5-Methoxycanthinone is a β-carboline first isolated from the Australian Rutaceae Pentaceras Australis Hook by Price and co-workers at the CSIRO, Australia in 1952. 5-Methoxycanthinone is a modest inhibitor of a panel of the human tumor cell lines: epiderimoid carcinoma of the nasopharynx (KB), lung carcinoma (A-549), ileocecal carcinoma (HCT-8), renal cancer (CAKI-1), breast cancer (MCF-7), melanoma (SK-MEL-2) with ED50 of 2.9, 3.1, 2.5, 4.4, 5.0 and 17 µg/mL.
