“…cis-3,6-Bis[(acetyloxy)methyl]piperazine-2,5-dione (25) was prepared by using methodology similar to the methodology used for the prepartion of the (chloroacetyl)oxy analogue.17 A mixture of cis-24 (1.0 g, 5.75 mmol), AcCl (1.8 mL, 25.1 mmol), and glacial HOAc (2.5 mL) was stirred at room temperature for 5 h. An additional 2.5 mL of HOAc was added at the end of 1.5 h. The mixture was diluted with Me2CO, filtered, and recrystallized from MeOH, yielding trans-3,6-Bis[(acetyloxy)methyl]piperazine-2,5-dione (25) was prepared by using methodology similar to that employed for the preparation of the (chloroacetyl)oxy analogue.17 A mixture of trans-24 (1.0 g, 5.75 mmol), AcCl (1.8 mL, 25.1 mmol), HOAc (5 mL), and 10 drops of H2S04 was stirred for 2 days at room temperature with occasional warming. The mixture was diluted with H20, filtered, and recrystallized from MeOH, yielding 0.53 g (35.8%) of white crystals: mp 237-238 °C; IR (KBr) 1740 (ester), 1680 (amide) cm'1; NMR (Me2SO-d6, 90 MHz) 2.02 (s, 6 H, COCH3), 4.22 (s, br, 6 H, OCH2CH), 8.37 (s, 2 H, CONH).…”