A new picrotoxane terpenoid glycoside, austrobuxusin N (), together with four known compounds, austrobuxusin A-D (-), were isolated from the leaves of the Australian endemic plant (Beuzev. & C.T. White) Airy Shaw. The chemical structure of was elucidated by 1D- and 2D-NMR spectroscopy, along with MS data. The sugar moiety in was determined to be -D-glucose by acid hydrolysis and subsequent comparison of its specific rotation with that of standard. The relative configuration of the aglycone was assigned by ROESY NMR experiment and density functional theory (DFT) calculation of NMR data coupled with DP4 analysis. Cytotoxicity test revealed that compound exhibited 71% inhibition against Caco-2 cell line at the concentration of 166 µM.[Formula: see text].
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http://dx.doi.org/10.1080/14786419.2021.1923710 | DOI Listing |
Bioorg Chem
January 2025
Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address:
Twelve picrotoxane-type sesquiterpenoids were isolated from Dendrobium wardianum, of which dendrowardins K-N (1-4) are new compounds and dendrowardins O and P (9, 10) are new natural products. Notably, the structure of dendrowardin K contains the rarely observed 10,11-γ-lactone ring. The structural configurations of these compounds were determined through comprehensive 1D and 2D nuclear magnetic resonance (NMR), single-crystal X-ray diffraction, and other spectroscopic analyses.
View Article and Find Full Text PDFBioorg Chem
January 2025
Center for Pharmaceutical Sciences, Faculty of Life Science and Technology, Kunming University of Science and Technology, Chenggong Campus, Kunming 650500, PR China. Electronic address:
A phytochemical investigation of the ethanol extract from air-dried stems of Baccaurea ramiflora led to the isolation of four highly oxygenated picrotoxane-type sesquiterpenoids, ramifloraolides A - D (1-4). Their structures were elucidated by comprehensive spectroscopic data (HRESIMS, IR, 1D, and 2D NMR), and their absolute configuration of them were unambiguously determined by single-crystal X-ray diffraction. Structurally, all compounds possess a unique [4.
View Article and Find Full Text PDFMolecules
August 2024
College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China.
species, which are perennial herbs widely distributed in tropical and subtropical regions, are notable for their therapeutic properties attributed to various bioactive compounds, including dendrobine-type sesquiterpenoid alkaloids (DTSAs). The objective of this review article is to provide a comprehensive overview of recent advances in the biosynthesis of DTSAs, including their extraction from species and endophytes, elucidation of associated genes through genomic and transcriptomic sequencing in both spp. and endophytes, exploration of the biosynthetic pathways of DTSAs, and drawing conclusions and outlining future perspectives in this field.
View Article and Find Full Text PDFNat Prod Rep
November 2022
Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, 22 Xinong Road, Yangling 712100, Shaanxi, People's Republic of China.
Covering: up to December 2021Picrotoxane sesquiterpenoids are a special category of natural products known to have a picrotoxane skeleton and are characterised by a highly oxidised -hydrindene core, lactone rings, and epoxide functionalities. Ever since the first picrotoxane was isolated from in the early 19 century, these compounds have long attracted the attention of natural product chemists, synthetic chemists, and pharmacologists for their particular structures and powerful biological activities. This review extensively summarizes a total of 132 naturally occurring picrotoxane sesquiterpenoids, taking into account their distributions, structural classifications, chemical and bio-synthetic researches, and bioactivities.
View Article and Find Full Text PDFChem Pharm Bull (Tokyo)
June 2022
Faculty of Science, Hokkaido University.
Picrotoxinin, coriamyrtin, and tutin are representative natural products classified as picrotoxane-type sesquiterpenes and they function as strong neurotoxins. Because they possess a cis-fused 5,6-ring skeleton with a highly congested functionalization, organic chemistry researchers have pursued the development of a stereoselective synthesis method for such skeleton. This study aims to stereoselectively synthesize the cis-fused 5,6-ring skeleton with two tetrasubstituted carbons at both angular positions using a model compound.
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