The disecosteroid natural product gibbosterol A-which has a 14/5-bicyclic framework, a high oxidation state, and a twisted -9,11-epoxy motif-is the first water-soluble 5,10:8,9-disecosteroid. Herein, we report a bioinspired two-phase synthesis of this natural product in only 15 steps from inexpensive ergosterol. In the first (isomerase) phase, the core bicyclic framework is rapidly installed by the skeletal reorganization of ergosterol endoperoxide via a ruthenium-catalyzed dual C-C bond fragmentation. In the second (oxidase) phase, chemoselective, regioselective, and stereoselective redox transformations precisely introduce the requisite oxygenated functional groups. This work demonstrates that the ingenious two-phase synthesis logic that has been applied to terpenes is also a powerful strategy for steroid synthesis.
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http://dx.doi.org/10.1021/jacsau.3c00698 | DOI Listing |
JAMA Netw Open
March 2025
Department of Medical Statistics, Research and Development Center, Osaka Medical and Pharmaceutical University, Osaka, Japan.
Importance: Although evaluation of geographic area inequities in vaccination is crucial to identify areas that need community-based interventions, knowledge of disparities in human papillomavirus (HPV) vaccination uptake remains limited in Japan.
Objective: To investigate the association of female cumulative HPV vaccination uptake with neighborhood-based socioeconomic status and access indicators in Osaka City, Japan.
Design, Setting, And Participants: This population-based, cross-sectional study included HPV vaccination data for fiscal year (April 1 to March 31) 2013 to fiscal year 2022 provided by Osaka City.
Hum Vaccin Immunother
December 2025
Pfizer Vaccines, Collegeville, USA.
This systematic literature review summarizes the evidence across 56 publications and pre-prints (January 2020-July 2023) with low-risk of bias based on JBI critical appraisal, that report adjusted estimates for the relationship between COVID-19 vaccination and Post-COVID-19 Condition (PCC) by timing of vaccination relative to infection or PCC-onset. Comparisons of adjusted vaccine effectiveness (aVE) against ≥1 PCC (vs. unvaccinated) across study characteristics known to impact PCC burden or VE against other COVID-19 endpoints were possible for 31 studies where vaccination preceded infection.
View Article and Find Full Text PDFCell Transplant
March 2025
Department of Regenerative Medicine and Transplantation, Faculty of Medicine, Fukuoka University, Fukuoka, Japan.
The Japanese monkey has been used in several animal studies; however, its potential as a recipient model for xenotransplantation is unclear. The potential of the Japanese monkey as a recipient for xenotransplantation was assessed using two experimental models. The first model evaluated the optimal dose of tacrolimus without severe adverse events.
View Article and Find Full Text PDFFuture Microbiol
March 2025
Department of Biological Sciences, Missouri University of Science and Technology, Rolla, MO, USA.
Bioactive glasses (BGs) are physiologically reactive surface biomaterials widely used in biomedical applications and various treatments. Borate bioactive glasses (BBGs) are third-generation BGs, and they exhibit superior biodegradable, bioactive, osteoconductive, antibacterial, and biocompatible properties compared to other types of BGs. Certain concentrations of dopant ions can be incorporated into the chemical structure of BBGs to enhance their biological functionalities and antimicrobial properties.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
March 2025
University of South China, School of Chemistry and Chemical Engineering, 421001, Hengyang, CHINA.
The presence of sterically rigid contiguous quaternary stereocenters in natural products imposes conformational constraints with significant effects on their biological activities. However, achieving the direct synthesis of multiple contiguous quaternary stereocenters in a single step remains a formidable challenge. Here, we present the total synthesis of the antibacterial metabolite lugdunomycin (1) in thirteen steps via a sequence of photochemical transformations.
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