Diisopropylethylamine → 4-{[2-N-(Benzyloxycarbonyl)-guanin-9-yl]acetyl}-1-(2-nitro-benzenesulfonyl)-piperazin-2-one

Participants

Reaction Steps

To a solution of [2-N-(benzyloxycarbonyl)-guanin-9-yl]-acetic acid (1.48 g, 4.5 mmol), 1-(2-nitro-benzenesulfonyl)-piperazin-2-one HCl salt (1.45 g, 4.5 mmol), and PyBOP (2.81 g, 5.4 mmol) in DMF (13 mL) was added N,N-diisopropylethylamine (1.96 mL, 13 mmol) at room temperature. After stirring for additional 40 min, the reaction mixture was diluted with water (80 mL) to precipitate solid. The solid was filtered off, washed with ethyl alcohol and triturated with acetonitrile and THF to give pure product (1.56 g, 58%). 1H NMR (DMSO-d6) δ 11.47 (s, 1H), 11.38 (s, 1H), 8.40˜7.96 (m, 4H), 7.82 (s, 0.6H), 7.78 (s, 0.4H), 7.45˜7.35 (m, 5H), 5.25 (s, 2H), 5.13 (s, 1.2H), 5.04 (s, 0.8H), 4.51 (s, 0.8H), 4.26 (s, 1.2H), 4.10˜4.02 (m, 2.4H), 3.93˜3.83 (m, 1.6H).

Provenance & Evidence