Discovery of new polymorphs of the tuberculosis drug isoniazid†
Abstract
Two new metastable polymorphs of the tuberculosis drug isoniazid, considered monomorphic for sixty years, were discovered using melt crystallization and nanoscale confinement. The two new forms are readily distinguished from the known form by optical microscopy, Raman spectroscopy and X-ray powder diffraction. A single crystal structure was obtained for one of the new polymorphs.