Pyrazoloacridine Followed by Radiation Therapy in Treating Adults With Newly Diagnosed Supratentorial Glioblastoma Multiforme

DISEASE CHARACTERISTICS: Histologically proven, newly diagnosed, supratentorial, grade IV astrocytoma (glioblastoma multiforme) Incompletely resected disease Must have measurable and contrast enhancing tumor on the postoperative MRI/CT scan PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 60-100% Life expectancy: Not specified Hematopoietic: Absolute neutrophil count at least 1,500/mm^3 Platelet count at least 100,000/mm^3 Hepatic: Bilirubin no greater than 1.5 mg/dL Transaminases no greater than 4 times upper limit of normal Renal: Creatinine no greater than 1.7 mg/dL Other: No other serious concurrent infection or medical illness that would preclude study therapy No other active malignancy within the past 5 years except curatively treated carcinoma in situ of the cervix or basal cell skin cancer No psychosis requiring ongoing therapy with antipsychotic medication Mini mental score at least 15 Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception PRIOR CONCURRENT THERAPY: Biologic therapy: No prior immunotherapy or biologic agents (including immunotoxins, immunoconjugates, antisense compounds, peptide receptor antagonists, interferons, interleukins, tumor infiltrating lymphocytes, lymphokine activated killer cells, or gene therapy) for glioblastoma multiforme No concurrent prophylactic growth factors (e.g., filgrastim [G-CSF] or sargramostim [GM-CSF]) Chemotherapy: No prior chemotherapy for glioblastoma multiforme Endocrine therapy: No prior hormonal therapy for glioblastoma multiforme Prior glucocorticoids allowed Concurrent corticosteroids allowed if on stable dose (no increase within the past 5 days) Radiotherapy: No prior radiotherapy for glioblastoma multiforme Surgery: See Disease Characteristics Recovered from immediate postoperative period Other: Greater than 10 days since prior anticonvulsants that induce hepatic metabolic enzymes (e.g., phenytoin, carbamazepine, phenobarbital, primidone, or felbamate) No other concurrent investigational agents