title: Spectrophotometric characteristics of new pyridylindolizine derivatives solutions.
abstract: Three new pyridylindolizine derivatives, 1, 2, 3-tricarbometoxi-7-(4-pyridyl)-pyrrolo[1, 2-a]pyridine (I), 1,2-dicarboethoxy-3-(4-bromobenzoyl)-7-(4-pyridyl)-pyrrolo[1,2-a]pyridine (II) and its isomer 1,2-dicarboethoxy-3- (4-bromobenzoyl) -5- (2-pyridyl) -pyrrolo[1, 2-a]pyridine (III) have been investigated in different solutions by UV-VIS absorption, steady-state, and time-resolved fluorescence methods. The effects of the substituent and solvent on the spectroscopic properties have been demonstrated. The fluorescence decay data could be fitted to a single-exponential function. The lifetime values are higher in protic polar than in aprotic apolar solvents for compound I. In the case of compounds II and III the fluorescence intensities and lifetimes are very low, with the exception of III in aprotic solvents. The absorption and fluorescence properties of the compounds showed a solvent dependence.
authors.affiliation: Institute of Physical Chemistry, Romanian Academy, Splaiul Independentei 202, 006021 Bucharest, Romania. mvasilescu@chimfiz.icf.ro
authors.forename: Marilena
authors.initials: M
authors.lastname: Vasilescu
authors.forename: Rodica
authors.initials: R
authors.lastname: Bandula
authors.forename: F
authors.initials: F
authors.lastname: Dumitrascu
authors.forename: H
authors.initials: H
authors.lastname: Lemmetyinen
mesh_terms: D007212:Indolizines / Q000737:chemistry*; D015394:Molecular Structure; D012996:Solutions; D012997:Solvents; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet
chemical_list: D007212:Indolizines; D012996:Solutions; D012997:Solvents