A convenient and functional-group-tolerant organocatalytic asymmetric 1,4-addition of azlactones and dehydroalanine is disclosed. The reaction is used for the first synthesis of chiral α,γ-diamino diacid derivatives with nonadjacent stereogenic centers in moderate to high yields, with excellent diastereo- and enantioselectivities, under the catalysis of a chiral thiourea catalyst. In addition, the reaction could be conducted in gram-scale, and the products of the reaction could be readily converted to various α,γ-diamino diacid derivatives, α,γ-diamino dialcohols, and modified peptides with nonproteinogenic amino acid residues.