title: Reactions of CF3-enones with arenes under superelectrophilic activation: a pathway to trans-1,3-diaryl-1-CF3-indanes, new cannabinoid receptor ligands.
abstract: 4-Aryl-1,1,1-trifluorobut-3-en-2-ones ArCH[double bond, length as m-dash]CHCOCF3 (CF3-enones) react with arenes in excess of Brønsted superacids (TfOH, FSO3H) to give, stereoselectively, trans-1,3-diaryl-1-trifluoromethyl indanes in 35-85% yields. The reaction intermediates, the O-protonated ArCH[double bond, length as m-dash]CHC(OH(+))CF3 and the O,C-diprotonated ArHC(+)CH2C(OH(+))CF3 species, have been studied by means of (1)H, (13)C, (19)F NMR, and DFT calculations. Both types of the cations may participate in the reaction, depending on their electrophilicity and electron-donating properties of the arenes. The formation of CF3-indanes is a result of cascade reaction of protonated CF3-enones to form chemo-, regio- and stereoselectively three new C-C bonds. The obtained trans-1,3-diaryl-1-trifluoromethyl indanes were investigated as potential ligands for cannabinoid receptors CB1 and CB2 types. The most potent compound showed sub-micromolar affinity for both receptor subtypes with a 6-fold selectivity toward the CB2 receptor with no appreciable cytotoxicity toward SHSY5Y cells.
authors.affiliation: Institute of Chemistry, Saint-Petersburg State University, 198504 Saint-Petersburg, Petrodvorets, Universitetsky pr., 26, Russia. m.krasavin@spbu.ru.
authors.forename: Roman O
authors.initials: RO
authors.lastname: Iakovenko
authors.forename: Anna N
authors.initials: AN
authors.lastname: Kazakova
authors.forename: Vasiliy M
authors.initials: VM
authors.lastname: Muzalevskiy
authors.forename: Alexander Yu
authors.initials: AY
authors.lastname: Ivanov
authors.forename: Irina A
authors.initials: IA
authors.lastname: Boyarskaya
authors.forename: Andrea
authors.initials: A
authors.lastname: Chicca
authors.forename: Vanessa
authors.initials: V
authors.lastname: Petrucci
authors.forename: Jürg
authors.initials: J
authors.lastname: Gertsch
authors.forename: Mikhail
authors.initials: M
authors.lastname: Krasavin
authors.forename: Galina L
authors.initials: GL
authors.lastname: Starova
authors.forename: Andrey A
authors.initials: AA
authors.lastname: Zolotarev
authors.forename: Margarita S
authors.initials: MS
authors.lastname: Avdontceva
authors.forename: Valentine G
authors.initials: VG
authors.lastname: Nenajdenko
authors.forename: Aleksander V
authors.initials: AV
authors.lastname: Vasilyev
mesh_terms: D000143:Acids / Q000737:chemistry; D001554:Benzene / Q000737:chemistry; D066241:Carbon-13 Magnetic Resonance Spectroscopy; D018360:Crystallography, X-Ray; D004583:Electrons; D063388:Endocannabinoids / Q000737:chemistry; D007189:Indans / Q000138:chemical synthesis* / Q000737:chemistry*; D008024:Ligands; D047028:Macrocyclic Compounds / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D066244:Proton Magnetic Resonance Spectroscopy; D011522:Protons; D011789:Quantum Theory; D043882:Receptors, Cannabinoid / Q000378:metabolism*
chemical_list: D000143:Acids; D063388:Endocannabinoids; D007189:Indans; D008024:Ligands; D047028:Macrocyclic Compounds; D011522:Protons; D043882:Receptors, Cannabinoid; D001554:Benzene