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Names | |
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IUPAC name 12-Methoxyibogamine-18-carboxylic acid, methyl ester | |
Systematic IUPAC name Methyl 17-ethyl-7-methoxy-3,13-diazapentacyclo[13.3.1.02,10.04,9.013,18] nonadeca-2(10),4,6,8-tetraene-1-carboxylate [1] | |
Other names Methyl 12-methoxyibogamine-18-carboxylate | |
Identifiers | |
3D model (JSmol) | |
ChEBI | |
ChEMBL | |
ChemSpider | |
ECHA InfoCard | 100.214.137 |
MeSH | Voacangine |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
C22H28N2O3 | |
Molar mass | 368.477 g·mol−1 |
Melting point | 136 to 137 °C (277 to 279 °F; 409 to 410 K) |
log P | 3.748 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Voacangine (12-methoxyibogamine-18-carboxylic acid methyl ester) is an alkaloid found predominantly in the root bark of the Voacanga africana tree, as well as in other plants such as Tabernanthe iboga , Tabernaemontana africana , Trachelospermum jasminoides , Tabernaemontana divaricata and Ervatamia yunnanensis . [2] [3] [4] [5] It is an iboga alkaloid which commonly serves as a precursor for the semi-synthesis of ibogaine. [6] It has been demonstrated in animals to have similar anti-addictive properties to ibogaine itself. [7] It also potentiates the effects of barbiturates. [8] Under UV-A and UV-B light its crystals fluoresce blue-green, and it is soluble in ethanol.
Voacangine exhibits AChE inhibitory activity. [9] [10] Docking simulation reveals that it has inhibitory effect on VEGF2 kinase [11] and reduces angiogenesis. [12] [13] Like ibogaine, its a potent HERG blocker in vitro. [14] It also acts as antagonist to TRPM8 and TRPV1 receptor, but agonist of TRPA1. [15] [16]
The absolute bioavailability of voacangine is around 11–13%. [14]
High doses of voacangine produce convulsions and asphyxia. [17]
The late-stage biosynthesis of (-)-voacangine in Tabernanthe iboga , a (-)-ibogamine-type alkaloid, has been elucidated via homology-guided transcriptome mining. [18] Suspected RNA transcripts involved in (-)-voacangine biosynthesis were identified via sequence homology to previously described enzymes comprising the (+)-catharanthine biosynthesis, [19] a (+)-ibogamine-type alkaloid from the taxonomically related plant Catharanthus roseus .
Ibogamine-type alkaloids are biosynthesized from the late stage intermediate stemmadenine acetate, a strictosidine-derived biosynthetic intermediate for a wide number of plant natural products. The biosynthesis of stemmadenine acetate has been characterized in C. roseus [19] but remains uncharacterized in T. iboga.
Conversion of stemmadenine acetate to (-)-voacangine in T. iboga involves five enzymes. First, stemmadenine acetate (1) is converted to precondylocarpine acetate (2) by one of three T. iboga precondylocarpine acetate synthases (TiPAS1/2/3), a flavin-dependent oxidase. Next, 2 is reduced to the enamine (3), dihydroprecondylocarpine acetate, by one of two NADPH-dependent T. iboga dihydroprecondylocarpine acetate synthase (TiDPAS1/2).
Up to this point, the biosynthetic path towards the (-)-ibogamine alkaloids and (+)-ibogamine alkaloids is identical. Stereochemical divergence occurs during the cyclization step, whereby T. iboga coronaridine synthase (TiCorS), a catharanthine synthase (CS) homologue, catalyzes a stereoselective formal Diels-Alder reaction on dehydrosecodine (4) to form coronaridine iminium (5). A proposed mechanism for dehydrosecodine formation from 3 involves iminium-formation/deacetylation, enamine-formation, and subsequent isomerization. Reduction of 5 to (-)-coronaridine (6) is proposed to be catalyzed by TiDPAS, although it is unclear if the reduction is actually enzymatic due to a lack of a reaction trial with only NADPH. [Note 1] After formation of 6, the substrate is then 10-hydroxylated by ibogamine 10-hydroxylase (I10H), a CYP450 enzyme, and subsequently 10-O-methylated by noribogaine-10-O-methyltransferase (N10OMT), a SAM dependent enzyme, [20] to form (-)-voacangine (7).
Apocynaceae is a family of flowering plants that includes trees, shrubs, herbs, stem succulents, and vines, commonly known as the dogbane family, because some taxa were used as dog poison. Members of the family are native to the European, Asian, African, Australian, and American tropics or subtropics, with some temperate members. The former family Asclepiadaceae is considered a subfamily of Apocynaceae and contains 348 genera. A list of Apocynaceae genera may be found here.
Tabernanthe iboga (iboga) is an evergreen rainforest shrub native to Central Africa. A member of the Apocynaceae family indigenous to Gabon, the Democratic Republic of Congo, and the Republic of Congo, it is cultivated across Central Africa for its medicinal and other effects.
