Acetogenin

Acetogenins are a class of polyketide natural products found in plants of the family Annonaceae. They are characterized by linear 32- or 34-carbon chains containing oxygenated functional groups including hydroxyls, ketones, epoxides, tetrahydrofurans and tetrahydropyrans. They are often terminated with a lactone or butenolide.^[1] Over 400 members of this family of compounds have been isolated from 51 different species of plants.^[2] Many acetogenins are characterized by neurotoxicity.^[3]

Chemical structure of annonacin

Not to be confused with Acetogen.

Examples include:

• Annonacin
• Annonins
• Bullatacin
• Uvaricin

Structure

Acetogenin core unit (mono-THF)

Acetogenin terminal lactone ring core unit (unsaturated)

Structurally, acetogenins are a series of C-35/C-37 compounds usually characterized by a long aliphatic chain bearing a terminal methyl-substituted α,β-unsaturated γ-lactone ring, as well as one to three tetrahydrofuran (THF) rings.^[4] These THF rings are located along the hydrocarbon chain, along with a number of oxygenated moieties (hydroxyls, acetoxyls, ketones, epoxides) and/or double bonds.^[4]

Examples of R-groups for selected acetogenins ^[4]

Compound	R1	R2	R3	R4	R5
4-deoxyannoreticuin	OH	OH	H	H	H
Annonacin	OH	OH	H	OH	H
Annopentocin A	OH	H	H	OH	H
Dispalin	OAc	OH	H	OH	H
Donnaienin C	OH	OH	H	OAc	OH
Goniotetracin	OH	OH	H	OH	H
Muricoreacin	OH	H	H	OH	H
Tonkinin A	OH	OH	O	H	H
Uvaribonone	OH	OAc	O	H	H

Research

Acetogenins have been investigated for their biological properties, but are a concern due to neurotoxicity.^{[5][6][7][8][9]} Purified acetogenins and crude extracts of the common North American pawpaw (Asimina triloba) or the soursop (Annona muricata) remain under laboratory studies.^[10]

Mechanism of action

Acetogenins inhibit NADH dehydrogenase, a key enzyme in energy metabolism.^[11]

References

1. Li, N.; Shi, Z.; Tang, Y.; Chen, J.; Li, X. (2008). "Recent Progress on the Total Synthesis of Acetogenins from Annonaceae" (PDF). Beilstein Journal of Organic Chemistry. 4 (48): 1–62. doi:10.3762/bjoc.4.48. PMC 2633664. PMID 19190742.
2. Bermejo, A.; Figadère, B.; Zafra-Polo, M.-C.; Barrachina, I.; Estornell, E.; Cortes, D. (2005). "Acetogenins from Annonaceae: Recent Progress in Isolation, Synthesis and Mechanisms of Action". Natural Product Reports. 22 (2): 269–303. doi:10.1039/B500186M. PMID 15806200. Erratum: "Back Matter". Natural Product Reports. 22 (3): 426. 2005. doi:10.1039/B503508M.
3. Liaw, Chih-Chuang; Liou, Jing-Ru; Wu, Tung-Ying; Chang, Fang-Rong; Wu, Yang-Chang (2016). Acetogenins from Annonaceae. Progress in the Chemistry of Organic Natural Products. Vol. 101. pp. 113–230. doi:10.1007/978-3-319-22692-7_2. ISBN 978-3-319-22691-0. PMID 26659109.
4. Alali, Feras Q; Liu, Xiao-Xi; McLaughlin, Jerry L (1999). "Annonaceous Acetogenins: Recent Progress". Journal of Natural Products. 62 (3): 504–40. doi:10.1021/np980406d. PMID 10096871.
5. Ana V. Coria-Téllez; Efigenia Montalvo-Gónzalez; Elhadi M. Yahia; Eva N. Obledo-Vázquez (2018). "Annona muricata: A comprehensive review on its traditional medicinal uses, phytochemicals, pharmacological activities, mechanisms of action and toxicity". Arabian Journal of Chemistry. 11 (5): 662–691. doi:10.1016/j.arabjc.2016.01.004.
6. Le Ven, J.; Schmitz-Afonso, I.; Touboul, D.; Buisson, D.; Akagah, B.; Cresteil, T.; Lewin, G. (2011). "Annonaceae fruits and parkinsonism risk: Metabolisation study of annonacin, a model neurotoxin; evaluation of human exposure". Toxicology Letters. 205: S50–S51. doi:10.1016/j.toxlet.2011.05.197.
7. Victor R. Preedy; Ronald Ross Watson; Vinood B. Patel, eds. (2011). Nuts and Seeds in Health and Disease Prevention. Academic Press. pp. 434–435.
8. Robert A. Levine; Kristy M. Richards; Kevin Tran; Rensheng Luo; Andrew L. Thomas & Robert E. Smith (2015). "Determination of Neurotoxic Acetogenins in Pawpaw (Asimina triloba) Fruit by LC-HRMS". J. Agric. Food Chem. 63 (4): 1053–1056. doi:10.1021/jf504500g. PMID 25594104.
9. Potts, L. F.; Luzzio, F. A.; Smith, S. C.; Hetman, M; Champy, P; Litvan, I (2012). "Annonacin in Asimina triloba fruit: Implication for neurotoxicity". Neurotoxicology. 33 (1): 53–8. doi:10.1016/j.neuro.2011.10.009. PMID 22130466.
10. McLaughlin, J.L. (2008). "Paw paw and cancer: annonaceous acetogenins from discovery to commercial products". Journal of Natural Products. 71 (7): 1311–21. doi:10.1021/np800191t. PMID 18598079.
11. Eposti, M (1 July 1994). "Natural substances (acetogenins) from the family Annonaceae are powerful inhibitors of mitochondrial NADH dehydrogenase (Complex I)". Biochemical Journal. 301 (1): 161–167. doi:10.1042/bj3010161. PMC 1137156. PMID 8037664.

External links

• Media related to Acetogenins at Wikimedia Commons