Guaiane-type sesquiterpenoids from the roots of Stellera chamaejasme L. and their neuroprotective activities

UPLC‐Q‐TOF‐MS/MS analysis of the guaiane sesquiterpenoids oxytropiols A–J and detection of undescribed analogues from the locoweed endophytic fungus Alternaria oxytropis (Pleosporaceae)

“…Guaiane sesquiterpenoids are a large group of natural products, and the core skeleton is a five‐membered ring fused to a seven‐membered ring with two methyl groups and an isopropyl group anchored at C4/C10 and C7, respectively 1–5 . According to different ring systems, guaiane sesquiterpenoids can be generally divided into five categories: bicyclic guaiane, guaiane‐lactone, tricyclic guaiane, dimeric or trimeric guaiane, and other guaiane‐type sesquiterpenoids 4,5 .…”

“…Guaiane sesquiterpenoids are a large group of natural products, and the core skeleton is a five-membered ring fused to a seven-membered ring with two methyl groups and an isopropyl group anchored at C4/C10 and C7, respectively. [1][2][3][4][5] According to different ring systems, guaiane sesquiterpenoids can be generally divided into five categories: bicyclic guaiane, guaiane-lactone, tricyclic guaiane, dimeric or trimeric guaiane, and other guaiane-type sesquiterpenoids. 4,5 Ten undescribed bicyclic guaiane sesquiterpenoids (oxytropiols A-J, 1-10) were first isolated from the notorious locoweed endophytic fungus Alternaria oxytropis (Pleosporaceae) and were mainly elucidated by NMR and Xray analyses together with chemical derivative reactions.…”

“…[1][2][3][4][5] According to different ring systems, guaiane sesquiterpenoids can be generally divided into five categories: bicyclic guaiane, guaiane-lactone, tricyclic guaiane, dimeric or trimeric guaiane, and other guaiane-type sesquiterpenoids. 4,5 Ten undescribed bicyclic guaiane sesquiterpenoids (oxytropiols A-J, 1-10) were first isolated from the notorious locoweed endophytic fungus Alternaria oxytropis (Pleosporaceae) and were mainly elucidated by NMR and Xray analyses together with chemical derivative reactions. 6 UPLC combined with tandem mass spectrometry (MS/MS) is a sensitive and convenient method for the identification of small molecules according to the retention time, maximum UV wavelength, high-resolution mass, and fragment ions.…”

“…Oxytropiols A-K(1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11) and the crude extracts were determined by UPLC-Q-TOF-MS (Waters, USA). UPLC was carried out with a Waters Acquity UPLC-PDA system equipped with an analytical reverse-phase C18 column (100 Â 2.1 mm, 1.7 μm, Acquity BEH, Waters, USA), and the detection wavelength of the PDA detector was 200-400 nm.…”

Concise Biosynthesis of Tropone-Containing Spiromaterpenes by a Sesquiterpene Cyclase and a Multifunctional P450 from a Deep-Sea-Derived Spiromastix sp. Fungus

“…Guaiane-type sesquiterpenes are characterized by a 5/7 fused ring scaffold with two methyl and one isopropyl group and are widely distributed in nature (Figure ). They possess a wide range of bioactivities, such as AChE inhibition, anti-inflammatory, , neuroprotective, and antibiotic activities . For instance, lipidiol is a potent inhibitor of AChE with an IC 50 of 0.52 μM (Figure ).…”