Synthesis, Crystal Structure and Conformation of the Cyclic Dipeptide cyclo(-L-Seryl-L-seryl-)

Article abstract of DOI:10.1107/S0567740881003701

The synthesis, spectral data and X-ray structure determination of the cyclic dipeptide cyclo(-L-Ser-L-Ser-), C6H10N2O4, are reported.The compound was obtained by intramolecular aminolysis of two serine residues bridged via esteric bonds by a hydrocarbon chain.IR, CD and 1H NMR spectra are discussed in order to determine the salient features of the structure in solution.Crystals are orthorhombic, space group P2₁2₁2₁, with cell dimensions a=11.096(2), b=7.787(1), c=8.538(1) Angstroem; R=0.053 for 784 observed reflections.The diketopiperazine ring (DKP) is nearly planar.Intermolecular hydrogen bonds connect the DKP rings in spirals parallel to the <001> axis.