Changes in Acid-Base Equilibria of Harmine and Harmane Inclusion Complexes with Cyclodextrins

The Impact of Dihydrogen Phosphate Anions on the Excited-State Proton Transfer of Harmane. Effect of β-Cyclodextrin on These Photoreactions

“…Inclusion complexes of some β-carboline alkaloids with β-CD have been already described in the literature. − In these studies, the β-CDs exerted a significant influence on the proton transfer of some β-carboline derivatives. In the presence of β-CD, access of the protons to the pyridinic nitrogen was not possible due to the lower diffusion rate of protons inside these cavities with a lower polarity than water, decreasing the basicity of these organic bases.…”

“…On the other hand, it is known − some β-carboline derivatives form inclusion complexes with the β-cyclodextrin (β-CD). The formation of inclusion complexes between HAR and β-CD reduces the number of species in aqueous solution, and this could help us understand the formation mechanisms of all of these species.…”

Additive effect of harmane and muscimol for memory consolidation impairment in inhibitory avoidance task

“…Functional characterization of harmane and related compounds has shown a complex pharmacology following exogenous injection (Rommelspacher et al, 1994). It has been suggested that harmane acts as an endogenous ligands at imidazoline and benzodiazepine binding site of the GABA A receptors (Rommelspacher et al, 1980, Husbands et al, 2001, Musgrave et al, 2003, with the effect of weakening neuronal excitation through inhibition of voltage-gated calcium channel currents (Martin et al, 1997). Up to now, the effective concentration of harmane around the neurons is not well-known and effective levels range from 10 −10 to 10 −4 M [1-3].…”

“…Harmane has a fully unsaturated pyridine ring, but no group substitution in C7, which explain its lack of activity in memory enhancement (Moura et al, 2006). As regards harmane inhibited voltage-gated calcium channel currents and so reduced neuronal excitation (Martin et al, 1997, Splettstoesser et al, 2005, it could decrease memory consolidation.…”