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We report a two-step approach to bicyclic and monocyclic 5-(1-alkoxyalkylidene)tetronates starting from lactones/esters. The method features the use of thionolactones and thionoesters as activated forms of lactones/esters that allows the direct condensation with tetronates via one-pot enolate formation, nucleophilic addition, S-methylation, and DBU-promoted elimination. The value of the method was demonstrated by the stereoselective syntheses of two natural products 5,6-Z-fadyenolide (Z/E ratio = 61) and 9,10-methylenedioxy-5,6-Z-fadyenolide (Z/E ratio = 91).Low-temperature soft chemical synthesis routes to transition-metal nitrides are of interest as an alternative to conventional high-temperature ammonolysis reactions involving large volumes of chemotoxic NH3 gas. One such method is the reaction between metal oxides and NaNH2 at ca. 200 °C to yield the counterpart nitrides; however, there remains uncertainty regarding the reaction mechanism and product phase assemblage (in particular, noncrystalline components). Here, we extend the chemical tool box and mechanistic understanding of such reactions, demonstrating the nitridation of Fe3O4 by reaction with NaNH2 at 170-190 °C, via a pseudomorphic reaction. The more reduced Fe3O4 precursor enabled nitride formation at lower temperatures than the previously reported equivalent reaction with Fe2O3. The product phase assemblage, characterized by X-ray diffraction, thermogravimetric analysis, and 57Fe Mössbauer spectroscopy, comprised 49-59 mol % ε-Fe2+xN, accompanied by 29-39 mol % FeO1-xN x and 8-14 mol % γ″-FeN. The oxynitride phase was apparently noncrystalline in the recovered product but could be crystallized by heating at 180 °C. Although synthesis of transition-metal nitrides is achieved by reaction of the counterpart oxide with NaNH2, it is evident from this investigation that the product phase assemblage may be complex, which could prove a limitation if the objective is to produce a single-phase product with well-defined electrical, magnetic, or other physical properties for applications. However, the significant yield of the FeO1-xN x oxynitride phase identified in this study opens the possibility for the synthesis of metastable oxynitride phases in high yield, by reaction of a metal oxide substrate with NaNH2, with either careful control of H2O concentration in the system or postsynthetic hydrolysis and crystallization.3,4-Dimercaptophenylalanines and 2,3-dimercaptophenylalanines have been synthesized for the first time by nucleophilic substitution of a protected aminomalonate on 3,4- and 2,3-dimercaptobenzyl bromide derivatives. The dithiol functions were protected as thioketals, and the key precursors, diphenylthioketal-protected dimercaptobenzyl bromides, were synthesized via two distinct routes from either dihydroxy benzoates or toluene-3,4-dithiol. Racemic mixtures of the fully protected amino acids were separated by chiral HPLC into the corresponding enantiomers. The absolute configuration of both 3,4- and 2,3-analogues could be assigned based on X-ray crystallography and VCD/DFT measurements. Thioketal groups were deprotected upon reaction with mercury oxide and aqueous tetrafluoroboric acid followed by treatment with H2S gas under an argon atmosphere to obtain the corresponding dimercapto amino acids. The optically pure l-Fmoc-protected 3,4-analogue (S- enantiomer) was successfully incorporated into a decapeptide using standard solid-phase peptide synthesis. Rapamycin in vivo Therefore, dithiolene-functionalized peptides are now accessible from a simple synthetic procedure, and this should afford new molecular tools for research into the catalysis, diagnostic, and nanotechnology fields.Two-dimensional covalent organic frameworks (2D-COFs) may serve as an emerging family of catalysts with well-defined atomic structures. However, the severe stacking of 2D nanosheets and large intrinsic bandgaps significantly impair their catalytic performance. Here, we report coaxial one-dimensional van der Waals heterostructures (1D vdWHs) comprised of a carbon nanotube (CNT) core and a thickness tunable thienothiophene-pyrene COF shell using a solution-based in situ wrapping method. Density functional theory calculations and operando and ex situ spectroscopic analysis indicate that carbon-sulfur regions in thienothiophene groups in the COF serve as an active catalytic site for oxygen reduction and evolution reactions. The coaxial structure enables n-doping from the CNT core to the COF shell, which is controllable by varying COF shell thickness. The charge transfer from CNTs lowers COF’s bandgap and work function, which reduces the charge transfer barrier between the active catalytic sites and adsorbed oxygen intermediates, resulting in dramatically enhanced catalytic activity. The 1D vdWHs were applied as a bifunctional oxygen electrocatalyst in rechargeable zinc-air batteries, delivering a high specific capacity of 696 mAh gZn-1 under a high current density of 40 mA cm-2 and excellent cycling stability. The 1D vdWHs based on the coaxial structure of 2D COF wrapped around CNT cores may be further used as versatile building units to create multidimensional vdWHs for exploring fundamental physics and chemistry as well as practical applications in electrochemistry, electronics, photonics, and beyond.Phosphorene is a novel two-dimensional nanomaterial with a puckered surface morphology, which has broad potential application prospects in the fields of biology and medicine. Phosphorene nanosheets are easily oxidized and form phosphorene oxide (PO) in an aerobic environment, whose biological effect remains unknown. In this paper, using large-scale molecular dynamics simulations, we show that the PO nanosheets can penetrate into and destructively extract large amounts of phospholipids from the lipid membrane. The PO nanosheets with a higher oxidation concentration have less extraction of phospholipids, while its oxidation mode has no effect on the extraction of phospholipids. Moreover, inserting PO nanosheets into the lipid membrane can enhance the diffusion of phospholipids on the membrane. These findings can shed light on understanding/designing the membrane-nanomaterial interactions.