Samuel X. Qiu

A new coumarin from Sarcandra glabra

Sarcandracoumarin (1), the first coumarin having a 1-phenylethyl substituent at the C-3 position, was isolated along with eleven known phenolic compounds from the water extract of Sarcandra glabra. Its structure was elucidated on the basis of spectroscopic data. Compound 1 exhibited moderate or weak cytotoxicity against several tumor cell lines.

Two new lignans from the stems of Schisandra bicolor.

Two new lignans, named zuihonins E (1) and F (2), were isolated from the stems of Schisandra bicolor Cheng var. tuberculata Law. The structures of the new lignans were elucidated on the basis of extensive spectroscopic analysis, including 1D, 2D NMR, and MS experiments, and their absolute stereochemistry was determined by circular dichroism spectrum. Compounds 1 and 2 did not inhibit the growth of hepatoma carcinoma cell (HepG2), lung carcinoma cell (A549), and human breast carcinoma (MCF-7) cell lines.

A new flavanocoumarin from the root of Flemingia philippinensis

One new flavanocoumarin, flemicoumarin A (1) was isolated from the EtOAc-soluble partition of the root of Flemingia philippinensis, along with three known compounds, namely 4,2′-epoxy-4′,5-dihydroxy-7,5′-dimethoxy-3-phenylcoumarin (2), kaempferol 6-C-glucoside (3) and dracocephaloside (4). The structure of compound 1 was elucidated on the basis of its 1D, 2D NMR, CD and MS data. The structures of the known compounds were identified by comparison of their spectroscopic data with those reported in the literature. Compounds 1–4 exhibited inactivity against MCF-7, A549 and Hep-G2 human cancer cell lines in vitro by MTT colorimetric assay.

A New Isoprenylated Flavanone from Cajanus cajan

A new isoprenylated flavanone, naringenin-3′-isoprenyl-7-methyl ether, was isolated from the chloroform extract of the leaves of Cajanus cajan. Its structure was eluciated by spectral analysis, mainly 1D and 2D NMR.