Abstract
2-Benzoylpyridine piperidinyl- and hexamethyleneiminylthiosemicarbazones, HBzpip and HBzhexim, respectively, crystallize in a hydrogen bonded Z isomeric conformation with respect to the C7–N2 bond. The intramolecular hydrogen bond is between N3–H…N1, but the S atom is E to the azomethine nitrogen, N2, for HBzpip and Z for HBzhexim. HBzpip is the second ZE isomer known, but the first that does not have a formal hydrogen bond to N2.