Formaldehyde → 5-(5-methyl-1-((2-(4-methylpiperazin-1-yl)pyridin-4-yl) methyl)-1H-1,2,4-triazol-3-yl)-3-(4-(trifluoromethoxy)phenyl)-1,2,4-oxadiazole

Participants

Reaction Steps

The mixture of 4-(4-((5-methyl-3-(3-(4-(trifluoromethoxy)phenyl)-1,2,4-oxadiazol-5-yl)-1H-1,2,4-triazol-1-yl)methyl)pyridin-2-yl)piperazin-1-ium trifluoroacetate (100 mg, 0.2 mmol), formaldehyde (0.5 mL, 6.0 mmol, 38% in H2O) and paraformaldehyde (100 mg, 3.3 mmol) in EtOH (1 mL) was stirred at RT, then treated with NaBH3CN (63 mg, 1.0 mmol) in one portion. The mixture was stirred at RT for 3 h, and then concentrated under reduced pressure to give the crude product, which was purified by pre-HPLC (Mobile phase: A=10 mM NH4HCO3/H2O, B=MeCN; Gradient: B=60%-95% in 18 min; Column: XBridge C18, 5 um, 30 mm×150 mm) to afford 5-(5-methyl-1-((2-(4-methylpiperazin-1-yl)pyridin-4-yl) methyl)-1H-1,2,4-triazol-3-yl)-3-(4-(trifluoromethoxy)phenyl)-1,2,4-oxadiazole as a white solid (45 mg, 45%). MS (ES+) C23H23F3N8O2 requires: 500. found: 501 [M+H]+; 1H NMR (500 MHz, DMSO-d6) δ 8.22 (d, J=8.3 Hz, 2H), 8.08 (d, J=5.3 Hz, 1H), 7.60 (d, J=8.2 Hz, 2H), 6.77 (s, 1H), 6.42 (d, J=5.3 Hz, 1H), 5.50 (s, 2H), 3.50-3.48 (m, 4H), 2.58 (s, 3H), 2.41-2.32 (m, 4H), 2.20 (s, 3H).

Provenance & Evidence