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Zhang ZJ, Jiang S, Zhao QS. The Chemistry and Biology of Lycopodium Alkaloids. Chem Biodivers 2024; 21:e202400954. [PMID: 38844419 DOI: 10.1002/cbdv.202400954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2024] [Accepted: 06/06/2024] [Indexed: 08/02/2024]
Abstract
Lycopodiales, an order comprising 388 distinct species, is the source of Lycopodium alkaloids (LAs), a group of naturally occurring alkaloids that share a common biosynthesis and structural attributes. These remarkable organisms are considered vestiges of ancient ferns, with fossil evidence dating their existence back to an impressive 300 million years. LAs usually are tricyclic or tetracyclic compounds with C16N or C16N2 skeleton. But then there are also have a few C11N, C15N, C15N2, C22N2, and C27N3 skeleton. LAs have attracted much scientific attention because of their important biological activities related to acetylcholinesterase and unique structural characteristics. From 1881 to December 2023, there are 593 LAs from 49 species of Lycopodiales have been reported. Because the total amount of LAs is nearly five times that of 1994, the classification and group allocation of some newly isolated LAs is often challenging and not unambiguous by Ayer's simple classification. This review makes a more systematic and detailed classification for it and provides extensive coverage of naturally occurring LAs discovered from 1881 to December 2023. Until now, there is no comprehensively summary of biological activity of the LAs. This review is the first time covered the biological activity of the all LAs.
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Affiliation(s)
- Zhi-Jun Zhang
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, People's Republic of China
| | - Shuai Jiang
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, People's Republic of China
| | - Qin-Shi Zhao
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, People's Republic of China
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Jiang S, Gao BB, Ou YF, Zhao QS. Lycopodium alkaloids from Huperzia serrata and their cholinesterase inhibitory activities. PHYTOCHEMISTRY 2024; 223:114114. [PMID: 38697240 DOI: 10.1016/j.phytochem.2024.114114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 04/15/2024] [Accepted: 04/28/2024] [Indexed: 05/04/2024]
Abstract
Huperzia serrata, belonging to the Lycopodiaceae family, has been traditionally utilized for the management of treating rheumatic numbness, arthritic pain, dysmenorrhea, and contusions. This plant is a rich source of lycopodium alkaloids, some of which have demonstrated notable cholinesterase inhibitory activity. The objective of this study was to identify lycopodium alkaloids with cholinesterase inhibitory properties from H. serrata. The structures of these alkaloids were elucidated by HRESIMS, NMR (including a 1H-15N HMBC experiment), ECD methods and single-crystal X-ray diffraction. The inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) were assessed using a modified Ellman's method. Consequently, sixteen lycopodium alkaloids (1-16), including ten previously undescribed ones named huperradines A-G and huperradines I-K (1-7 and 9-11), along with one previously undescribed naturally occurring compound, huperradine H (8), were isolated from H. serrata. Among these, compounds 7 and 1 exhibited potent and moderate AChE inhibition, with IC50 values of 0.876 ± 0.039 μM and 13.125 ± 0.521 μM, respectively. Our results suggest that huperradine G (7) may be a promising lead compound for the development of new AChE inhibitors for Alzheimer's disease.
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Affiliation(s)
- Shuai Jiang
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Bei-Bei Gao
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Yu-Fei Ou
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Qin-Shi Zhao
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
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Jiang S, Li WY, Gao BB, Ou YF, Yuan ZF, Zhao QS. Casuattimines A-N, fourteen new Lycopodium alkaloids from Lycopodiastrum casuarinoides with Ca v3.1 channel inhibitory activity. Bioorg Chem 2024; 142:106962. [PMID: 37992623 DOI: 10.1016/j.bioorg.2023.106962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/28/2023] [Accepted: 11/07/2023] [Indexed: 11/24/2023]
Abstract
Two new dimeric Lycopodium alkaloids, casuattimines A and B (1 and 2), along with twelve previously undescribed Lycopodium alkaloids, casuattimines C-N (3-14), and eight known Lycopodium alkaloids, were isolated from Lycopodiastrum casuarinoides. Casuattimines A and B (1 and 2) are the first two ether-linked Lycopodium alkaloid dimers. Casuattimines C and D (3 and 4) are unique Lycopodium alkaloids characterized by a long fatty acid chain. Structural elucidation was achieved through HRESIMS, NMR, and electronic circular dichroism (ECD) calculations. In addition, the absolute configurations of compounds 7, 13, and 14 were determined by single crystal X-ray diffraction. Compounds 1, 2, and 4 demonstrated notable Cav3.1 channel inhibitory activities presenting IC50 values of 10.75 ± 1.02 μM, 9.33 ± 0.79 μM, and 7.14 ± 0.86 μM, respectively. The dynamics of compound 4 against the Cav3.1 channel and preliminary structure-activity relationships of these active Lycopodium alkaloids were also discussed.
