Regioselective diversification of a cardiac glycoside, lanatoside C, by organocatalysis
Acylation of lanatoside C in the presence of organocatalyst 5 gave the C(4)-O-acylate in up to 90% regioselectivity (catalyst-controlled regioselectivity). Various functionalized acyl groups can be introduced at the C(4)-OH by a mixed anhydride method in
Carboxylate Anions Accelerate Pyrrolidinopyridine (PPy)-Catalyzed Acylation: Catalytic Site-Selective Acylation of a Carbohydrate by in Situ Counteranion Exchange
Acylpyridinium ions have been known as catalytically active species in acylation reactions catalyzed by 4-dimethylaminopyridine and its analogues. Acylpyridinium carboxylates were found to be 800-1300 times more reactive than the corresponding acylpyridin