Peyssonnosides A-B, Unusual Diterpene Glycosides with a Sterically Encumbered Cyclopropane Motif: Structure Elucidation Using an Integrated Spectroscopic and Computational Workflow.
Bhuwan Khatri ChhetriSerge LavoieAnne Marie Sweeney-JonesNazia MojibVijay RaghavanKerstin GagaringBrandon DaleCase W McNamaraKaty SoapiCassandra L QuavePrasad L PolavarapuJulia KubanekPublished in: The Journal of organic chemistry (2019)
Two sulfated diterpene glycosides featuring a highly substituted and sterically encumbered cyclopropane ring have been isolated from the marine red alga Peyssonnelia sp. Combination of a wide array of 2D NMR spectroscopic experiments, in a systematic structure elucidation workflow, revealed that peyssonnosides A-B (1-2) represent a new class of diterpene glycosides with a tetracyclo [7.5.0.01,10.05,9] tetradecane architecture. A salient feature of this workflow is the unique application of quantitative interproton distances obtained from the rotating frame Overhauser effect spectroscopy (ROESY) NMR experiment, wherein the β-d-glucose moiety of 1 was used as an internal probe to unequivocally determine the absolute configuration, which was also supported by optical rotatory dispersion (ORD). Peyssonnoside A (1) exhibited promising activity against liver stage Plasmodium berghei and moderate antimethicillin-resistant Staphylococcus aureus (MRSA) activity, with no cytotoxicity against human keratinocytes. Additionally, 1 showed strong growth inhibition of the marine fungus Dendryphiella salina indicating an antifungal ecological role in its natural environment. The high natural abundance and novel carbon skeleton of 1 suggests a rare terpene cyclase machinery, exemplifying the chemical diversity in this phylogenetically distinct marine red alga.
Keyphrases
- high resolution
- staphylococcus aureus
- molecular docking
- solid state
- electronic health record
- endothelial cells
- magnetic resonance
- methicillin resistant staphylococcus aureus
- mass spectrometry
- machine learning
- deep learning
- high speed
- biofilm formation
- climate change
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- induced pluripotent stem cells
- metabolic syndrome
- blood glucose
- quantum dots
- escherichia coli
- pseudomonas aeruginosa
- living cells
- skeletal muscle
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- pluripotent stem cells
- molecular dynamics simulations
- adipose tissue
- human health
- antibiotic resistance genes
- neural network