(S)-3-(hydroxymethyl)-6a,7,8,9-tetrahydropyrido[3,2-e]pyrrolo[1,2-a]pyrazin-6(5H)-one (100 mg, 0.456 mmol), N-methyl-4-(piperazin-1-yl)benzenesulfonamide (116 mg, 0.456 mmol), (cyanomethyl)trimethylphosphonium iodide (166 mg, 0.684 mmol) and N,N-diisopropylethylamine (0.398 ml, 2.281 mmol) were suspended in propiononitrile (Volume: 1.370 ml) and heated in a closed vial at 90-120° C. for 4 h. The reaction mixture became a dark brown solution. It was cooled to room temperature, concentrated in vacuo, dissolved in DMSO (2 mL) and purified using HPLC (basic, 10-95% ACN in water). The fractions were concentrated in vacuo and the resulting solid was recrystallized from water-methanol (2:1, 6 mL) and dried in vacuum to afford (S)—N-methyl-4-(4-((6-oxo-5,6,6a,7,8,9-hexahydropyrido[3,2-e]pyrrolo[1,2-a]pyrazin-3-yl)methyl)piperazin-1-yl)benzenesulfonamide (110 mg, 0.241 mmol, 52.8% yield) as a tan solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.88-2.04 (m, 3 H) 2.15-2.27 (m, 1 H) 2.38 (d, J=4.80 Hz, 3 H) 2.51 (d, J=4.29 Hz, 4 H) 3.32 (br. s., 4 H) 3.38-3.49 (m, 3 H) 3.57-3.69 (m, 1 H) 3.97-4.07 (m, 1 H) 7.02 (d, J=1.52 Hz, 1 H) 7.07 (d, J=9.09 Hz, 2 H) 7.15 (q, J=4.72 Hz, 1 H) 7.59 (d, J=8.84 Hz, 2 H) 7.66 (d, J=1.77 Hz, 1 H) 10.48 (s, 1 H). [M+H] calc'd for C24H29ClN6O2, 457; found, 457.
