Diazophosphonates, readily prepared from α-ketophosphonates by oxidation of the corresponding hydrazones in batch or in flow, are useful partners in 1,3-dipolar cycloaddition reactions to alkynes to give N-H pyrazoles, including the first intramolecular examples of such a process. The phosphoryl group imbues a number of desirable properties into the diazo 1,3-dipole. The electron-withdrawing nature of the phosphoryl stabilizes the diazo compound making it easier to handle, whilst the ability of the phosphoryl group to migrate readily in a [1,5]-sigmatropic rearrangement enables its transfer from C to N to aromatize the initial cycloadduct, and hence its facile removal from the final pyrazole product. Overall, the diazophosphonate acts as a surrogate for the much less stable diazoalkane in cycloadditions, with the phosphoryl group playing a vital, but traceless, role. The cycloaddition proceeds more readily with alkynes bearing electron-withdrawing groups, and is regiospecific with asymmetrical alkynes. The potential of diazophosphonates for use in bioorthogonal cycloadditions is demonstrated by their facile addition to strained alkynes.
Changes to the composition of the microbiome in neoplasia, is termed oncobiosis, may affect tumor behavior through the changes to the secretion of bacterial metabolites. In this study we show, that ursodeoxycholic acid (UDCA), a bacterial metabolite, has cytostatic properties in pancreatic adenocarcinoma cell (PDAC) models. UDCA in concentrations corresponding to the human serum reference range suppressed PDAC cell proliferation.
Centre for Movement Disorders, Stavanger University Hospital, Stavanger, Norway; Department of Chemistry, Bioscience and Environmental Engineering, University of Stavanger, Stavanger, Norway. Electronic address:
Introduction: Parkinson's disease (PD) is a progressive neurodegenerative disease, and biomarkers are needed to enhance earlier detection and monitoring. Alpha-synuclein, phosphorylated at serine 129 (pS129-α-syn), is the predominant form of α-syn found in Lewy bodies implicating an involvement in disease pathology. This review aims to systematically evaluate the evidence for pS129-α-syn detection in human biofluid samples of PD utilizing ELISA-based protein detection methods.
Laboratory Medicine Center, Department of Genetic and Genomic Medicine, Zhejiang Provincial People's Hospital, Affiliated People's Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China.
Background: GTPBP3 catalyzes τm(s) U biosynthesis at the 34th wobble position of mitochondrial tRNAs, the hypomodification of τmU leads to mitochondrial disease. While twenty-three variants of GTPBP3 have been reported worldwide, the genetic landscape in China remains uncertain.
Methods: By using whole-exome sequencing, the candidate individuals carrying GTPBP3 variants were screened and identified.
Alzheimer's Disease (AD) is a debilitating neurodegenerative disease that affects 47.5 million people worldwide. AD is characterised by the formation of plaques containing extracellular amyloid-β (Aβ) and neurofibrillary tangles composed of hyper-phosphorylated tau proteins (pTau).
A three-component reaction of trifluoromethyl enones, phosphine oxides, and alcohols in water solution is developed. This defluorinative reaction occurs through a cascade process involving defluorophosphorylation, defluoroalkyloxylation, and defluoroheteroannulation, enabling the modular synthesis of furans with four distinct substituents: 2-alkyloxy, 3-trifluoromethyl, 4-phosphoryl, and 5-(hetero)aryl groups. Moreover, apart from alcohol substrates, the scope of nucleophiles could be further extended to phenols, azacycles, or sulfonamide.
