This article describes the asymmetric synthesis of chiral aziridinoquinoxalines using (R)-TRIP-catalyzed parallel kinetic resolution under transfer hydrogenation conditions. This resolution was ...successfully accomplished for 16 different substrates and led to highly enantioenriched diastereomers with the (R)-configuration of the newly formed stereocenter (32–61% yield and 64–99% ee for the (R,R,R)-diastereomers and 7–46% yield and 97–99% ee for the (S,S,R)-diastereomers). This process could be coupled to ring-opening of the (S,S,R)-diastereomer with thiophenol to produce chiral tetrahydroquinoxalines with three contiguous stereocenters.
Coordinative supramolecular cages with adjustable cavities have found extensive applications in various fields, but the cavity modification strategies for multi‐functional structures are still ...challenging. Here, we present a tension‐driven self‐expansion strategy for construction of multi‐cavity cages with high structural complexity. Under the regulation of strain‐induced capping ligands, unprecedented heteromorphosis triple‐cavity cages S2/S4 were obtained based on a metallo‐organic ligand (MOL) scaffold. The heteromorphosis cages exhibited significant higher cavity diversity than the homomorphous double‐cavity cages S1/S3; all of the cages were thoroughly characterized through various analytical techniques including (1D and 2D) NMR, ESI‐MS, TWIM‐MS, AFM, and SAXS analyses. Furthermore, the encapsulation of porphyrin in the cavities of these multi‐cavity cages were investigated. This research opens up new possibilities for the architecture of heteromorphosis supramolecular cages via precisely controlled “scaffold‐capping” assembly with preorganized ligands, which could have potential applications in the development of multifunctional structures with higher complexity.
A strain‐dependent capping strategy was proposed to obtain a series of multi‐cavity cages, where dimetallic double‐cavity cages and triple‐cavity cages were formed through the geometric matching and the strain‐induced tension, respectively. This is the first time that discrete supramolecular cages with three cavities have been achieved through the application of molecular strain.
We report a protocol for alkene hydroxyalkenylation. Using a persulfate anion as a one‐electron‐oxidation reagent and 1,2‐bis(phenylsulfonyl)ethylene as a radical acceptor in the presence of water, ...alkenes were converted into the corresponding 1‐phenylsulfonyl‐4‐hydroxyalkenes in good to high yields. The hydroxyalkenylation process involves the nucleophilic hydroxylation of alkene radical cations to give β‐hydroxyalkyl radicals, which, after a radical addition/β‐elimination sequence, provide the products. We also report a photocatalytic protocol for alkoxyalkenylation.
A simple protocol for alkene hydroxyalkenylation by 1,2‐bis(phenylsulfonyl)ethylene was developed using persulfate anion as a one‐electron oxidizing reagent. Regioselective hydroxyalkenylation was observed for a variety of substituted alkenes. A photocatalytic protocol for alkoxyalkenylation using an acridinium salt was also successful.
Quantum states induced by single-atomic impurities are at the frontier of physics and material science. While such states have been reported in high-temperature superconductors and dilute magnetic ...semiconductors, they are unexplored in topological magnets which can feature spin-orbit tunability. Here we use spin-polarized scanning tunneling microscopy/spectroscopy (STM/S) to study the engineered quantum impurity in a topological magnet Co
Sn
S
. We find that each substituted In impurity introduces a striking localized bound state. Our systematic magnetization-polarized probe reveals that this bound state is spin-down polarized, in lock with a negative orbital magnetization. Moreover, the magnetic bound states of neighboring impurities interact to form quantized orbitals, exhibiting an intriguing spin-orbit splitting, analogous to the splitting of the topological fermion line. Our work collectively demonstrates the strong spin-orbit effect of the single-atomic impurity at the quantum level, suggesting that a nonmagnetic impurity can introduce spin-orbit coupled magnetic resonance in topological magnets.
