Semiconducting Polycomplex Nanoparticles for Photothermal Ferrotherapy of Cancer

This study reports the development of iron‐chelated semiconducting polycomplex nanoparticles (SPFeN) for photoacoustic (PA) imaging‐guided photothermal ferrotherapy of cancer. The hybrid polymeric nanoagent comprises a ferroptosis initiator (Fe³⁺) and an amphiphilic semiconducting polycomplex (SP_C) serving as both the photothermal nanotransducer and iron ion chelator. By virtue of poly(ethylene glycol) (PEG) grafting and its small size, SPFeN accumulates in the tumor of living mice after systemic administration, which can be monitored by PA imaging. In the acidic tumor microenvironment, SPFeN generates hydroxyl radicals, leading to ferroptosis; meanwhile, under NIR laser irradiation, it generates localized heat to not only accelerate the Fenton reaction but also implement photothermal therapy. Such a combined photothermal ferrotherapeutic effect of SPFeN leads to minimized dosage of iron compared to previous studies and effectively inhibits the tumor growth in living mice, which is not possible for the controls.     

5-氟尿嘧啶的三元环类化合物的缀合物的合成及其抗肿瘤活性

基于具有三元环状结构的化合物的广泛生理活性和氟尿嘧啶的抗癌作用机制,本文设计、合成并表征了一系列新型5-氟尿嘧啶（5-FU）的三元碳环缀合物及三元氧杂环缀合物。并对5-FU 的N-1和N-3位的选择性烷基化方法进行了系统研究,发现苄氧甲酰氧甲基保护基具有稳定性高、有效保护性好、制备方便、易于脱除等特点,适宜于在本类反应中应用。测试了所合成的新型5-FU三元环缀合物的体外抗肿瘤活性,化合物7、8、12、13显示了对人食管癌细胞Ec9706不同程度的抑制活性。     

LC–MS Method for the Quantification of Clonazepam in Rat Plasma

A sensitive and specific high-performance liquid chromatography–tandem mass spectrometry method has been developed and validated for the determination of clonazepam in rat plasma. Clonazepam and internal standard diazepam were extracted from plasma samples by a single-step protein precipitation. The chromatographic separation was performed on a Dikma ODS-C18 reversed-phase column at 40 °C. The mobile phase composed of a premix of solvent A (0.1% formic acid–4 mM ammonium acetate–water)–solvent B (acetonitrile) (13:87, v/v) at a flow-rate of 0.7 mL min⁻¹. Positive electrospray ionization was utilized as the ionization source. Clonazepam and the internal standard were determined using multiple reaction monitoring of precursor → product ion transitions at m/z 316.0 → 270.0 and m/z 285.1 → 193.2, respectively. The lower limit of quantification was 0.25 ng mL⁻¹ using 50 μL plasma samples and the linear calibration range was from 0.25 to 128 ng mL⁻¹. The within- and between-batch RSDs were lower than 15% and the relative recoveries of clonazepam ranged from 97.4 to 104.7%. The mean extraction recoveries of clonazepam and IS were 79.7 and 77.6%, respectively. The method has been successfully applied to the pharmacokinetic studies in rat after oral administration of clonazepam.

     

Direct Asymmetric Aldol Reaction Co-catalyzed by Amphiphilic Prolinamide Phenol and Lewis Acidic Metal on Water

An approach based on combinations of various water compatible Lewis acids and lipophilic group containing amphiphilic prolinamide co‐catalysts has been evaluated for the direct asymmetric Aldol reaction. From the broad screening of chloride salts from alkali metal to transition metal, LiCl, ZnCl₂ and SnCl₂ lead to the highest stereoselectivities. The optimized catalytic conditions (10 mol% prolinamide with 10 mol% MCl₂ or 20 mol% LiCl at room temperature on water) gave anti‐products with improved enantioselectivities (up to 99% ee) compared to the moderately stereoselective procedure based on prolinamide activation only.     

Access to Polysulfides through Photocatalyzed Dithiosulfonylation

In this study, we outline a general method for photocatalyzed difunctionalization of alkenes, a diene, alkynes, 1,3-enynes, and [1.1.1]propellane using dithiosulfonate reagents (ArSO₂-SSR) with improved atom economy. Both “ArSO₂-” and “-SSR” on the dithiosulfonate are transferred under mild conditions with broad substrate scope, high stereoselectivity, and complete regioselectivity. Significantly, the resulting dithiosulfonylated styrene is a general and practical nucleophilic disulfuration reagent, reacting with a variety of electrophiles efficiently. Both reactions can be conducted on gram scale, rendering the approach highly valuable.     

Design and synthesis of a tridentate ligand inspired by the phenomenon of self-assembly catalysis and its application in the asymmetric alkynylation of N-(diphenylphosphinoyl) imines

On the basis of the phenomenon of self-assembly catalysis, a tridentate ligand was designed and synthesized in two steps. The application in alkynylation of N-(diphenylphosphinoyl) imines gave the expected products. Aromatic, heteroaromatic N-(diphenylphosphinoyl) imines were employed and gave optically active propargylic amines in good yields (up to 89%) and excellent enantioselectivities (up to 96%) by a simple experimental procedure. The direct use of sulfone amides in the alkynylation of N-(diphenylphosphinoyl) aliphatic imines made this method very attractive.     

新型氮杂大环化合物的研究3: 取代不对称多齿氮 杂大环化合物的合成、表征 与配位性能

合成了四种以Nsp^2和Nsp^3为配位原子的取代不对称多齿氮杂大环化合物,制备了它们与不同金属离子的配合物,通过元素分析和光谱表征,研究了配体的结构与其配位性能的关系。以吡啶环为侧链功能基的配体L^1和L^2可根据其环大小选择性地识别Na^+或K^+离子,与过渡金属离子形成1:1型配合物,而与Hg^2^+,Cd^2^+等离子则形成1:2型配合物。大环配体L^3与Co^2^+和Na^+离子形成的双核配合物中两个冠醚环和一个Na^+离子形成夹心配位结构。L^5环中有两个配位中心,因而可同时与两个Ru^2^+离子配位。L^1和L^2均表现出对不同金属离子良好的液膜传输性能和传输选择性。     

Progress in Visible Light‐Induced Difluroalkylation of Olefins

The incorporation of difluoromethylated (CF₂) moiety into potentially useful parent molecules lead to significant changes in metabolic stability, lipophilicity, and solubility of the molecules. Over the past several years, with the advent of new difluoromethylating reagents, great progress has been made in the development of a protocol for the direct incorporation of the CF₂H group into organic molecules. Among them, difluroalkylation induced by visible light has emerged as an efficient strategy over the past few years. In particular, this protocol provides a more sustainable alternative to other traditional radical‐triggered reactions in terms of environment, energy, step‐economy, health, and safety. The present review mainly focuses on the development of the photocatalytic difluoroalkylation to olefinic moiety using transition‐metal complexes, organic dyes as the photocatalyst; and some organic compounds as a medium of photocatalysis.