Methods of treating ovarian cancer, endometrium cancer, cervical cancer, pancreatic cancer, bladder cancer, eve cancer, central nervous system cancer, thyroid cancer and lung cancer are disclosed. Specifically disclosed are methods of treating ovarian adenocarcinoma that has migrated into the abdominal cavity, a transitional cell carcinoma of the bladder, an epithelioid carcinoma in a pancreatic duct, an adenocarcinoma in a pancreatic duct, an adenocarcinoma in the cervical epithelium. The methods comprise administering to a patient a therapeutically effective amount of a compound of formula (Ia) ##STR00001## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, and R.sub.5 are described herein, wherein at least two of the five R.sub.1, R.sub.2, R.sub.3, R.sub.4, and R.sub.5 substituents are always hydrogen, at least one of the five substituents is always nitro, and at least one substituent positioned adjacent to a nitro is always iodo, and pharmaceutically acceptable salts thereof.