Fluorescence studies on potential antitumoral heteroaryl and heteroannulated indoles in solution and in lipid membranes.
Fluorescence properties of three potential antitumoral compounds, a 3-(dibenzothien-4-yl)indole 1, a phenylbenzothienoindole 2 and a 3-(dibenzofur-4-yl)indole 3, were studied in solution and in lipid aggregates of dipalmitoyl phosphatidylcholine (DPPC), dioleoyl phosphatidylethanolamine (DOPE) and egg yolk phosphatidylcholine (Egg-PC). The 3-(dibenzofur-4-yl)indole 3 exhibits the higher fluorescence quantum yields in all solvents studied (0.32 <or= Phi(F) <or= 0.51). All the compounds present a solvent sensitive emission, with significant red shifts in alcohols. The results point to an ICT character of the excited state, more pronounced for compound 1. Fluorescence (steady-state) anisotropy measurements of the compounds incorporated in lipid aggregates of DPPC, DOPE and Egg-PC indicate that the three compounds are deeply located in the lipid bilayer, feeling the difference between the rigid gel phase and fluid phases.
Castanheira
Elisabete M S
EM
Centro de Física, Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal. ecoutinho@fisica.uminho.pt
Abreu
Ana S
AS
Carvalho
M Solange D
MS
Queiroz
Maria-João R P
MJ
Ferreira
Paula M T
PM
D000970:Antineoplastic Agents / Q000737:chemistry*; D002462:Cell Membrane / Q000737:chemistry*; D005453:Fluorescence; D005454:Fluorescence Polarization; D007211:Indoles / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D010743:Phospholipids / Q000737:chemistry*; D012996:Solutions; D013050:Spectrometry, Fluorescence
D000970:Antineoplastic Agents; D007211:Indoles; D010743:Phospholipids; D012996:Solutions