GLYCYL-L-LEUCYL-L-TYROSINE DIHYDRATE 2-PROPANOL SOLVATE

The asymmetric unit (C17H25N3O5.C3H8O.2H(2)O) consists of two crystall ographically independent peptide molecules, A and B, with different co nformations, chi(2)(1) being trans and gauche(-) for the Leu residues in molecules A and B, respectively. The backbone conformation of both peptide molecules resembles that of the beta-pleated sheet arrangement found in proteins. Comparison with two other structures containing th e tripeptide Gly-L-Leu-L-Tyr reveals almost identical molecular confor mations, and in one instance also a common packing pattern.