The solution-phase synthesis of a muramyl dipeptide(MDP) analogue of N~α-[4-chlorocinnamoyl-L-alanyl-D-isoglutaminyl]-L-lysine (MDA,2) is reported that possesses the features of easy feasibility,safety and low cost in large scale of synthesis. The solution-phase synthesis of a muramyl dipeptide (MDP) analogue of N ~ α- [4-chlorocinnamoyl-L-alanyl-D-isoglutaminyl] -L- lysine (MDA, 2) is reported that possesses the features of easy feasibility, safety and low cost in large scale of synthesis.