New Alkaloid and Sesquiterpenoid From the Leaves of Cinnamomum bejolghota

From the leave of Cinnamomum bejolghota (Buch.‐ Ham. ex Nees) Sweet, one new alkaloid, 3,6‐dimethoxy‐9H‐pyrido[3,4‐b]indole ( 1 ) and one new aromadendrane sesquiterpenoid, 4 α ,10 α ‐dihydroxyaromadendrane‐13‐oic acid ( 2 ) along with seven known compounds, 4 β ,10 α ‐dihydroxyaromadendrane ( 3 ), litseachromolaevane A ( 4 ), curcumin ( 5 ), pisumionoside ( 6 ), quercetin‐3‐ O‐α ‐L‐rhamnopyranoside ( 7 ), rutin ( 8 ), and kaemperol 3‐ O ‐neohesperidoside ( 9 ) were isolated and structurally determined. Their chemical structures were elucidated through comprehensive spectroscopic analyses, including high‐resolution electrospray ionization mass spectrometry, one‐ and two‐dimensional nuclear magnetic resonance, and by comparison with the literature data. Compounds 1–9 were evaluated for their cytotoxic activities against four human cancer cell lines (KB, MCF‐7, HepG‐2, and SK‐LU1), however, only compound 8 displayed weak inhibitory activity on HepG2, A549 cancer cell lines with 50% inhibitory concentration (IC 50 ) values of 97.8 and 68.8 µM, respectively and moderate inhibitory activity on MCF7 cancer cell line with an IC 50 value of 49.7 µM.