Gleostine TM (lomustine) (CCNU) is one of the nitrosoureas used in the treatment of certain neoplastic diseases. It is 1-(2-chloro-ethyl)-3-cyclohexyl-1-nitrosourea. It is a yellow powder with the empirical formula of C 9 H 16 ClN 3 O 2. It is relatively un-ionized at a physiological pH.