title: Solvent Effects on Molecular Aggregation in 4-(5-Heptyl-1,3,4-thiadiazol-2-yl)benzene-1,3-diol and 4-(5-Methyl-1,3,4-thiadiazol-2-yl)benzene-1,3-diol.
abstract: The article presents the results of spectroscopic studies of 4-(5-methyl-1,3,4-thiadiazol-2-yl)benzene-1,3-diol (C1) and 4-(5-heptyl-1,3,4-thiadiazol-2-yl)benzene-1,3-diol (C7) in organic solvent solutions. Depending on the concentration of the compound used, three bands were observed in the fluorescence emission spectra of the compounds in DMSO solutions. A single band was observed in methanol, propan-2-ol, or ethanol. The significantly shortened fluorescence lifetimes and the different shapes of circular dichroism (CD) spectra clearly indicate association of the fluorescence effects with the aggregation processes in the analyzed compounds. The differences in the course of the CD spectra also imply an effect of the substituent group structure on the molecule aggregation interactions. Therefore, it has been postulated that the occurrence of the different spectral forms induced by changes in the compound concentration may be related to the aggregation effects of C1 and C7 molecules, which are also induced by differences in the alkyl substituent structure.
authors.affiliation: Department of Biophysics, University of Life Sciences in Lublin , Akademicka 13, 20-950 Lublin, Poland.
authors.forename: Arkadiusz
authors.initials: A
authors.lastname: Matwijczuk
authors.affiliation: Department of Cell Biology, Institute of Biology, Maria Curie-Skłodowska University , 20-033 Lublin, Poland.
authors.forename: Dariusz
authors.initials: D
authors.lastname: Kluczyk
authors.affiliation: Department of Physical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology of the Jagiellonian University , Gronostajowa 7, 30-387 Krakow, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Górecki
authors.affiliation: Department of Chemistry, University of Life Sciences in Lublin , 20-950 Lublin, Poland.|Institute of Industrial Organic Chemistry , Annopol 6, 03-236 Warsaw, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Niewiadomy
authors.affiliation: Department of Cell Biology, Institute of Biology, Maria Curie-Skłodowska University , 20-033 Lublin, Poland.
authors.forename: Mariusz
authors.initials: M
authors.lastname: Gagoś