(d) By inclusion of the 2-amino nitrogen atom in a cyclic structure. Examples of substituted cathinones include, but are not limited to, methylone (3,4-methylenedioxymethcathinone), MDPV (3,4-methylenedioxypyrovalerone), mephedrone (4-methylmethcathinone), 4-methoxymethcathinone, 4-fluoromethcathinone, 3-fluoromethcathinone, Pentedrone (2-(methylamino)-1-phenyl-1-pentanone), pentylone (1-(1,3-benzodioxol-5-yl)-2-(methylamino)-1-pentanone), 2-(1-pyrrolidinyl)-1-(4-methylphenyl)-1-propanone, alpha-PVP (1-phenyl-2-(1-pyrrodinyl)-1-pentanone), cathinone (2-amino-1-phenyl-1-propanone), and methcathinone (2-(methylamino)-propiophenone).
In 2009, India's Chandrayaan-1 satellite, NASA's Cassini spacecraft and the Deep Impact probe have each detected the presence of water by evidence of hydroxyl fragments on the Moon. As reported by Richard Kerr, "A spectrometer [the Moon Mineralogy Mapper, . "M3"] detected an infrared absorption at a wavelength of micrometers that only water or hydroxyl—a hydrogen and an oxygen bound together—could have created."  NASA also reported in 2009 that the LCROSS probe revealed an ultraviolet emission spectrum consistent with hydroxyl presence.  The Venus Express orbiter sent back Venus science data from April 2006 until December 2014. Results from Venus Express include the detection of hydroxyl in the atmosphere.