title: Maleimide-functionalized photochromic spirodihydroindolizines.
abstract: Two photochromic spirodihydroindolizine/betaine systems for tethering to peptides and proteins via a maleimide function have been prepared. The absorption spectra of the betaines are in the red region of the visible spectrum and in the near-IR spectral domain, which are suitable energies of light for future in vivo applications. The half-times of cyclization have been determined for both DHI/betaine systems. The findings are consistent with a thermal barrier of varying size between the transoid and cisoid conformers of the betaines.
authors.affiliation: Department of Anatomy & Physiology, Kansas State University, Coles 130, Manhattan, Kansas 66506, United States. tbs3@vet.k-state.edu
authors.forename: Tej B
authors.initials: TB
authors.lastname: Shrestha
authors.forename: Mausam
authors.initials: M
authors.lastname: Kalita
authors.forename: Megh Raj
authors.initials: MR
authors.lastname: Pokhrel
authors.forename: Yao
authors.initials: Y
authors.lastname: Liu
authors.forename: Deryl L
authors.initials: DL
authors.lastname: Troyer
authors.forename: Claudia
authors.initials: C
authors.lastname: Turro
authors.forename: Stefan H
authors.initials: SH
authors.lastname: Bossmann
authors.forename: Heinz
authors.initials: H
authors.lastname: Dürr
mesh_terms: D001622:Betaine / Q000737:chemistry*; D007212:Indolizines / Q000737:chemistry*; D008301:Maleimides / Q000737:chemistry*; D015394:Molecular Structure; D010777:Photochemistry; D019265:Spectroscopy, Near-Infrared; D013141:Spiro Compounds / Q000737:chemistry*
chemical_list: D007212:Indolizines; D008301:Maleimides; D013141:Spiro Compounds; C043592:maleimide; D001622:Betaine