Reaction Steps
Reagent 2-(1-methoxy-2-(3-nitrophenyl)ethylidene)malononitrile (1.2 g; 4.7 mmol) was combined with tert-butylhydrazine-HCl (0.57 g; 5.2 mmol; Sigma-Aldrich), 1.4 mL triethylamine in 50 mL EtOH for at 2 hours at 80° C. The reaction was concentrated in vacuo, resuspended in brine and extracted with chloroform. The organic layer was dried over MgSO4. Following, the organic suspension was filtered, concentrated in vacuo, and purified on silica gel in 1% MeOH:CHCl3 to yield 3-(3-nitrobenzyl)-1-tert-butyl-5-amino-1H-pyrazole-4-carbonitrile (ESI-MS m/z [M−CH3]+ found 285.5, calculated 285.14; 1H NMR (400 MHz, DMSO): δ8.11 (s, 1H), 8.08-8.12 (m, 1H), 7.69 (d, J=8 Hz, 1H), 7.59-7.64 (m, 1H), 3.96 (s, 2H), 3.34 (br, 2H), 1.52 (s, 9H)). This product was combined with formamide as per Cmpd 1 to yield 3-(3-nitrobenzyl)-1-tert-butyl-1H-pyrazolo[3,4-d]pyrimidin-4-amine (ESI-MS m/z [M+H]+ found 327.4, calculated 327.15; 1H NMR (400 MHz, DMSO): δ 8.22 (s, 1H), 8.14 (s, 1H), 8.07 (d, J=8 Hz, 1H), 7.67 (d, J=8 Hz, 1H), 7.59 (d, J=8 Hz, 1H), 7.22 (br, 2H), 4.52 (s, 2H), 1.70 (s, 9H)). Reduction of this material was completed as per Cmpd 1 to yield 3-(3-aminobenzyl)-1-tert-butyl-1H-pyrazolo[3,4-d]pyrimidin-4-amine (ESI-MS m/z [M+H]+ found 297.13, calculated 297.17). The reduced precursor was coupled to 3-(trifluoromethyl)phenyl isocyanate and purified as described for Cmpd 1 to yield Cmpd 4 1-(3-((1-tert-butyl-4-amino-1H-pyrazolo[3,4-d]pyrimidin-3-yl)methyl)phenyl)-3-(3-(trifluoromethyl)phenyl)urea (ESI-MS m/z [M+H]+ found 484.5, calculated 484.2; 1H NMR (400 MHz, DMSO): δ 9.25 (s, 1H), 8.96 (s, 1H), 8.32 (s, 1H), 8.06 (s, 1H), 7.46-7.55 (m, 2H), 7.40 (s, 1H), 7.29 (d, J=8 Hz, 2H), 7.20 (t, J=8 Hz, 1H), 6.89 (d, J=8 Hz, 1H), 4.39 (s, 2H), 1.73 (s, 9H). 13C NMR (400 MHz, DMSO): δ 29.25, 33.40, 60.74, 99.58, 116.43 (d), 116.95, 118.86, 122.13, 122.64, 124.69 (q), 129.29, 129.98 (q), 130.32, 139.60, 140.06, 141.16, 143.31, 149.70, 152.69, 152.92, 154.81, 159.12 (q)).
