Erythromycin → Flurithromycin

Participants

Reaction Steps

Erythromycin A (5 g, 6.813 mmole) was dissolved in glacial acetic acid (20 mL) at room temperature and stirred for 2 hours. The pH of the mixture was adjusted to 4.3 with 6N sodium hydroxide (approx. 12.5 mL) while the temperature was maintained below 20° C. 1-Chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (2.4 g, 6.813 mmole) was added and stirring continued for an additional 3 hours at 22° C. The reaction was worked up in the same manner as Example 1 to afford 4.5 g of crude flurithromycin. This material was recrystallized as described in Example 1 to yield 2.6 g (51% yield) of flurithromycin.

Provenance & Evidence