Half-lives for the partial reactions involved in hydrolysis of thymidine 5´-bis[3-acetyloxy-2-cyano-2-(2-phenylethylcarbamoyl)propyl]phosphate (1) to 5´-TMP at pH 7.5 and 37 °C (I = 0.1 mol L-1 with NaCl). For the reactions, see Scheme 4. [HLE] = 26 units mL-1. The corresponding half-lives reported previously [29] for thymidine 5´-bis[3-acetyloxymethoxy-2,2-bis(ethoxycarbonyl)propyl]phosphate (2) and thymidine 5´-bis[3-acetyloxy-2,2-bis(ethoxycarbonyl)propyl]phosphate (3) are included for reference.