ozonation of the adamantane: Oxidation of the alcohol gives adamantanone. Others Adamantane interacts with benzene in the presence of Lewis acids, resulting in a Friedel–Crafts reaction. Aryl-substituted adamantane derivatives can be easily obtained starting from 1-hydroxyadamantane. In particular, the reaction with anisole proceeds under normal conditions and does not require a catalyst. Nitration of adamantane is a difficult reaction characterized by moderate yields. A nitrogen-substituted drug amantadine can be prepared by reacting adamantane with bromine or nitric acid to give the bromide or nitroester at the 1-position. Reaction of either compound with acetonitrile affords the acetamide, which is hydrolyzed to give 1-adamantylamine: Uses Adamantane itself enjoys few applications since it is merely an unfunctionalized hydrocarbon. It is used in some dry etching masks and polymer formulations. In solid-state NMR spectroscopy, adamantane is a common standard for chemical shift referencing. In dye lasers, adamantane may be used to extend the life of the gain medium; it cannot be photoionized under atmosphere because its absorption bands lie in the vacuum-ultraviolet region of the spectrum. Photoionization energies have been determined for adamantane as well as for several bigger diamondoids. In medicine All medical applications known so far involve not pure adamantane, but its derivatives. The first adamantane derivative used as a drug was amantadine – first (1967) as an antiviral drug against various strains of influenza and then to treat Parkinson's disease. Other drugs among adamantane derivatives include adapalene, adapromine, bromantane, carmantadine, chlodantane, dopamantine, memantine, rimantadine, saxagliptin, tromantadine, and vildagliptin. Polymers of adamantane have been patented as antiviral agents against HIV. Influenza virus strains have developed drug resistance to amantadine and rimantadine, which are not effective against prevalent strains as of 2016. In designer drugs Adamantane was recently identified as a key structural subunit in several synthetic cannabinoid designer drugs, namely AB-001 and SDB-001. Spacecraft propellant Adamantane is an attractive candidate for propellant in Hall-effect thrusters because it ionizes easily, can be stored in solid form rather than a heavy pressure tank, and is relatively nontoxic. Potential technological applications Some alkyl derivatives of adamantane have been used as a working fluid in hydraulic systems. Adamantane-based polymers might find application for coatings of touchscreens, and there are prospects for using adamantane and its homologues in nanotechnology. For example, the soft cage-like structure of adamantane solid allow incorporation of guest molecules, which can be released inside the human body upon breaking the matrix. Adamantane could