Bioassay-guided fractionation of the roots of Ardisia cornudentata Mez (Myrsinaceae) led to the isolation of three new compounds, 3-methoxy-2-methyl-5-pentylphenol (1), 3-methoxy-2-methyl-5-(1′-ketopentyl)phenol (2), and cornudoside (3), together with twenty-six known compounds. Their structures were elucidated by analysis of spectroscopic data. Thirteen of these isolates, 1, 2, 4-6, 9-15, and 21 showed antitubercular activities against Mycobacterium tuberculosis H37R<sub>V</sub> in vitro, with MIC values of 2.5-60 μg/mL. Two alkyl benzoquinones, ardisianone (7) and cornudentanone (8), were reported for their selective cytotoxic activity against the NCI-H460 cancer cell line (IC<sub>50</sub> values of 2.3, 2.5 μg/mL).
