(R)-sec-butylamine → 3-[2-((R)-sec-Butylamino)-3,4-dioxo-cyclobut-1-enylamino]-6-chloro-2-hydroxy-N-methoxy-N-methyl-benzenesulfonamide

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 6-chloro-3-(2-ethoxy-3,4-dioxo-cyclobut-1-enylamino)-2-hydroxy-N-methoxy-N-methyl-benzenesulfonamide (Intermediate A) (1 g, 2.56 mmol) in THF (20 ml) was added (R)-(−)-2-aminobutane (0.52 ml, 5.12 mmol). The reaction mixture was heated at 50° C. for 7 hours. The reaction mixture was concentrated in vacuo and dissolved in EtOAc. The EtOAc solution was washed with 1M HCl(aq) and brine. The EtOAc solution was dried (MgSO4) and concentrated in vacuo. The residue was crystallized from toluene to give a solid; [M+H]+ 418.2. 1H NMR (DMSO) 0.9 (3H, t, CH3), 1.2 (3H, d, CH3), 1.5 (2H, m), 3.0 (3H, s, CH3), 3.6 (3H, s, CH3), 4.0 (1H, m), 7.2 (1H, d), 8.1 (1H, d), 8.3 (1H, d), 9.4 (1H, s), 10.1 (1H, s).

Provenance & Evidence