A new flavone from leaves of Nicotiana tabacum and its antibacterial activity / 中草药

ABSTRACT

Objective To find the new biological compounds, the research of the chemical constituents in the leaves of Nicotiana tabacum had been carried out. Methods The chemical constituents in the leaves of N.tabacum were isolated by silica gel, Sephadex LH-20 column chromatographies, and RP-HPLC methods. The structures of isolations were detected by using various spectroscopic techniques, including extensive 1D and 2D NMR techniques. Results Two C-alkylated flavones were isolated from 95% ethanol extract of plant, which identified as 2’-hydroxy-7-(3-hydroxypropyl)-8-methoxy-flavone (1) and tabaflavone A (2). Compounds 1 and 2 were evaluated for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. Conclusion Compound 2 is isolated from the leaves of N.tabacum for the first time. Compound 1 is a new compound named orientalflavone A. Compounds 1 and 2 also show good anti-MRSA activity with MIC90 value of (38 ± 4) and (33 ± 3) μg/mL, respectively.