Skip to content

Ricardo Reyes-Chilpa

Departamento de Productos Naturales, Instituto de Química, Universidad Nacional Autónoma de México, Ciudad de México, México.

4 papers in the library · 44 citations · publishing 2019-2023

Papers

Extraction and Conversion Studies of the Antiaddictive Alkaloids Coronaridine, Ibogamine, Voacangine, and Ibogaine from Two Mexican Tabernaemontana Species (Apocynaceae).

Chemistry & biodiversity July 1, 2019 Felix Krengel, Marco V Mijangos, Marisol Reyes-Lezama et al. 17 citations

Methanol effectively extracts the antiaddictive alkaloids coronaridine, ibogamine, voacangine, and ibogaine (the CIVI-complex) from the root barks of Mexican Tabernaemontana alba and Tabernaemontana arborea. A one-step demethoxycarbonylation process then converts coronaridine and voacangine directly into ibogamine and ibogaine, simplifying the mixture from four to two major compounds. This protocol improves qualitative and quantitative analysis and offers a viable method for bulk production of these therapeutically important substances from these promising plant sources.

Tabernaemontana arborea and ibogaine induce paroxysmal EEG activity in freely moving mice: Involvement of serotonin 5-HT1A receptors.

Neurotoxicology March 1, 2022 María Eva González-Trujano, Felix Krengel, Ricardo Reyes-Chilpa et al. 14 citations

A hydroalcoholic extract of Tabernaemontana arborea and its alkaloids ibogaine and voacangine altered brain electrical activity in mice. The extract at 56.2 and 100 mg/kg and ibogaine at 30 mg/kg increased delta and reduced alpha EEG band power, indicating central nervous system depression. Voacangine at 30 mg/kg flattened EEG patterns. None of the treatments modified seizures induced by pentylenetetrazole, but the extract at 100 mg/kg combined with the convulsant caused sudden death. Paroxysmal EEG activity from the extract and ibogaine was explored; a serotonin 5-HT1A receptor antagonist blocked the extract's but not ibogaine's paroxysmal activity, implicating serotonin neurotransmission in the extract's excitatory effects.

Quantitative Evaluation of a Mexican and a Ghanaian Tabernaemontana Species as Alternatives to Voacanga africana for the Production of Antiaddictive Ibogan Type Alkaloids.

Chemistry & biodiversity May 1, 2020 Felix Krengel, Jonathan Dickinson, Christopher Jenks et al. 7 citations

Gas chromatography-mass spectrometry (GC/MS) compared the alkaloid profiles of bark and leaf from one Mexican species (Tabernaemontana arborea) and one African species (T. crassa) with the primary commercial sources of semisynthetic ibogaine, Voacanga africana root and stem bark. The qualitative and quantitative similarities between T. arborea and V. africana barks support previous reports that T. arborea is a promising alternative source of voacangine and ibogaine. The results also suggest that T. crassa could be used to produce conopharyngine and ibogaline, two compounds with the same basic skeletal structure and possibly similar antiaddictive properties as ibogaine.

Potent Anti-amoebic Effects of Ibogaine, Voacangine and the Root Bark Alkaloid Fraction of Tabernaemontana arborea.

Planta medica February 1, 2023 Julio César Carrero, Violeta Curay-Herrera, Lysette Chacón-niño et al. 6 citations

Alkaloids from the root bark of Tabernaemontana arborea, particularly ibogaine and voacangine, show potent anti-amoebic activity against Entamoeba histolytica trophozoites in culture, with IC50 values of 4.5 and 8.1 µM at 24 hours, comparable to metronidazole (6.8 µM). However, the effect diminished after 48 and 72 hours, suggesting the alkaloids may be catabolized into less active derivatives by the parasites. In a hamster model of amoebic liver abscess, the alkaloids reduced the number of trophozoites in liver tissue but did not prevent abscess formation, indicating rapid inactivation in vivo. The findings suggest potential for these compounds as leads for new amoebiasis treatments, though further work is needed to address metabolic instability.