structures were well elucidated by chemical methods and comprehensive spectroscopic analyses including MS, IR, and NMR (1D and 2D). The newly isolated compounds were screened for their cytotoxic activity against HepG2, NB4, HeLa, K562, MCF7, PC3, and HL60. The obtained results indicated that the new compounds possessed considerable cytotoxic activity.

Cytotoxic Diterpenoids from the Roots of Aralia melanocarpa.

Five new diterpenoids (1-5) were isolated from the roots of Aralia melanocarpa, together with four known compounds, 7β-hydroxy-ent-pimara-8(14),15-diene-19-oic acid (6), 18-norpimara-8(14),15-dien-4-ol (7), ent-16βH,17-isovalerate-kauran-19-oic acid (8), and ent-16α,17-dihydroxykauran-19-oic acid (9). Based on the MS, IR, and NMR spectral analysis, the structures of the five new diterpenoids (1-5) were elucidated. The cytotoxic activities of compounds 1-9 were assayed, and compounds 1 and 2 showed cytotoxicity in four cancer cell lines with IC50s from 4.2 to 8.2 µM.

New Biphenyls from Garcinia multiflora

Three new biphenyls were isolated from Garcinia multiflora. The structures of these biphenyls were elucidated by spectroscopic methods, and their rotavirus activity was evaluated.