A novel preparation of L-citrulline and L-homocitrulline
L-citrulline was synthesized from L-ornithine monohydrochloride, which was treated with copper salt under alkaline conditions to protect α-NH 2, followed by formylation of δ-NH2 with carbamide, and the removal of copper ion via the combination with sulfides or organic acids to release L-citrulline in satisfactory yield. L-homocitrulline was prepared from L-lysine monohydrochloride with the same method. This new method has the advantages of being environmentally friendly and suitable for industrial production.