Linear Oligopeptides .254. Molecular and Crystal-structure of N-alpha-benzyloxycarbonyl-l-proline Amide

The molecular and crystal structure of N(alpha)-benzyloxycarbonyl-L-proline amide (Z-L-Pro-NH2) (1) has been determined by X-ray diffraction. The compound possesses the following parameters: orthorhombic, space group P2(1)2(1)2(1), (No. 19), a = 18.113(2) angstrom, b = 13.809(2) angstrom, c = 5.010(2) angstrom, and Z = 4. The crystal structure was solved by direct methods. The least-squares refinement led to R and R(w) values of 0.045 and 0.046, respectively, for 1082 reflections with I greater-than-or-equal-to 3-sigma(I). This Pro derivative adopts the collagen-type conformation. The Z-Pro tertiary urethane bond is found in the cis disposition.