(untitled) - Jang,M.; Cai,E.N.; Udeani,G.O.; Slowing,K.V.; Thomas,C.F.; Beecher,C.W. W.; Fong,H.H. S.; Farnsworth,N.R.; Kinghorn,A.D.; Mehta,R.G.; Moon,R.C.; Pezzuto,J.M. (Science, 1997)