The enantioselective ring-opening reactions of methylenecyclopropanes (MCPs) involving C-C bond activation via oxidative addition of transition metals have been rarely reported. Here, we disclose a Pd/Cu-catalyzed enantio- and regioselective coupling between cyclic imino esters and MCPs to produce α-allylated 2-pyrrole derivatives. In this reaction, azomethine ylide formed by a chiral copper catalyst with ketimine ester would serve as a nucleophile to react with activated MCPs via palladium catalysis.
View Article and Find Full Text PDFThe genetic foundations underlying the observed disease resistance in certain indigenous pig breeds, notably the Min pigs of China, present a compelling underexplored subject of study. Exploring the mechanisms of disease resistance in these breeds could lay the groundwork for genetic improvements in pig immunity, potentially augmenting overall pig productivity. In this study, whole blood samples were collected from pre- and post- swine fever vaccinated Min and Large White pigs for transcriptome sequencing.
View Article and Find Full Text PDFThe organ of Corti, located in the inner ear, is the primary organ responsible for animal hearing. Each hair cell has a V-shaped or U-shaped hair bundle composed of actin-filled stereocilia and a kinocilium supported by true transport microtubules. Damage to these structures due to noise exposure, drug toxicity, aging, or environmental factors can lead to hearing loss and other disorders.
View Article and Find Full Text PDFBackground: The accessibility and outcomes of cyclin-dependent kinase 4 and 6 inhibitors (CDKi) in metastatic breast cancer (MBC) according to demographic factors are unknown.
Research Design And Methods: Retrospective review of patients with ER+ MBC prescribed first-line CDKi therapy from January 2015 through December 2022. Abstraction included time from CDKi prescription to drug initiation (TTI), time from CDKi initiation to progression (TTP), time from CDKi initiation to death or 6/30/2022, and variables (age, race, partner status, insurance type, BMI, number of comorbidities).
A small but growing set of radical SAM (-adenosyl-l-methionine) enzymes catalyze the radical mediated dehydration or dehydrogenation of 1,2-diol substrates. In some cases, these activities can be interchanged via minor structural perturbations to the reacting components raising questions regarding the relative importance of hyperconjugation, proton circulation and leaving group stability in determining the reaction outcome. The present work describes trapping and electron paramagnetic resonance (EPR) characterization of an α-hydroxyalkyl radical intermediate during dehydration and dehydrogenation of cytosylglucuronic acid and its derivatives catalyzed by the radical SAM enzyme BlsE and its Glu189Ala mutant from the blasticidin S biosynthetic pathway.
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