[Crystalline structure of L-leucyl-L-leucyl-L-tyrosine chlorhydrate]

C21H34N3O5+.Cl-, Mr = 444.0, orthorhombic, P2(1)2(1)2(1), a = 26.074 (5), b = 17.591 (4), c = 5.224 (2) A, V = 2396.1 (10) A3, Z = 4, Cu K alpha, lambda = 1.5418 A, mu = 1.71 mm-1, F(000) = 952, D chi = 1.231 Mg m-3, room temperature, final R = 0.080 and wR = 0.070 for 2439 reflections [(sin theta)/lambda greater than 0.03 A-1]. The peptide groups are planar; torsion angles (-101 and -88 degrees) indicate a roughly helical structure. The peptide bonds have a trans conformation. The crystal structure is stabilized by a network of hydrogen bonds.