By using special single-qubit measurement bases, we first proposed a bidirectional remote state preparation (BRSP) scheme to prepare two arbitrary single-qubit states in a noiseless quantum channel. ...Then, we modified it to a joint BRSP scheme and generalized it to prepare multi-qubit states. Meanwhile, we discussed the preparation fidelity of the scheme under the simulation of amplitude damping (AD) noise. In addition, we employed the weak measurement and its reversing measurements for the BRSP scheme and obtained higher fidelity of preparation results. Finally, through numerical simulation, we compared and analyzed the preparation fidelities under the above two conditions, the results of which showed that the weak measurement method was helpful in improving the proposed BRSP in the AD noise channel.
•Feed-forward measurement strategy enables 100% success rate of remote state preparation(RSP).•Our scheme only requires specific single-qubit projective measurement and Pauli operator.•We simulated the influence of amplitude damping noise on the preparation process.•Weak measurement methods can effectively improve the fidelity of this scheme.•The results of this paper provide flexible choices for RSP in different scenarios.
Mammalian pre-implantation development is a complex process involving dramatic changes in the transcriptional architecture. We report here a comprehensive analysis of transcriptome dynamics from ...oocyte to morula in both human and mouse embryos, using single-cell RNA sequencing. Based on single-nucleotide variants in human blastomere messenger RNAs and paternal-specific single-nucleotide polymorphisms, we identify novel stage-specific monoallelic expression patterns for a significant portion of polymorphic gene transcripts (25 to 53%). By weighted gene co-expression network analysis, we find that each developmental stage can be delineated concisely by a small number of functional modules of co-expressed genes. This result indicates a sequential order of transcriptional changes in pathways of cell cycle, gene regulation, translation and metabolism, acting in a step-wise fashion from cleavage to morula. Cross-species comparisons with mouse pre-implantation embryos reveal that the majority of human stage-specific modules (7 out of 9) are notably preserved, but developmental specificity and timing differ between human and mouse. Furthermore, we identify conserved key members (or hub genes) of the human and mouse networks. These genes represent novel candidates that are likely to be key in driving mammalian pre-implantation development. Together, the results provide a valuable resource to dissect gene regulatory mechanisms underlying progressive development of early mammalian embryos.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The kidney is a vital organ for the elimination of therapeutic drugs and their metabolites.Renal drug transporters,which are primarily located in the renal proximal tubules,play an important role in ...tubular secretion and reabsorption of drug molecules in the kidney.Tubular secretion is characterized by high clearance capacities,broad substrate specificities,and distinct charge selectivity for organic cations and anions.In the past two decades,substantial progress has been made in understanding the roles of transporters in drug disposition,efficacy,toxicity and drug–drug interactions(DDIs).In the kidney,several transporters are involved in renal handling of organic cation(OC) and organic anion(OA) drugs.These transporters are increasingly recognized as the target for clinically significant DDIs.This review focuses on the functional characteristics of major human renal drug transporters and their involvement in clinically significant DDIs.
Objective
Trigeminal neuralgia (TN) primarily occurs in elderly adults and is thought to be induced by neurovascular compression. However, a few children and young adults may present with the ...clinical features of TN. In this study, we aim to retrospectively assess the data of young patients with TN from a single center.
Methods
Of 783 consecutive patients with TN treated at our center between 2007 and 2017, 11 young patients under the age of 30 years with TN met the inclusion criteria and were enrolled. Their clinical records, surgical treatments, and long-term outcomes were obtained and analyzed.
Results
All the 11 patients with TN underwent microvascular decompression (MVD). The average age at symptom onset was 24 years (range, 14–29 years), and the average age at the time of surgery was 28.9 years (range, 25–35 years). Further, 5 patients had left-sided symptoms, and 6 had right-sided symptoms. Surgery revealed only venous compression in 3 patients, only arterial compression in 5 patients, and both venous and arterial compression in 3 patients. The average duration of symptoms was 4.9 years, and the average follow-up duration was 7.4 years (range, 4.5–12.9 years). The long-term outcome was excellent in 9 patients and good in 2 patients, and there were no long-term complications.
Conclusions
The symptoms and surgical findings presented in this cohort for young-onset TN are similar to those reported in elderly adults. MVD appears to be a safe and effective treatment for young patients with TN.
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