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941.
Marta-Lisette Pikma Dr. Märt Lõkov Dr. Sofja Tshepelevitsh Jaan Saame Tõiv Haljasorg Dr. Lauri Toom Dr. Sigrid Selberg Prof. Ivo Leito Assoc. Prof. Agnes Kütt 《European journal of organic chemistry》2023,26(28):e202300453
A new group of bases with benzophenoneiminyl (bpi) moiety has been synthesized and characterized in this work. The title compound tris(benzophenoneimino)phosphane (P(bpi)3) 1 was prepared with a convenient one-pot approach: benzophenone imine was deprotonated using MeMgCl and reacted with PBr3 in diglyme. The method could be considered as a method of choice for preparing other (amino)phosphanes in case lithio-intermediates and/or protonated phosphane is out of consideration. Phosphane 1 is further used to prepare a range of related phosphonium cations and phosphazenes. Phosphonium cations were deprotonated to assess the stability of the resulting phosphonium ylides. In some cases, the bulky substances were capable of forming P−N heterocycles. Experimental (MeCN) and computational (MeCN, THF, gas-phase) basicities of benzophenone imine, phosphane 1 , phosphonium ylides, and phosphazenes, as well as some representative XRD structures, are presented and discussed. 相似文献
942.
4OR - In the rectilinear picture compression problem we aim at selecting a minimum number of rectangular submatrices of a binary matrix $$M\in \{0,1\}^{m\times n}$$ , such that (a) every submatrix... 相似文献
943.
Ciglenečki Irena Orlović-Leko Palma Vidović Kristijan Simonović Niki Marguš Marija Dautović Jelena Mateša Sarah Galić Ivo 《Journal of Solid State Electrochemistry》2023,27(7):1781-1793
Journal of Solid State Electrochemistry - This paper describes the application of a methodology, which primarily involves low-cost voltammetry, to rapidly track the reactivity (i.e. surfactant... 相似文献
944.
Víctor D. Lechuga-Islas Melisa Trejo-Maldonado Ilya Anufriev Ivo Nischang İpek Terzioğlu Jens Ulbrich Ramiro Guerrero-Santos Luis E. Elizalde-Herrera Ulrich S. Schubert Carlos Guerrero-Sánchez 《Macromolecular bioscience》2023,23(1):2200262
All-aqueous, surfactant-free, and pH-driven nanoformulation methods to generate pH- and temperature-responsive polymer nanoparticles (NPs) are described. Copolymers comprising a poly(methyl methacrylate) (PMMA) backbone with a few units of 2-(dimethylamino)ethyl methacrylate (DMAEMA) are solubilized in acidic buffer (pH 2.0) to produce pH-sensitive NPs. Copolymers of different molar mass (2.3–11.5 kg mol−1) and DMAEMA composition (7.3–14.2 mol%) are evaluated using a “conventional” pH-driven nanoformulation method (i.e., adding an aqueous polymer solution (acidic buffer) into an aqueous non-solvent (basic buffer)) and a robotized method for pH adjustment of polymer dispersions. Dynamic light scattering, zeta-potential (ζ), and sedimentation-diffusion analyses suggest the formation of dual-responsive NPs of tunable size (from 20 to 110 nm) being stable for at least 28 days in the pH and temperature intervals from 2.0 to 6.0 and 25 to 50 °C, respectively. Ultraviolet-visible spectroscopic experiments show that these NPs can act as nanocarriers for the pH-sensitive dipyridamole drug, expanding its bioavailability and potential controlled release as a function of pH and temperature. These approaches offer alternative strategies to prepare stimuli-responsive NPs, avoiding the use of harmful solvents and complex purification steps, and improving the availability of biocompatible polymer nanoformulations for specific controlled release of pH-sensitive cargos. 相似文献