L-Alanine → Boc-Asn-Ala-OBzl

Participants

Reaction Steps

1.5 g (4.24 mmoles) of p-nitrophenyl ester of BOC-Asparagine are added to a solution cooled to 0° of 1.7 g (4.84 mmoles) of p-toluene sulfonate of the benzyl ester of alanine and of 0.53 ml (4.84 mmoles) of N-methylmorpholine, in 15 ml of dimethylformamide. After 24 hours at ambiant temperature, the product is purified as described above. In suspension in ether, 1.33 g (79%) of the product is obtained after filtration, having a melting point and a rotatory power (in dimethyl formamide) respectively of m.p. 138°-141°; αD25 = 17.5° (c = 1.02 DMF).

Provenance & Evidence