Toluene → Cantharimide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of cantharidin (50 mg, 0.26 mmol), 2-amino-6-carboxybenzothiazole (294 mg, 1.27 mmol), and a mixture of dried toluene and dried triethylamine (4 mL; 2:1, v/v) may be sealed in a tube and heated for 3 hours at 180° C. The reaction mixture may be concentrated, followed by flash chromatography (dichloromethane:methanol, 10:1) that may give the product CAN039 (51.9 mg, 55%) of formula (3) as a white solid with the following characterization: mp=180-181° C.; Rf=0.27 (hexane:acetone, 2:1); 1H NMR (CD3OD, 500 MHz): δ 1.34 (6H, s), 1.72-1.74 (2H, m), 1.97-2.00 (2H, m), 4.69-4.70 (2H, m), 8.08 (1H, d, J=8.5 Hz), 8.18 (1H, dd, J=8.5 Hz and 1.5 Hz), 8.70-8.71 (1H, m); 13C NMR (CDCl3): δ 12.1, 23.7, 54.6, 85.0, 85.1, 122.5, 123.9, 127.9, 128.3, 132.7, 151.9, 155.3, 168.0, 178.7; MS (EI) m/z (%): 372 (M+); HRMS calcd. for C18H16N2O5S [M]+ found 358.0776.

Herkunft & Nachweise