A rigorous proof of the selegaine structure

Yoshimura, Hitomi; Valenta, Z.; Wiesner, K.

doi:10.1016/s0040-4039(01)99306-2

Cited by 20 publications

(6 citation statements)

References 5 publications

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“…Huperzine A (HupA, selagine) and huperzine B (HupB) are two alkaloids which were first isolated from two Lycopodium species in the family Huperziaceae: Huperzia serrata and Huperzia selago (formerly known as L. selago) [1][2][3][4]. Pharmacological studies, in vitro, conducted in the search for novel drugs which would improve the symptoms of Alzheimer's disease (AD), have demonstrated that both compounds are potent and reversible acetylcholinesterase (AChE) inhibitors which cross the blood-brain barrier [5,6].…”

Section: Introductionmentioning

confidence: 99%

Huperzine A and Huperzine B Production by Prothallus Cultures of Huperzia selago (L.) Bernh. ex Schrank et Mart

et al. 2020

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This is the first report of an efficient and effective procedure to optimize the biosynthesis of huperzine A (HupA) and huperzine B (HupB) in vitro from Huperzia selago gametophytes. Axenic tissue cultures were established using spores collected from the sporophytes growing in the wild. The prothalia were obtained after 7–18 months. Approximately 90 up to 100% of the gametophytes were viable and grew rapidly after each transfer on to a fresh medium every 3 months. The best biomass growth index for prothallus calculated on a fresh (FW) and dry weight (DW) basis, at 24 weeks of culture, was 2500% (FW) and 2200% (DW), respectively. The huperzine A content in the gametophytes was very high and ranged from 0.74 mg/g to 4.73 mg/g DW. The highest yield HupA biosynthesis at >4 mg/g DW was observed on W/S medium without growth regulators at 8 to 24 weeks of culture. The highest HupB content ranged from 0.10 mg/g to 0.52 mg/g DW and was obtained on the same medium. The results demonstrate the superiority of H. selago gametophyte cultures, with the level of HupA biosynthesis approximately 42% higher compared to sporophyte cultures and 35-fold higher than when the alkaloid was isolated from H. serrata, its current source for the pharmaceutical industry. Moreover, the biosynthesis of HupB was several-fold more efficient than in H. selago sporophytes growing in the wild. HPLC-HR-MS analyses of the extracts identified eight new alkaloids previously unreported in H. selago: deacetylfawcettine, fawcettimine, 16-hydroxyhuperzine B, deacetyllycoclavine, annopodine, lycopecurine, des-N-methylfastigiatine and flabelline.

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Section: Introductionmentioning

confidence: 99%

Huperzine A and Huperzine B Production by Prothallus Cultures of Huperzia selago (L.) Bernh. ex Schrank et Mart

et al. 2020

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“…the next most abundant group; annotinine (5,6) ; and selagine (7,8). At the time of writing, annotinine and selagine are the sole reported representatives of their groups.…”

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Lycopodium Alkaloids Xiii. Mass Spectra of Representative Alkaloids

MacLean¹

1963

Can. J. Chem.

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The mass spectra of a number of Lycofiodium alkaloids are recorded and schemes proposed for their fragmentation. The loss of the bridge dominates the fragmentation process in the structural types examined.The Lycopodium alkaloids have been the subject of many studies in the past few years, but there are still many alkaloids of unknown constitution. Those alkaloids whose structures have been elucidated are, for the most part, the most abundant while those whose structure still await solution have been found in smaller quantity. The mass spectrometric method, which has been used in many recent investigations, is particularly well suited to structural studies on substances available in small a m o~n t .~ I t was of interest, therefore, to record the spectra of the Lycopodium alkaloids of known structure and t o study their fragmentation in order that the information so obtained might be applied t o the study of those alkaloids whose structures are yet unresolved and to those alkaloids yet to be isolated.The Lycopodium alkaloids which are now known may be conveniently classified for the purposes of this discussion into four groups: those related in skeletal structure to lycopodine ( 2 ) , by far the largest group; those related in skeletal structure to lycodine (3, 4),

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“…A nuclear Overhauser enhancement (nOe) experiment confirmed the proximity of the C-10 methyl (6 1.70) to the allylic C-7 hydrogen (6 3.60) and spin decoupling experiments revealed that this allylic hydrogen was coupled (J = 5 Hz) to the C-8 alkenic hydrogen. This coupling was not detected in the 60-MHz spectrum of selagine recorded by the earlier workers (1,2). The stereochemistry at C-11 was not proposed in the original papers on selagine (1, 2) but was assigned as shown in 1 on the basis of a study of the rate of methiodide formation (5).…”

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confidence: 82%

“…4 High resolution mass spectrometry (hrms) indicated a molecular formula of Cl5Hl8N2O2 and the ultraviolet (uv) spectrum (A,,, 238, 302, 33 1 nm) was very similar to that of huperzine A (2). The infrared (ir) spectrum showed characteristic a-pyridone absorption (v,,, 1664,1643, 1605,1544 cm-').…”

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confidence: 99%