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Affiliation(s)
- Shuai Jiang
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wen-Yan Li
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bei-Bei Gao
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu-Fei Ou
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zai-Feng Yuan
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qin-Shi Zhao
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Nett RS, Dho Y, Tsai C, Passow D, Martinez Grundman J, Low YY, Sattely ES. Plant carbonic anhydrase-like enzymes in neuroactive alkaloid biosynthesis. Nature 2023; 624:182-191. [PMID: 37938780 PMCID: PMC10700139 DOI: 10.1038/s41586-023-06716-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Accepted: 10/04/2023] [Indexed: 11/09/2023]
Abstract
Plants synthesize numerous alkaloids that mimic animal neurotransmitters1. The diversity of alkaloid structures is achieved through the generation and tailoring of unique carbon scaffolds2,3, yet many neuroactive alkaloids belong to a scaffold class for which no biosynthetic route or enzyme catalyst is known. By studying highly coordinated, tissue-specific gene expression in plants that produce neuroactive Lycopodium alkaloids4, we identified an unexpected enzyme class for alkaloid biosynthesis: neofunctionalized α-carbonic anhydrases (CAHs). We show that three CAH-like (CAL) proteins are required in the biosynthetic route to a key precursor of the Lycopodium alkaloids by catalysing a stereospecific Mannich-like condensation and subsequent bicyclic scaffold generation. Also, we describe a series of scaffold tailoring steps that generate the optimized acetylcholinesterase inhibition activity of huperzine A5. Our findings suggest a broader involvement of CAH-like enzymes in specialized metabolism and demonstrate how successive scaffold tailoring can drive potency against a neurological protein target.
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Affiliation(s)
- Ryan S Nett
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA.
- HHMI, Stanford University, Stanford, CA, USA.
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA.
| | - Yaereen Dho
- Department of Chemistry, Stanford University, Stanford, CA, USA
| | - Chun Tsai
- HHMI, Stanford University, Stanford, CA, USA
| | - Daria Passow
- Biophysics Program, Stanford University, Stanford, CA, USA
| | | | - Yun-Yee Low
- Department of Chemistry, Faculty of Science, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Elizabeth S Sattely
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA.
- HHMI, Stanford University, Stanford, CA, USA.
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Japonisine A, a fawcettimine-type Lycopodium alkaloid with an unusual skeleton from Lycopodium japonicum Thunb. Fitoterapia 2021; 156:105069. [PMID: 34743932 DOI: 10.1016/j.fitote.2021.105069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 10/21/2021] [Accepted: 10/22/2021] [Indexed: 12/22/2022]
Abstract
Japonisine A, a novel fawcettimine-type Lycopodium alkaloid with an unusual skeleton and two new fawcettimine-type ones, along with 20 known Lycopodium alkaloids, were isolated from the whole plants of Lycopodium japonicum Thunb. Their structures were determined by extensive spectroscopic analysis, including 1D and 2D NMR, and HR-ESIMS, as well as by comparison with the literature data. Notably, japonisine A (1) was the first example of fawcettimine-related Lycopodium alkaloid with a 2-oxopropyl attached at C-6. All the isolates were evaluated for their inhibitory effects on acetylcholinesterase (AChE) and α-glucosidase. Unfortunately, the results indicated that all the compounds were inactive against the acetylcholinesterase (AChE) and α-glucosidase.
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Monoterpene Indole Alkaloids with Ca v3.1 T-Type Calcium Channel Inhibitory Activity from Catharanthus roseus. Molecules 2021; 26:molecules26216516. [PMID: 34770935 PMCID: PMC8587030 DOI: 10.3390/molecules26216516] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/08/2021] [Accepted: 10/25/2021] [Indexed: 12/02/2022] Open
Abstract
Catharanthus roseus is a well-known traditional herbal medicine for the treatment of cancer, hypertension, scald, and sore in China. Phytochemical investigation on the twigs and leaves of this species led to the isolation of two new monoterpene indole alkaloids, catharanosines A (1) and B (2), and six known analogues (3–8). Structures of 1 and 2 were established by 1H-, 13C- and 2D-NMR, and HREIMS data. The absolute configuration of 1 was confirmed by single-crystal X-ray diffraction analysis. Compound 2 represented an unprecedented aspidosperma-type alkaloid with a 2-piperidinyl moiety at C-10. Compounds 6–8 exhibited remarkable Cav3.1 low voltage-gated calcium channel (LVGCC) inhibitory activity with IC50 values of 11.83 ± 1.02, 14.3 ± 1.20, and 14.54 ± 0.99 μM, respectively.
