3-AP and Gemcitabine in Treating Patients With Recurrent, Unresectable, or Metastatic Pancreatic Cancer

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed pancreatic adenocarcinoma * Recurrent, unresectable, or metastatic disease * At least 1 unidimensionally measurable lesion * At least 20 mm by conventional techniques OR at least 10 mm by spiral CT scan * Prior radiation field must not have encompassed the only site of measurable disease * No known brain metastases PATIENT CHARACTERISTICS: Age * 18 and over Performance status * ECOG 0-2 OR * Karnofsky 60-100% Life expectancy * More than 12 weeks Hematopoietic * WBC ≥ 3,000/mm\^3 * Absolute neutrophil count ≥ 1,500/mm\^3 * Platelet count ≥ 100,000/mm\^3 * No G6PD deficiency Hepatic * Bilirubin ≤ 1.5 times normal * AST and ALT ≤ 2.5 times upper limit of normal Renal * Creatinine ≤ 1.5 times normal OR * Creatinine clearance ≥ 60 mL/min Cardiovascular * No unstable angina pectoris * No cardiac arrhythmia * No symptomatic congestive heart failure Pulmonary * No severe pulmonary disease * No dyspnea at rest * No dependence on supplemental oxygen use Other * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception during and for 3 months after study treatment * No prior allergic reaction attributed to compounds of similar chemical or biological composition to study drugs * No ongoing or active infection * No psychiatric illness or social situation that would preclude study compliance * No other concurrent uncontrolled illness that would preclude study participation PRIOR CONCURRENT THERAPY: Biologic therapy * Not specified Chemotherapy * No prior chemotherapy except fluorouracil given as adjuvant therapy OR as a radiosensitizer during radiotherapy * More than 4 weeks since prior adjuvant fluorouracil therapy Endocrine therapy * Not specified Radiotherapy * See Disease Characteristics * See Chemotherapy * More than 4 weeks since prior radiotherapy and recovered Surgery * Not specified Other * No other concurrent investigational agents * No other concurrent anticancer therapy * No concurrent combination antiretroviral therapy for HIV-positive patients