New Alkaloid and Sesquiterpenoid From the Leaves of <i>Cinnamomum bejolghota</i>

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, 4α,10α-dihydroxyaromadendrane-13-oic acid (2) along with seven known compounds, 4β,10α-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 (IC₅₀) values of 97.8 and 68.8 µM, respectively and moderate inhibitory activity on MCF7 cancer cell line with an IC₅₀ value of 49.7 µM.