Ammonia → Carnosine

Participants

Reaction Conditions

Reaction Steps

0.3 g of rhodium/activated carbon (5% Rh) was added to a solution of 1.90 g (7.8 mmol) of (S)-2-(cyanoacetyl-amino)-3-(1H-imidazol-4-yl)propionic acid, sodium salt (prepared according to Example 1) in 50 ml of ethanol/conc. ammonia solution (V:V=4:1). The mixture was hydrogenated at 110° C. and 45 bar for 1 h. This was followed by filtering off the catalyst and adjusting the filtrate to a pH of 8.2 with formic acid. After concentrating the solution under reduced pressure, the residue was suspended in 200 ml of ethanol and heated at 60° C. for 30 min. The product was filtered off, washed successively with ethanol, ethyl acetate and diethyl ether and finally dried.

Provenance & Evidence