THE CRYSTAL AND MOLECULAR-STRUCTURE OF TERGURIDE MONOHYDRATE

The structure of terguride monohydrate (C20H28N4O . H2O) was solved by direct methods and refined anisotropically to R = 0.069 for 3040 unique observed reflections. The title compound crystallizes in space group C2 with lattice parameters a = 38.262(4), b = 7.834(3), c = 13.497(2) angstrom, beta = 101.69(2)-degrees, Z = 8. Two independent terguride molecules (denoted as A and B) were found in asymmetric unit, each includes tetracyclic ergoline ring system (one five-membered and three six-membered rings). The pyrrole moiety is nearly planar, the ergoline C ring has half boat conformation (in both molecules). Conformation of the ergoline D ring can be described as almost regular chair for A molecule, whereas it is considerably distorted for B molecule. The three-dimensional hydrogen bond network is built through water molecules only.