Planta Med 2015; 81 - PQ28
DOI: 10.1055/s-0035-1556362

A novel pimarane diterpene and cytotoxic angucyclines from a marine-derived actinomycete in Vietnam

MW Mullowney 1, EÓ hAinmhire 1, 2, U Tanouye 1, B Wan 3, S Cho 3, SG Franzblau 1, 3, JE Burdette 1, 2, PV Cuong 4, BT Murphy 1, 2
  • 1Dept of Med Chem & Pharmacognosy, COP, UIC, Chicago, IL, USA
  • 2Center for Pharmaceutical Biotechnology, COP, UIC, Chicago, IL Illinois, USA
  • 3Institute for Tuberculosis Research, COP, UIC, Chicago, IL, USA
  • 4Institute of Marine Biochemistry, Vietnam Academy of Science and Technology, Hanoi, Vietnam

A screening of our actinomycete fraction library against a cisplatin-resistant ovarian cancer cell line (OVCAR5) led to the isolation of catbapimarenone (1), lagumycin B (2), dehydrorabelomycin (3), phananthroviridone (4), and WS-5995 A (5). These compounds were produced by a Micromonospora sp. isolated from sediment in the East Sea of Vietnam. Compounds 2 – 4 were cytotoxic with LC50 values ranging from 0.34 µg/mL to 9.12 µg/mL, while 5 exhibited selective cytotoxicity toward the Kuramochi cell line and 1 was inactive. Compound 1 is a novel Δ8,9-pimarane diterpene, representing one of approximately twenty actinomycete-produced diterpenes reported to date while 2 has yet to receive formal characterization in the peer-reviewed literature. The structure elucidation of 1 and 2 was performed by combined NMR, MS, and CD spectroscopic analysis. The isolation and cytotoxicity of 1 – 5, as well as the structure elucidation of 1 will be presented.