title: Photoswitching azo compounds in vivo with red light.
abstract: The photoisomerization of azobenzenes provides a general means for the photocontrol of molecular structure and function. For applications in vivo, however, the wavelength of irradiation required for trans-to-cis isomerization of azobenzenes is critical since UV and most visible wavelengths are strongly scattered by cells and tissues. We report here that azobenzene compounds in which all four positions ortho to the azo group are substituted with bulky electron-rich substituents can be effectively isomerized with red light (630-660 nm), a wavelength range that is orders of magnitude more penetrating through tissue than other parts of the visible spectrum. When the ortho substituent is chloro, the compounds also exhibit stability to reduction by glutathione, enabling their use in intracellular environments in vivo.
authors.affiliation: Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada.
authors.forename: Subhas
authors.initials: S
authors.lastname: Samanta
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Beharry
authors.forename: Oleg
authors.initials: O
authors.lastname: Sadovski
authors.forename: Theresa M
authors.initials: TM
authors.lastname: McCormick
authors.forename: Amirhossein
authors.initials: A
authors.lastname: Babalhavaeji
authors.forename: Vince
authors.initials: V
authors.lastname: Tropepe
authors.forename: G Andrew
authors.initials: GA
authors.lastname: Woolley
mesh_terms: D001391:Azo Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D008027:Light; D008958:Models, Molecular; D015394:Molecular Structure; D055668:Photochemical Processes
chemical_list: D001391:Azo Compounds; C009850:azobenzene