We report a new family of chiral bifunctional acid/base type organocatalysts, 2-aminoDMAP/Squaramides, which are proved to be highly active (1 mol % cat. loading) promoters in conjugate addition of dibenzoylmethane to various trans-β-nitroalkenes. Steric demand of the catalysts was clearly seen by a set-by-set modulation of the squaramide unit through electronic and steric factors. The synergistic cooperation of 2-aminoDMAP “superbase” and sterically encumbered squaramide (H-bond donor) enabled complete conversion of a range of reactants into corresponding Michael adducts in a couple of hours with exquisite selectivities (up to 98% ee).
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Ann Bot
January 2025
Laboratório de Ecologia e Biogeografia de Plantas, Departamento de Biodiversidade, Setor Palotina, Universidade Federal do Paraná, Rua Pioneiro, 2153, Jardim Dallas, CEP 85950 000, Palotina, Paraná, Brazil.
Background: Epiphyllous bryophytes are a group of plants with complex adaptations to colonize the leaves of vascular plants and are considered one of the most specialized and sensitive groups to environmental changes. Despite their specificity and ecological importance, these plants represent a largely neglected group in relation to scientific research and ecological data. This lack of information directly affects our understanding of biodiversity patterns and compromises the conservation of this group in threatened ecosystems.
View Article and Find Full Text PDFCorporate Social Responsibility (CSR) refers to initiatives undertaken by corporations that aim to make a positive impact on society. It is unclear to what extent these aims are achieved in relation to population health. We explored the evidence for mechanisms by which CSR has positive or negative effects on population health through a systematic-narrative hybrid review of 97 relevant articles.
View Article and Find Full Text PDFAnal Methods
November 2017
Lab of Biosystem and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China.
As an important small molecule, adenosine triphosphate (ATP) plays an important role in the regulation of cell metabolism and supplies energy for various biochemical reactions in organisms. We herein developed a sensitive surface-enhanced Raman scattering (SERS) biosensor for highly specific detection of ATP using core-satellite assemblies. To construct the aptamer-based biosensor, a known ATP binding aptamer was divided into two segments.
View Article and Find Full Text PDFIr Vet J
January 2025
Animal and Poultry Production Division, Department of Animal and Poultry Breeding, Desert Research Center, Cairo, Egypt.
Brucellosis is a highly contagious zoonotic bacterial disease. It has considerable negative consequences on the animal production industry worldwide. The objective of this study was to investigate the genetic and molecular variations in Shami goat susceptible to Brucella infection.
View Article and Find Full Text PDFNat Struct Mol Biol
January 2025
Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Gastroenterology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
Thymidine kinase 1 (TK1), a crucial enzyme in DNA synthesis, is highly expressed in various cancers. However, the mechanisms underlying its elevated expression and the implications for tumor metabolism remain unclear. Here we demonstrate that activation of growth factor receptors enhances TK1 expression.
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