Koo, Ki Dong; Kim, Min Jung; Kim, Sungsub; Kim, Kyoung-Hee; Hong, Sang Yong; Hur, Gwong-Cheung; Yim, Hyeon Joo; Kim, Geun Tae; Han, Hee Oon; Kwon, O Hwan; Kwon, Tae Sik; Koh, Jong Sung; Lee, Chang-Seok Bioorganic and Medicinal Chemistry Letters, 2007 , vol. 17, # 15 p. 4167 - 4172