The synthesis of unit A of the cryptophycins from (S)-trans-3-penten-2-ol and from (S)-trans-4-hexen-3-ol has been completed. The key stereodetermining step is a [2,3]-Wittig rearrangement of a propargyl ether. Elaboration of the rearrangement product was accomplished by means of a selective hydroboration-oxidation of a terminal alkyne, Horner-Emmons homologation of the derived aldehyde, followed by selective ozonolytic cleavage and Wittig olefination. This synthesis provides easy access to the series of cryptophycin analogues that incorporate a modified aromatic ring in unit A.
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http://dx.doi.org/10.1021/jo9815958 | DOI Listing |
NPJ Vaccines
December 2024
Department for Evidence-based Medicine and Evaluation, University for Continuing Education Krems (Danube University Krems), Krems, Austria.
Pneumococcal infections are a serious health issue associated with increased morbidity and mortality. This systematic review evaluated the efficacy, effectiveness, immunogenicity, and safety of the pneumococcal conjugate vaccine (PCV)15 compared to other pneumococcal vaccines or no vaccination in children and adults. We identified 20 randomized controlled trials (RCTs).
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December 2024
School of Biosciences, University of Kent, Canterbury, Kent, CT2 7NZ, UK.
Worldwide museums hold collections of eggshells representing material for descriptive studies. However, an obstacle to this is the lack of information about the original contents and weight of the entire egg (W). This study aimed to fill this gap though development of a methodological mechanism for calculating the volume of the egg interior (V), its density (D) and W.
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December 2024
Department of Microbiology, Faculty of Sciences, CEI·MAR-International Campus of Excellence in Marine Science, University of Malaga, Málaga, Spain.
The inclusion of microalgae in functional fish diets has a notable impact on the welfare, metabolism and physiology of the organism. The microbial communities associated with the fish are directly influenced by the host's diet, and further understanding the impact on mucosal microbiota is needed. This study aimed to analyze the microbiota associated with the skin and gills of Sparus aurata fed a diet containing 10% microalgae.
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December 2024
School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand.
Effector proteins secreted via the type III secretion system (T3SS) of nitrogen-fixing rhizobia are key determinants of symbiotic compatibility in legumes. Previous report revealed that the T3SS of Bradyrhizobium sp. DOA9 plays negative effects on Arachis hypogaea symbiosis.
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December 2024
Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China.
Biological systems are complex, encompassing intertwined spatial, molecular and functional features. However, methodological constraints limit the completeness of information that can be extracted. Here, we report the development of INSIHGT, a non-destructive, accessible three-dimensional (3D) spatial biology method utilizing superchaotropes and host-guest chemistry to achieve homogeneous, deep penetration of macromolecular probes up to centimeter scales, providing reliable semi-quantitative signals throughout the tissue volume.
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