The first participant on this study will receive the dose that has been found to be well-tolerated in an ongoing study involving participants with primary brain tumors. After this participant has completed 1 study cycle, the next participant will be given a higher dose of RTA 744. Each new participant will receive a higher dose level until a patient has an intolerable side effect. When this happens, at least 2 more participants will be given the dose level that causes the intolerable side effect. If there are no further intolerable side effects to RTA 744, the next group of 3 participants will be given the next higher dose of RTA 744. Each time, the dose of RTA 744 will not be increased until the effects of the previous dose level have been studied. Doses will increase with each group of patients until the highest tolerable dose is found.