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Ma D, Martin BS, Gallagher KS, Saito T, Dai M. One-Carbon Insertion and Polarity Inversion Enabled a Pyrrole Strategy to the Total Syntheses of Pyridine-Containing Lycopodium Alkaloids: Complanadine A and Lycodine. J Am Chem Soc 2021; 143:16383-16387. [PMID: 34570487 PMCID: PMC9123642 DOI: 10.1021/jacs.1c08626] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Complanadine A and lycodine are representative members of the Lycopodium alkaloids with a characteristic pyridine-containing tetracyclic skeleton. Complanadine A has demonstrated promising neurotrophic activity and potential for persistent pain management. Herein we report a pyrrole strategy enabled by one-carbon insertion and polarity inversion for concise total syntheses of complanadine A and lycodine. The use of a pyrrole as the pyridine precursor allowed the rapid construction of their tetracyclic skeleton via a one-pot Staudinger reduction, amine-ketone condensation, and Mannich-type cyclization. The pyrrole group was then converted to the desired pyridine by the Ciamician-Dennstedt rearrangement via a one-carbon insertion process, which also simultaneously introduced a chloride at C3 for the next C-H arylation. Other key steps include a direct anti-Markovnikov hydroazidation, a Mukaiyama-Michael addition, and a Paal-Knorr pyrrole synthesis. Lycodine and complanadine A were prepared in 8 and 11 steps, respectively, from a readily available known compound.
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Affiliation(s)
| | | | - Katelyn S. Gallagher
- Department of Chemistry and Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907, United States
| | - Takeru Saito
- Department of Chemistry and Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907, United States
| | - Mingji Dai
- Department of Chemistry and Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907, United States
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A metabolic regulon reveals early and late acting enzymes in neuroactive Lycopodium alkaloid biosynthesis. Proc Natl Acad Sci U S A 2021; 118:2102949118. [PMID: 34112718 DOI: 10.1073/pnas.2102949118] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Plants synthesize many diverse small molecules that affect function of the mammalian central nervous system, making them crucial sources of therapeutics for neurological disorders. A notable portion of neuroactive phytochemicals are lysine-derived alkaloids, but the mechanisms by which plants produce these compounds have remained largely unexplored. To better understand how plants synthesize these metabolites, we focused on biosynthesis of the Lycopodium alkaloids that are produced by club mosses, a clade of plants used traditionally as herbal medicines. Hundreds of Lycopodium alkaloids have been described, including huperzine A (HupA), an acetylcholine esterase inhibitor that has generated interest as a treatment for the symptoms of Alzheimer's disease. Through combined metabolomic profiling and transcriptomics, we have identified a developmentally controlled set of biosynthetic genes, or potential regulon, for the Lycopodium alkaloids. The discovery of this putative regulon facilitated the biosynthetic reconstitution and functional characterization of six enzymes that act in the initiation and conclusion of HupA biosynthesis. This includes a type III polyketide synthase that catalyzes a crucial imine-polyketide condensation, as well as three Fe(II)/2-oxoglutarate-dependent dioxygenase (2OGD) enzymes that catalyze transformations (pyridone ring-forming desaturation, piperidine ring cleavage, and redox-neutral isomerization) within downstream HupA biosynthesis. Our results expand the diversity of known chemical transformations catalyzed by 2OGDs and provide mechanistic insight into the function of noncanonical type III PKS enzymes that generate plant alkaloid scaffolds. These data offer insight into the chemical logic of Lys-derived alkaloid biosynthesis and demonstrate the tightly coordinated coexpression of secondary metabolic genes for the biosynthesis of medicinal alkaloids.
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Haley HS, Payer SE, Papidocha SM, Clemens S, Nyenhuis J, Sarpong R. Bioinspired Diversification Approach Toward the Total Synthesis of Lycodine-Type Alkaloids. J Am Chem Soc 2021; 143:4732-4740. [PMID: 33729783 PMCID: PMC8017526 DOI: 10.1021/jacs.1c00457] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Indexed: 12/31/2022]
Abstract
Nitrogen heterocycles (azacycles) are common structural motifs in numerous pharmaceuticals, agrochemicals, and natural products. Many powerful methods have been developed and continue to be advanced for the selective installation and modification of nitrogen heterocycles through C-H functionalization and C-C cleavage approaches, revealing new strategies for the synthesis of targets containing these structural entities. Here, we report the first total syntheses of the lycodine-type Lycopodium alkaloids casuarinine H, lycoplatyrine B, lycoplatyrine A, and lycopladine F as well as the total synthesis of 8,15-dihydrohuperzine A through bioinspired late-stage diversification of a readily accessible common precursor, N-desmethyl-β-obscurine. Key steps in the syntheses include oxidative C-C bond cleavage of a piperidine ring in the core structure of the obscurine intermediate and site-selective C-H borylation of a pyridine nucleus to enable cross-coupling reactions.
