Two polymorphs of phenanthro[4,5-abc]phenazine-18-crown-6: Preparation, X-ray diffraction and DFT studies

Heterocyclic Nanographenes and Other Polycyclic Heteroaromatic Compounds: Synthetic Routes, Properties, and Applications

Two-dimensionally extended, polycyclic heteroaromatic molecules (heterocyclic nanographenes) are a highly versatile class of organic materials, applicable as functional chromophores and organic semiconductors. In this Review, we discuss the rich chemistry of large heteroaromatics, focusing on their synthesis, electronic properties, and applications in materials science. This Review summarizes the historical development and current state of the art in this rapidly expanding field of research, which has become one of the key exploration areas of modern heterocyclic chemistry.

Concomitant polymorphs of methoxyflavone (5-methyl-7-methoxyflavone)

A novel metastable polymorph and an unstable amorphous phase of methoxyflavone were discovered after a decade since the first report of the X-ray crystal structure of this bioactive compound.