Penicillin V → N,N'-Dicyclohexylurea

Participants

Reaction Steps

In a 10 mL round-bottomed flask, 0.400 g (0.178 mmol) of the poly(PEG-Lys) having ethanolamide pendant functional groups of Example 6 was dissolved in 4 mL of methylene chloride. To this solution was added 0.094 g (0.267 mmol) of Penicillin V (Sigma) and 0.008 g (0.065 mmol) of dimethylaminopyridine (Aldrich). The reaction mixture was cooled in an ice water bath and then 0.048 g (0.232 mmol) of DCC was added. After a few hours at 0° C., the reaction vessel was moved to a cold room maintained at 420 C. and allowed to stir for almost six days. A precipitate of dicyclohexyl urea formed and was removed by filtration. The drug conjugate was precipitated with cold ether. About 0.250 g of crude product was obtained which was purified by reprecipitation twice from isopropanol. TLC in methanol showed absence of free drug.

Provenance & Evidence