Oxacyclododecindione-type macrolactones exhibit highly potent anti-inflammatory activities even at nanomolar concentration. After the determination of the relative configuration of the stereocenters at C14 and C15 by total synthesis of 4-dechloro-14-deoxyoxacyclododecindione and 14-deoxyoxacyclododecindione, the absolute configuration has now been assigned by X-ray crystallography. Surprisingly, the absolute configuration is (14S,15R) which differs for C15 from that of the well-known derivatives of (S)-curvularin. The biological activities of both enantiomers of 14-deoxyoxacyclododecindione, obtained by racemic synthesis and optical resolution, were investigated and the ring conformation of the natural product was compared to that of (S)-curvularin and (R)-dehydrocurvularin.
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Bot Stud
January 2025
Institute of Fisheries Science, College of Life Science, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Da'an Dist, Taipei, 106319, Taiwan (R.O.C.).
Background: Trichoderma species, known as biocontrol agents against plant diseases, contain diverse compounds, especially terpenoids, with various bioactivities. To facilitate the exploration of bioactive secondary metabolites of Trichoderma harzianum NTU2180, the OSMAC approach MS/MS molecular networking was applied in the current study.
Results: The feature-based molecular networking (FBMN) analysis showed that T.
Chem Biodivers
January 2025
Guizhou Medical University, School of Pharmaceutical Sciences, University Town, Gui'an New District, 550025, Guiyang, CHINA.
An unrevealed dihydroflavone-monoterpene conjugate (1), two unrevealed kavalactones (2-3, including one with an uncommon side chain), and thirteen previously identified compounds (4-16) were extracted from Alpinia katsumadai Hayata. seeds. The two-dimension structures of the new compounds were authenticated utilizing HRESIMS as well as NMR spectral analysis, while their absolute chiral configurations were ascertained either by correlating the experimental and simulated values of electronic circular dichroism (ECD) patterns or conducting X-ray diffraction experiments.
View Article and Find Full Text PDFBMJ Open
December 2024
Health Policy Research Center, Guangxi Medical University, Nanning, Guangxi, China
Objective: The purpose of this study is to analyse the changes in the equity of intensive care unit (ICU) bed allocation in 14 cities in China's Guangxi Zhuang Autonomous Region from 2018 to 2021, to identify the problems in the process of ICU bed allocation in China's ethnic minority regions.
Design: The Gini coefficient, Theil index, health resource density index, and spatial correlation analysis were used to analyse the current status of ICU bed resource allocation and allocation equity in Guangxi, China, on two dimensions: geography, and population.
Setting: The Guangxi Zhuang Autonomous Region.
Spectrochim Acta A Mol Biomol Spectrosc
January 2025
Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 160 00 Prague, Czech Republic. Electronic address:
Model P-chirogenic phosphonates derived from isopinocampheol, offering an excellent experimental system for studying chirality on the phosphorus chiral center, were studied using a set of chiroptical methods including ECD, VCD and ROA. Thanks to their rigidity, limiting the number of possible conformers, we successfully correlated the experimental UV-vis/ECD, IR/VCD and Raman/ROA results with DFT calculations. This allowed us to confidently assign the absolute configuration of our models, and our assignment is consistent with X-ray diffraction (XRD) data.
View Article and Find Full Text PDFJAMA Intern Med
January 2025
Department of Behavioral Science, The University of Texas MD Anderson Cancer Center, Houston.
Importance: The optimal configuration of a smoking cessation intervention in a lung cancer screening (LCS) setting has not yet been established.
Objective: To evaluate the efficacy of 3 tobacco treatment strategies of increasing integration and intensity in the LCS setting.
Design, Setting, And Participants: In this randomized clinical trial, LCS-eligible current smokers were randomized into 3 treatments: quitline (QL), QL plus (QL+), or integrated care (IC).
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