Planta Med 2012; 78 - PI242
DOI: 10.1055/s-0032-1320929

Growth inhibition of human colon carcinoma cells by diterpenes and tetralones of Zygogynum calothyrsum

KP Devkota 1, D Covell 2, T Ransom 1, JB McMahon 1, JA Beutler 1
  • 1Molecular Targets Laboratory, Center for Cancer Research, Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, Maryland 21702, United States
  • 2Screening Technologies Branch, Developmental Therapeutics Program, National Cancer Institute, Frederick, Maryland 21702, United States

Bioassay guided phytochemical investigation of Zygogynum calothyrsum using human colon carcinoma cells COLO205 and KM12 led to the isolation of three new drimane-type diterpenes, 11-hydroxy-11,12-epoxydrimane (1), 5,11-dihydroxy-11,12-epoxydrimane (2) and 11,12-dimethoxy-11,12-epoxydrimane (3), the known 1β-p-coumaroyloxypolygodial (4) together with two new tetralones, 3'-dehydroxyisozygolone (5) and calothyrlone A (9), three known tetralones, isozygolone A (6), zygolone A (7) and 4'-O-methylzygolone A (8) and a known cinnamolide (10). Compounds 1, 7 and 8 demonstrated higher cytotoxicity against COLO205 (GI50=17.8, 16.7 and 11.4 µM, respectively) and KM12 (GI50=13.5, 14.2 and 17.2 µM, respectively) than other compounds.