5667-11-8Relevant articles and documents
Bivalent β-carbolines as potential multitarget anti-alzheimer agents
Rook, Yvonne,Schmidtke, Kai-Uwe,Gaube, Friedemann,Schepmann, Dirk,Wünsch, Bernhard,Heilmann, J?rg,Lehmann, Jochen,Winckler, Thomas
, p. 3611 - 3617 (2010)
Alzheimer's disease (AD) is a prevalent neurodegenerative disorder with multifactorial causes that requires multitargeted treatment. Inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) improve cholinergic signaling in the central nervous system and thus AChE inhibitors are well established in the therapy of AD to improve memory disturbances and other cognitive symptoms. On the other hand, AD patients benefit from reduction of pathologic glutamate-induced, Ca2+-mediated excitotoxicity by the N-methyl-d-aspartate receptor (NR) antagonist memantine. New drugs that simultaneously affect both cholinergic transmission and glutamate-induced excitotoxicity may further improve AD treatment. While connecting β-carboline units by alkylene spacers in two different series of compounds and subsequent evaluation of their AChE/BChE-inhibitory potential, we found that several of these bivalent β-carbolines were potent NR blockers. The most promising compound was a N9-homobivalent β-carboline with a nonylene spacer, which displayed IC50 values of 0.5 nM for AChE, 5.7 nM for BChE, and 1.4 μM for NR, respectively.
Photophysical and Photochemical Properties of Naturally Occurring normelinonine F and Melinonine F Alkaloids and Structurally Related N(2)- and/or N(9)-methyl-β-carboline Derivatives
Rasse-Suriani, Federico A. O.,García-Einschlag, Fernando S.,Rafti, Matías,Schmidt De León, Tobías,David Gara, Pedro M.,Erra-Balsells, Rosa,Cabrerizo, Franco M.
, p. 36 - 51 (2017/10/07)
In the present work, we have synthesized and fully characterized the photophysical and photochemical properties of a selected group of N-methyl-β-carboline derivatives (9-methyl-β-carbolines and iodine salts of 2-methyl- and 2,9-dimethyl-β-carbolinium) in aqueous solutions, in the pH range 4.0–14.5. Moreover, despite the quite extensive studies reported in the literature regarding the overall photophysical behavior of N-unsubstituted βCs, this work constitutes the first full and unambiguous characterization of anionic species of N-unsubstituted βCs (norharmane, harmane and harmine), present in aqueous solution under highly alkaline conditions (pH > 13.0). Acid dissociation constants (Ka), thermal stabilities, room temperature UV–visible absorption and fluorescence emission and excitation spectra, fluorescence quantum yields (ФF) and fluorescence lifetimes (τF), as well as quantum yields of singlet oxygen production (ФΔ) have been measured for all the studied compounds. Furthermore, for the first time to our knowledge, chemometric techniques (MCR-ALS and PARAFAC) were applied on these systems, providing relevant information about the equilibria and species involved. The impact of all the foregoing observations on the biological role, as well as the potential biotechnological applications of these compounds, is discussed.