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

Abstract

In the present work, we have synthesized and fully characterized the photophysical and photochemical properties of a selected group of N-methyl-b-carboline derivatives (9-methylb-carbolines and iodine salts of 2-methyl-and 2,9-dimethyl-bcarbolinium) 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 Nunsubstituted bCs, this work constitutes the first full and unambiguous characterization of anionic species of N-unsubstituted bCs (norharmane, harmane and harmine), present in aqueous solution under highly alkaline conditions (pH > 13.0). Acid dissociation constants (K a ), thermal stabilities, room temperature UV-visible absorption and fluorescence emission and excitation spectra, fluorescence quantum yields (Ф F ) and fluorescence lifetimes (s F ), as well as quantum yields of singlet oxygen production (Ф D ) 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.

Simultaneous Production of Psilocybin and a Cocktail of β‐Carboline Monoamine Oxidase Inhibitors in “Magic” Mushrooms

“…[10] Upon exposure to UV light, b-carbolines fluoresce. [11] Therefore, we repeated the analysis, this time using an acidic aqueous mushroom extract and an HPLC instrumenti nterfaced to af luorescenced etector,e xcitation was at l = 340 nm, emissionw as recorded at l = 410 nm. The signals were detected again, and authentic 4 and 5 standards showedi dentical retention times and masses ( Figure 1B).…”

β-Carboline derivatives as novel antivirals for herpes simplex virus

“…Norharmane, harmane, harmine, harmaline, 6-methoxy-harmane and Acyclovir (Sigma-Aldrich Co.) were of the highest purity available (>98%). Non-commercial derivative synthesis was described previously (purity >98%) [16][17][18][19]. Stock solutions of βCs were prepared in pH 2 sterile ultrapure water [11,20] and diluted (10%, vol/vol) to working concentrations in DMEM.…”

N-Methyl-β-carboline alkaloids: structure-dependent photosensitizing properties and localization in subcellular domains

“…β-Carbolines (βCs) are a set of endogenous alkaloids present in a vast range of living species. [1][2][3][4][5][6][7][8] The βC skeleton construction occurs through the catalysed Pictet-Spengler reaction. [9][10][11] In particular, N-methyl-β-carboline alkaloids, including normelinonine F (1b) and melinonine F (2b), were isolated from different mammals' body tissues and fluids such as brain, cerebrospinal and plasma.…”

“…[9][10][11] In particular, N-methyl-β-carboline alkaloids, including normelinonine F (1b) and melinonine F (2b), were isolated from different mammals' body tissues and fluids such as brain, cerebrospinal and plasma. [1][2][3][4][5][6][7] A broad spectrum of biological, biomedical and pharmacological activities has been reported for these alkaloids:…”