Conformational Behavior of N1-(Diphenylphosphoryl)acetyl-N4-phenyl-thiosemicarbazide in Various Crystal Environments

Three crystal modifications of phenyl-substituted diphenylphosphoryl thiosemicarbazide (compound (1) and two its solvates with dimethyl sulfoxide (2, 3)) have been obtained and analyzed by the X-ray diffraction (XRD) method. The independent molecules of compounds in crystals 1 and 2 are characterized by the identical (“rolled”) conformation of acyclic framework, stabilized by the intramolecular hydrogen bond N–H⋅⋅⋅O, and their crystals exhibit the formation of an identical chain supramolecular motif, oriented along the axis corresponding to the smallest unit-cell parameter. In crystal 3, the independent molecules are in two different conformations: one is stabilized by an intramolecular hydrogen bond, and the other (“linear”) is due to the molecular adjustment during the formation of a point supramolecular associate with a hydrophilic nucleus and a hydrophobic shell.