Chemoenzymatic and stereoselective total syntheses of the non-natural enantiomeric forms of the recently isolated protoilludane natural products 8-deoxydihydrotsugicoline (1) and radudiol (2) (viz. ent-1 and ent-2, respectively) are reported. The key steps involve the Diels-Alder cycloaddition of cyclopent-2-en-1-one to the acetonide derived from enantiomerically pure and enzymatically derived cis-1,2-dihydrocatechol 3, elaboration of the resulting adduct to the tricyclic ketone 12, and a photochemically promoted rearrangement of this last compound to the octahydro-1H-cyclobuta[e]indenone 13.
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Sci Rep
December 2024
Germplasm Bank of Wild Species & Yunnan Key Laboratory for Fungal Diversity and Green Development, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China.
Continuous cropping obstacle has been becoming the bottleneck for the stable development of morel cultivation. The allelopathic effect of soil allelochemicals may play an instrumental role in the morel soil sickness. In this study, the allelochemicals were identified by gas chromatography-mass spectrometry (GC-MS) combined with in vitro bioassay.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
December 2024
Department of Chemistry, COMSATS University, Abbottabad 22060, KPK, Pakistan.
The ruthenium compounds have been known to have the wide range of potential applications as anticancer, antibacterial and anti-diabetic etc. The ligand substitutions play a vital role in enhancing the pharmacological and biological activities. In the present study, three ruthenium-metal based complexes, designated as (I-III), were synthesized and characterized employing element analysis, FTIR and HNMR.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address:
Polylactic acid (PLA) is a bio-recyclable plastic, but its high flammability limits broader applications. Here, a novel flame retardant (Zn-CHP) is synthesized from chitosan (CH), diethylenetriaminepenta (methylenephosphonic) acid (DTPMP), and ZnCl₂ using a simple, solvent-free process. The Zn-CHP additive is melt-blended with PLA, achieving excellent flame retardancy at just 2 wt% loading.
View Article and Find Full Text PDFJ Echocardiogr
December 2024
Department of Cardiology, Lebanese American University Medical Center - Rizk Hospital, Beirut, Lebanon.
Left atrial strain (LAS) was recently introduced as a parameter that reflects on left atrial function. Consequently, changes in LAS can inform the development of cardiovascular diseases, hence providing a window for non-invasive and cost-effective testing of these diseases and their complications at early stages of development, potentially offering a segway towards preventive interventions. LAS has yet to be implemented into standard practice.
View Article and Find Full Text PDFJ Nat Prod
December 2024
Anti-infective Agent Creation Engineering Research Centre of Sichuan Province, School of Pharmacy, Chengdu University, Chengdu 610106, China.
The first total syntheses of four isoflavone glucosides, tectoridin (), tectoridin A (), tectorigenin 7--β-d-glucopyranosyl-12--β-d-glucopyranoside (), and isotectroigenin 7--β-d-glucopyranoside (), have been accomplished. Key steps in our synthetic approach include a regioselective halogenation reaction, followed by methanolysis to introduce the -OCH group into isoflavone frameworks and a PTC-promoted stereoselective glycosidation to establish glycosidic bonds. The synthesized isoflavone glucosides (-) and their corresponding aglycones ( and ) were evaluated for anti-inflammatory activity against nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1 β (IL-1β) in lipopolysaccharide (LPS)-induced RAW264.
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