摘要:1-(β-D-Arabinofuranosyl)-2-thiocytosine (araSC), a 2-substituted derivative of cytarabine (araC), has been investigated for its cytotoxicity, enzymatic stability, plasma concentration-time profile in mice, and cytokinetics.This derivative showed strong cytotoxicity in several mammalian cell lines, although activity (IC50s) was weaker than araC. Greater stability to mouse cytidine deaminase was observed; the half-line in the presence of the enzyme was about 4-times longer than that of araC. The plasma concentration-time profile in mice in vivo showed prolonged retention of araSC when compared with araC. Cytokinetic study using flow cytometry indicated a non-S-phase specific effect of this compound.