Phenols from the rhizome of Wikstroemia indica

A phytochemical investigation on the rhizome of Wikstroemia indica led to the isolation of thirteen phenolic compounds, including three flavonoids (1-3), three lignans (4-6), two coumarins (7, 8), one stilbene glycoside (9), one polyketide (10), one caffeoylquinic acid (11), one diarylpentanoid (12) and one benzoic acid derivative (13). The structural elucidation of these compounds was determined by using spectroscopic methods and by comparison with the literature. Compounds 2, 4, 5 and 12 were obtained from W. indica for the first time, and compounds 9-11 were firstly isolated from the family Thymelaeaceae. Furthermore, the chemotaxonomic significance of these compounds was discussed.