1,5-Diisocyanonaphthalene
1,5-Diisocyanonaphthalene is an aromatic diisocyanide in which two –N≡C groups occupy the 1- and 5-positions of the naphthalene ring. The compound is also named 1,5-naphthalenediyldiisocyanide and has the molecular formula and relative molar mass 178.19 g/mol. It has been studied as a photophysical probe and as a lead compound for antifungal research.
Structure and properties
Isocyanides feature the –N≡C functional group, bonded to the aromatic ring through nitrogen. DIN's two isocyanide substituents make it a rigid, weakly polar π-system. Photophysically, DIN shows limited solvatochromism compared with mono-formamido/mono-isocyano analogues, but it forms notable π-complexes with aromatic solvents that modulate emission, enabling discrimination among aromatics by fluorescence.
Synthesis
1,5-Diisocyanonaphthalene can be obtained by converting 1,5-diaminonaphthalene to the corresponding N,-diformamide, followed by dehydration. Reaction conditions and solvent choice influence outcome for this system.
Applications
Fluorescence/analytical: DIN's emission responds to specific π–π interactions in aromatic solvents, suggesting use in distinguishing aromatic hydrocarbons optically; related hydrolysis-derived ICNF is a strongly solvatochromic dye.
In standardized CLSI broth microdilution tests against three Aspergillus fumigatus strains, 1,5-diisocyanonaphthalene showed the lowest MIC values among the tested isocyano-naphthalene derivatives, namely 0.6 μg/mL for all strains. Practical use may be limited by poor aqueous solubility; a related dimethylamino analogue progressed to in-vivo evaluation in a murine aspergillosis model.