Ibogaine is a psychoactive indole alkaloid obtained either by extraction from plants in the family Apocynaceae such as Tabernanthe iboga, Voacanga africana, and Tabernaemontana undulata or by semi-synthesis from the precursor compound voacangine, another plant alkaloid. The total synthesis of ibogaine was described in 1956. Structural elucidation by X-ray crystallography was completed in 1960.
Indole alkaloids are a class of alkaloids containing a structural moiety of indole; many indole alkaloids also include isoprene groups and are thus called terpene indole or secologanin tryptamine alkaloids. Containing more than 4100 known different compounds, it is one of the largest classes of alkaloids. Many of them possess significant physiological activity and some of them are used in medicine. The amino acid tryptophan is the biochemical precursor of indole alkaloids.
Voacanga africana is a small tree native to tropical Africa belonging to the family Apocynaceae that grows to 6 m (20 ft) in height and bears leaves that are up to 30 cm (12 in) in length. The yellow or white flowers are succeeded by paired, follicular, dehiscent fruit with a mottled green exocarp and a pulpy, yellow mesocarp surrounding the seeds. The plant contains alkaloids acting as CNS depressants and hypotensives.
Strictosidine synthase (EC 4.3.3.2) is an enzyme in alkaloid biosynthesis that catalyses the condensation of tryptamine with secologanin to form strictosidine in a formal Pictet–Spengler reaction:
Noribogaine, or 12-hydroxyibogamine, is the principal psychoactive metabolite of the oneirogen ibogaine. It is thought to be involved in the antiaddictive effects of ibogaine-containing plant extracts, such as Tabernanthe iboga.
Coronaridine, also known as 18-carbomethoxyibogamine, is an alkaloid found in Tabernanthe iboga and related species, including Tabernaemontana divaricata for which it was named.
Ibogamine is an anti-convulsant, anti-addictive, CNS stimulant alkaloid found in Tabernanthe iboga and Crepe Jasmine. Basic research related to how addiction affects the brain has used this chemical.
Tabernanthine is an alkaloid found in Tabernanthe iboga.
(−)-18-Methylaminocoronaridine (18-MAC) is a second generation synthetic derivative of ibogaine developed by the research team led by the pharmacologist Stanley D. Glick from the Albany Medical College and the chemist Martin E. Kuehne from the University of Vermont.
Voacamine, also known under the older names voacanginine and vocamine, is a naturally occurring dimeric indole alkaloid of the secologanin type, found in a number of plants, including Voacanga africana and Tabernaemontana divaricata. It is approved for use as an antimalarial drug in several African countries. Voacamine exhibits cannabinoid CB1 receptor antagonistic activity.
Stemmadenine is a terpene indole alkaloid. Stemmadenine is believed to be formed from preakuammicine by a carbon-carbon bond cleavage. Cleavage of a second carbon-carbon bond is thought to form dehydrosecodine. The enzymes forming stemmadenine and using it as a substrate remain unknown to date. It is thought to be intermediate compound in many different biosynthetic pathways such as in Aspidosperma species. Many alkaloids are proposed to be produced through intermediate stemmadenine. Some of them are:
Iboga-type alkaloids are a set of monoterpene indole alkaloids comprising naturally occurring compounds found in Tabernanthe and Tabernaemontana, as well as synthetic structural analogs. Naturally occurring iboga-type alkaloids include ibogamine, ibogaine, tabernanthine, and other substituted ibogamines. Many iboga-type alkaloids display biological activities such as cardiac toxicity and psychoactive effects, and some have been studied as potential treatments for drug addiction.
Ibogaline is an alkaloid found in Tabernanthe iboga along with the related chemical compounds ibogaine, ibogamine, and other minor alkaloids. It is a relatively smaller component of Tabernanthe iboga root bark total alkaloids (TA) content. It is also present in Tabernaemontana species such as Tabernaemontana australis which shares similar ibogan-biosynthetic pathways. The percentage of ibogaline in T. iboga root bark is up to 15% TA with ibogaine constituting 80% of the alkaloids and ibogamine up to 5%.
Tabernaemontanine is a naturally occurring monoterpene indole alkaloid found in several species in the genus Tabernaemontana including Tabernaemontana divaricata.
Dregamine is a naturally occurring monoterpene indole alkaloid found in several species in the genus Tabernaemontana including Ervatamia hirta and Tabernaemontana divaricata.
Vobasine is a naturally occurring monoterpene indole alkaloid found in several species in the genus Tabernaemontana including Tabernaemontana divaricata.
Voacristine is a indole alkaloid occurring in Voacanga and Tabernaemontana genus. It is also an iboga type alkaloid.
Conopharyngine is the major alkaloid present in the leaves and stem-bark of Tabernaemontana pachysiphon and Conopharyngia durissima. It is closely related voacangine and coronaridine. Conopharyngine pseudoindoxyl, a derivative of it, is also found in the same plant Tabernaemontana pachysiphon.