Is planarity of pyridin-2-yl- and pyrazin-2-yl-formamide thiosemicarbazones related to their tuberculostatic activity? X-ray structures of two pyrazine-2-carboxamide-Nâ²-carbonothioyl-hydrazones
Keywords: Tuberculostatics; Intramolecular hydrogen bonds; Planar zwitterionic molecule; Five-bonds conjugation; Crystal structures;