MGDA, GLDA, ASDA and EDTA belong to amino carboxylic acid chelating agents with similar structure.

MGDA:
Alanine, N,N-bis(carboxymethyl)-, trisodium salt;
Methylglycine N,N-diAcetic acid, trisodium salt;
GLDA:
L-Glutamic acid, N,N-bis(carboxymethyl)-, sodium salt (1:4);
Glutamic acid N,N-diAcetic acid tetrasodium salt;
ASDA:
Aspartic acid, N,N-bis(carboxymethyl)-, tetrasodium salt;
L-aspartic acid N, N-diAcetic acid tetrasodium salt;

EDTA:
Glycine, N,N’-1,2-ethanediylbis[N-(carboxymethyl)-;
Ethylene diamine tetraAcetic acid;

The important raw materials of MGDA, GLDA and ASDA are alanine, glutamic acid, aspartic acid respectively (amino acids), and the final products are easier to biodegrade.
Their synthesis process routes are also similar to EDTA too.