Spectroscopic study of molecular associations between riboflavin and some β-carboline derivatives

Hetero-association of aromatic molecules in aqueous solution

“…In order to understand the molecular mechanism of this effect, an investigation was conducted of the interaction of a series of structurally selected BCs and indoles with two typical representatives of the flavin family (FN), riboflavin and flavin-mononucleotide, [171][172][173][174][175]. The formation of 1:1 non-fluorescent molecular complexes was observed and the equilibrium constants and thermodynamical parameters of complexation were calculated.…”

“…There are some early investigations of the hetero-association of the riboflavin vitamins (RBF or FMN) with other aromatic compounds: the complexation of RBF/FMN with a series of betacarbolines, indoles [171][172][173][174][175], simple hydrocarbons [176][177][178][179][180] and some antibiotics [129,130]. The formation of 1:1 stacked complexes of aromatic molecules was reported, where an increase in stability and lowering of entropy was related to the increase in aromaticity of the drug chromophore in RBF-drug complexes for a series of betacarbolines and some other hydrocarbons [171].…”

Thermodynamic Study of Small Hydrophobic Ions at the Water–Lipid Interface

“…The first model considers a simple binding equilibrium between the free interacting molecule, P, the free phospholipid binding sites (unoccupied membrane site containing N phospholipids), S N , and the interacting molecule bound to lipid vesicles, P S N , expressed as (23,24) P + S N ← → P S N , [1] with a characteristic association constant, K A :…”

“…Significant low values for norharman and tryptophan have been demonstrated in mental retardation (4), whereas increased levels of norharman are detected in alcoholic syndrome (5), where norharman's action is connected with microsomal membranes containing cytochrome P450 enzymes. 1 To whom correspondence should be addressed.…”

“…The naturally occurring β-carbolines, such as norharman, exert numerous behavioral effects in animals and have antidepressant actions in humans (1). Parkinsonian-like symptoms via N-methylation of simple β-carbolines have been recently described (2).…”