OUTLINE: This is a dose escalation study. The first 3 patients receive intoplicine IV by continuous infusion for 5 days. Treatment is repeated every 28 days in the absence of disease progression or unacceptable toxicity. Subsequent cohorts of 3-6 patients receive escalating doses of intoplicine, first by increasing the number of days that the drug is infused to 10, 15, and 21, then by increasing the dosage and keeping the infusion time constant at 21 days. The intolerable dose level is defined as the lowest dose at which at least 2 of 3 or 6 patients experience dose limiting toxicity during course 1 or 2.