Ammonia methanol → 8-amino-1-[3-(aminosulfonyl)phenyl]-1H-benzo[g]indazole-3-carboxamide
Reaction equation
[NH2:1][S:2]([C:5]1[CH:6]=[C:7]([N:11]2[C:19]3[C:18]4[CH:20]=[C:21]([N+:24]([O-])=O)[CH:22]=[CH:23][C:17]=4[CH2:16][CH2:15][C:14]=3[C:13]([C:27]([O:29]CC)=O)=[N:12]2)[CH:8]=[CH:9][CH:10]=1)(=[O:4])=[O:3].[NH3:32].CO>>[NH2:24][C:21]1[CH:22]=[CH:23][C:17]2=[CH:16][CH:15]=[C:14]3[C:19]([N:11]([C:7]4[CH:8]=[CH:9][CH:10]=[C:5]([S:2]([NH2:1])(=[O:3])=[O:4])[CH:6]=4)[N:12]=[C:13]3[C:27]([NH2:32])=[O:29])=[C:18]2[CH:20]=1Participants
3
Procedure
A sealed solution of ethyl 1-[3-(aminosulfonyl)phenyl]-8-nitro-4,5-dihydro-1H-benzo[g]indazole-3-carboxylat from step 1 (2.20 g, 4.98 mmol) in excess NH3/MeOH was heated at 110° C. for 10 h. The mixture was then concentrated to 10 mL, cooled to RT and the solid product collected by filtration. The solid was dissolved in HOAc, exposed to H2 (5 psi) at RT in the presence of Pd—C (5%) for 2 h. The mixture was filtered through celite pad, concentrated, taken into MeOH, filtered again through celite. The clear solution was concentrated, recrystallized in EtOH to give a grey solid (450 mg). Its structure was confirmed by 1H NMR and MS (382, M+1). C18H15N5O3S.H2O.(Et2O)0.2, Calc.: C: 54.51, H: 4.62, N: 16.91; Found, C: 54.79, H: 4.06, N: 16.72.