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Affiliation(s)
| | | | | | | | | | - Richmond Sarpong
- Department of Chemistry, University
of California, Berkeley, California 94720, United States
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Tuzimski T, Petruczynik A. Application of HPLC-DAD for In Vitro Investigation of Acetylcholinesterase Inhibition Activity of Selected Isoquinoline Alkaloids from Sanguinaria canadensis Extracts. Molecules 2021; 26:molecules26010230. [PMID: 33466254 PMCID: PMC7796366 DOI: 10.3390/molecules26010230] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 12/30/2020] [Accepted: 01/01/2021] [Indexed: 12/17/2022] Open
Abstract
Isoquinoline alkaloids may have a wide range of pharmacological activities. Some of them have acetylcholinesterase activity inhibition. Nowadays, neurodegenerative disorders such as Alzheimer’s disease have become a serious public health problem. Searching for new effective compounds with inhibited acetylcholinesterase activity is one of the most significant challenges of modern scientific research. The aim of this study was the in vitro investigation of acetylcholinesterase activity inhibition of extracts obtained from Sanguinaria canadensis collected before, during and after flowering. The acetylcholinesterase activity inhibition of these extracts has not been previously tested. The aim was also to quantify selected alkaloids in the investigated extracts by high performance liquid chromatography (HPLC). The analyses of alkaloid content were performed using HPLC in reversed phase (RP) mode using Polar RP column and mobile phase containing acetonitrile, water and ionic liquid (IL). The acetylcholinesterase activity inhibition of the tested plant extracts and respective alkaloid standards were examined using high performance liquid chromatography with diode-array detector (HPLC-DAD) for the quantification of 5-thio-2-nitro-benzoic acid, which is the product of the reaction between the thiocholine (product of the hydrolysis of acetylthiocholine reaction) with Ellman reagent. The application of the HPLC method allowed for elimination of absorption of interfering components, for example, alkaloids such as sanguinarine and berberine. It is revealed that the HPLC method can be successfully used for the evaluation of the acetylcholinesterase inhibitory activity in samples such as plant extracts, especially those containing colored components adsorbing at wavelength in the range 405–412 nm. The acetylcholinesterase inhibition activity synergy of pairs of alkaloid standards and mixture of all investigated alkaloids was also determined. Most investigated alkaloids and all Sanguinaria canadensis extracts exhibited very high acetylcholinesterase activity inhibition. IC50 values obtained for alkaloid standards were from 0.36 for berberine to 23.13 µg/mL for protopine and from 61.24 to 89.14 µg/mL for Sanguinaria canadensis extracts. Our investigations demonstrated that these plant extracts can be recommended for further in vivo experiments to confirm their acetylcholinesterase activity inhibition.
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Affiliation(s)
- Tomasz Tuzimski
- Department of Physical Chemistry, Medical University of Lublin, Chodźki 4a, 20-093 Lublin, Poland
- Correspondence: (T.T.); (A.P.); Tel.: +48-664772307 (T.T.); +48-510664914 (A.P.)
| | - Anna Petruczynik
- Department of Inorganic Chemistry, Medical University of Lublin, Chodźki 4a, 20-093 Lublin, Poland
- Correspondence: (T.T.); (A.P.); Tel.: +48-664772307 (T.T.); +48-510664914 (A.P.)
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Recently isolated lycodine-type Lycopodium alkaloids and their total synthesis: a review. FUTURE JOURNAL OF PHARMACEUTICAL SCIENCES 2020. [DOI: 10.1186/s43094-020-00108-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Since long back, several plants species belonging to family Lycopodiaceae or Huperziaceae are being traditionally used in treatment of diseases like Alzheimer’s disease and myasthenia gravis. In 1986, huperzine A, structurally lycodine type of alkaloid was isolated and established as potent acetylcholine esterase inhibitor. Hence, further, in pursuit of similar compounds, several hundreds of different types of lycopodium alkaloids have been isolated from different Lycopodiaceae or Huperziaceae plants species.
Main body
For few of these recently isolated alkaloids, the possible mechanisms of their biosynthesis have been proposed while few of them were tried for their laboratory total asymmetric synthesis. This review summarized lycodine-type Lycopodium alkaloids, whose isolation, biosynthesis, and total synthesis have been reported after 2000. It also includes structure–activity relationship.
Short conclusion
More than 40 lycodine-type alkaloids have been isolated and structurally elucidated since 2000. Their biosynthetic pathway suggested that they got biosynthesized from lysine, while structure–activity relationship established the structural requirement of lycodine-type alkaloids to possess potent acetylcholine esterase inhibitory activity.
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