Fabrication of zeolite‐like metal–organic frameworks (ZMOFs) for advanced applications, such as enzyme immobilization, is of great interest but is a great synthetic challenge. Herein, we have developed a new strategy using proteins as structure‐directed agents to direct the formation of new ZMOFs that can act as versatile platforms for the in situ encapsulation of proteins under ambient conditions. Notably, protein incorporation directs the formation of a ZMOF with a sodalite (sod) topology instead of a non‐porous diamondoid (dia) topology under analogous synthetic conditions. Histidines in proteins play a crucial role in the observed templating effect. Modulating histidine content thereby influenced the resultant MOF product (from dia to dia + sod mixture and, ultimately, to sod MOF). Moreover, the resulting ZMOF‐incorporated proteins preserved their activity even after exposure to high temperatures and organic solvents, demonstrating their potential for biocatalysis and biopharmaceutical applications.
Er 3 + / Yb 3 + codoped transparent phosphate precursor glasses and glass ceramics have been fabricated and characterized. The formation of ErPO4 and YbPO4 nanocrystals was studied using x-ray diffraction. The intensity parameters, the spontaneous radiative transition probabilities, the branching ratios, and the radiative lifetimes of Er3+ in both glass ceramics and precursor glasses were calculated based on the Judd–Ofelt theory, and the crystallization process in the glass ceramics is confirmed by the optical parameters obtained. Under 975 nm wavelength excitation intense 1.54 μm fluorescence and upconversion luminescence were observed in the glass ceramics, the quantum efficiency of the Er3+ I413/2→I415/2 transition is 95%, and the transition mechanisms of the upconversion luminescence are due to a two-photon process.
A new strategy featuring an iridium-catalyzed asymmetric hydrogenation of a racemic ketone via dynamic kinetic resolution to generate a cyclopentanol with three contiguous stereocenters and a SmI2-promoted pinacol coupling to install the six-membered ring with correct stereochemistry has been described for the enantioselective total synthesis of (-)-hamigeran B (19 steps, 10.6% overall yield) and (-)-4-bromohamigeran B (19 steps, 12.3% overall yield).
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