| abstract |
PCT No. PCT/US97/21474 Sec. 371 Date Aug. 16, 1999 Sec. 102(e) Date Aug. 16, 1999 PCT Filed Nov. 19, 1997 PCT Pub. No. WO98/21956 PCT Pub. Date May 28, 1998The invention provides a method of inhibiting cancer cell growth, and thereby of treating cancer comprising administering to a mammal afflicted with cancer an effective amount of the compound of formula (I), wherein the variables of R1, and R2 have the meanings defined in the specification. The present invention also provides novel compounds of formula (I) as well as novel pharmaceutical compositions and intermediates useful for preparing compounds of formula (I). The figure illustrates the structure and binding activity of compounds of the invention and some of the rifamycin analogs. - - <IMAGE> - Compounds R1 = - A1 -OH - A2 -OH - A3 -OH - A4 -OH - A5 -OH - A6 -OH - A7 -OH - - A8 <IMAGE> - Compounds R2 = - A1 <IMAGE> - - A2 <IMAGE> - - A3 <IMAGE> - - A4 GE> - - A7 <IMAGE> - - A8 -H - Compounds IC50 (1) IC50 (2) - A1 10 uM 1 uM - A2 10 uM 3 uM - A3 10 uM 3 uM - A4 50 uM 5 uM - A5 >500 uM >50 uM - A6 >500 uM >50 uM - A7 >200 uM >50 uM - A8 >500 M >50 uM - |