反应详情

This compound was prepared from the product of 6b (2.75 g; 6.5 mmol) and 33% HBr in acetic acid (5 mL) as described in Example 1c. The crude product was purified by flash chromatography on a 40×55 mm silica gel 60 column eluted with 10% methanol in acetonitrile (400 mL) collecting 20×10 ml fractions. After evaporation of fractions 4-15 and vacuum-drying for 48 h at 40° C. and 0.01 mm Hg 1.60 g (71%) product was obtained (orange foam, mp 77-80° C.).

1. customThe crude product was purified by flash chromatography on a 40×55 mm silica gel 60 column
2. washeluted with 10% methanol in acetonitrile (400 mL)
3. customcollecting 20×10 ml fractions
4. customAfter evaporation of fractions 4-15
5. customvacuum-drying for 48 h at 40° C.