Capecitabine (5'-Deoxy-5-fluoro-N-[(pentyloxy)carbonyl]cytidine, Ro-9-1978, Xeloda)

Capecitabine is a pre-prodrug of 5-fluorouracil (5-FU). After oral uptake, capecitabine is first metabolized to 5'-deoxy-5-fluorocytidine (5'-DFCR), which happens mainly in the liver by carboxyl-esterase. The metabolite is converted to 5'-deoxy-5-fluoro-uridine (5'-DFUR) by cytidine deaminase in liver and tumor tissue. Then 5'-DFUR is converted to 5-FU intracellularly by thymidine phosphorylase, which is often expressed in tumor tissue. Solubility: Soluble in DMSO at 100mg/ml, soluble in ethanol at 12.5mg/ml with slight warming, soluble in water at 2mg/ml with slight warming, buffers, serum, or other additives may increase or decrease the aqueous solubility. Storage and Stability: May be stored at RT for short-term only. Long-term storage is recommended at -20°C. For maximum recovery of product, centrifuge the original vial prior to removing the cap.