Two Different Three-Dimensional Uranium-Containing Polymolybdates Based on Zn(II) for the Heterogeneous Catalytic Construction of C-N Bond.

The introduction of transition metal (TM) ions into polyoxometalates (POMs) cannot only bring about interesting structural diversities but also enable changes in properties. However, TM-containing Silverton-type polyoxomolybdates are still lacking in terms of structural diversity and application development. Herein, two Zn(II)-containing Silverton-type {UMo12O42}-based polyoxomolybdates, H1.89Na4.11(H2O)9Zn[UMo12O42]·4.5H2O (Zn-1) and H1.8Na4.2(H2O)12Zn[UMo12O42] (Zn-2) were hydrothermally synthesized, demonstrating a practical strategy to assembly of TM-containing Silverton-type POMs. Zn-1 is proven to be an excellent and recyclable heterogeneous catalyst in cross-dehydrogenation coupling of 1,4-naphthoquinones with amines reactions, and a series of 2-amino-1,4-naphthoquinones with potential medicinal value have been constructed.

A Meso Butterfly-Like Ce(III)-Containing Antimonotungstate with Catalytic Activity for Synthesizing Isoindolinones.

A unique meso Ce(III)-containing antimonotungstate, {Na(OAc)(H2O)2[Ce4(tar)(Htar)2(Sb2W21O72)2(H2O)7]}244- (Ce4tar3; H4tar = tartaric acid), consisting of two enantiomeric parts with a butterfly-like configuration, was successfully synthesized by a one-pot in situ method and characterized. The coordination of d- or l-tar ligands induced the formation of Dawson-like {Ce2Sb2W21} with right or left configurations, thereby determining the d/l configurations of {Na(OAc)(H2O)2[Ce4(tar)(Htar)2(Sb2W21O72)2(H2O)7]}22-. Carboxyl groups link these two enantiomeric parts with Ce(III) ions from each other around the symmetric center of the P1̅ space group. The three types of tar ligands exhibit distinct coordination modes, and all coordinate with at least one W(VI) atom using one carboxylate oxygen atom and one α-OH. Ce4tar3 represents the largest case among those meso-dl-tar-functionalized polyoxometalates. Furthermore, Ce4tar3 exhibits excellent catalytic activity for synthesizing isoindolinones via the three-component reaction of 2-acetylbenzoic acids, amines, and phosphine oxides.

An Unusual Crystalline Porous Framework Constructed from Multitypes of Cages with Proton Conduction Property and Heterogeneous Catalytic Activity for Pyrazole Synthesis.

An unusual crystalline porous framework constructed from four types of cages, including all-inorganic Keggin-type polyoxometalate (POM) cages [H3W12O40]5-, organic hexamethylenetetramine (Hmt) cages, nanosized silver-Hmt coordination cages, and giant POM-silver-Hmt cages, was hydrothermally synthesized and structurally characterized. The framework features a highly symmetrical structure with one-dimensional nanoscale channels and holds good thermal/solvent stability, which endow it with proton conduction properties and heterogeneous catalytic activity for pyrazole. This paper not only contributes to broadening the structural diversity of cage-based crystalline porous framework materials but also sheds new light on the design of new functional framework materials.

The Assembly of Cerium(III)-Containing Silicotungstate with Lewis Acid-Base Sites Enables the Selective C3-Alkenylation of Oxindole.

A cerium(III)-containing silicotungstate, [H2N(CH3)2]10NaK[KCe(SiW11O39)2(H2O)]·18.5H2O (CeSiW), was successfully synthesized and characterized. Structure analysis reveals that CeSiW is composed of two {SiW11O39} units connected by one cerium(III) cation to form a typical 1:2 sandwich structure, which is further expanding into a 1D chain linked by K+ ions. The oxygen-enriched surfaces of {SiW11O39} units and open cerium sites provide abundant Lewis base and acid sites in CeSiW. As a result, CeSiW efficiently catalyzed the C3-alkenylation of oxindoles with aldehydes through the simultaneous activation of both reaction substrates on its crystal framework. Various 3-benzylidene-oxindoles are synthesized with excellent yields and high E-selectivity under solvent-free conditions.

Three Polyoxometalate-Based Ag-Organic Compounds as Heterogeneous Catalysts for the Synthesis of Benzimidazoles.

Three new POM-based compounds, with formulae [Na0.63Ag3(Htba)2.37(tba)0.63(H2O)2(PMo12O40)]·4H2O (Ag3PMo), [Ag4(Htba)4(H2O)2(PMo12O40)](NO3)·H2O (Ag4PMo), and [Ag3(Htba)2(tba)(PW12O40)0.5](NO3)0.5·13H2O (Ag3PW), were prepared with a 3-(4H-1,2,4-triazol-4-yl)benzoic acid (Htba) ligand, Keggin-type anions ([PMo12O40]3-/[PW12O40]3-), and a silver ion (Ag+). The structural features of these compounds are particularly different from the multinuclear subunits, which are [Ag3(tba)3] clusters in Ag3PMo, [Ag4(tba)3] chains in Ag4PMo, and [Ag3(tba)3]2 clusters in Ag3PW, connected by multidonor atom tba ligands and Ag+ ions. Meanwhile, in these compounds, polyanions act as polydentate ligands to link adjacent Ag-tba metal-organic units and expand their spatial dimensions. These compounds, as heterogeneous catalysts, exhibit high stability and excellent catalytic activity to construct benzimidazoles. Ag3PMo could efficiently catalyze the condensation of benzene-1,2-diamines and benzaldehydes and produce benzimidazoles in good yields. In addition, Ag3PMo could be reused up to 7 times and was suitable for gram-scale reactions.

Two-Fold Interpenetrated Binuclear Nickel Metal-Organic Framework as a Heterogeneous Catalyst for N-Heterocycle Synthesis.

A binuclear Ni(II)-based metal-organic framework {[Ni2(btb)1.333(H2O)3.578(py)1.422]·(DMF)(H2O)3.25}n (Nibtb) was solvothermally synthesized (H3btb = 1,3,5-tri(4-carboxylphenyl)benzene, py = pyridine, DMF = N,N-dimethylformamide). Nibtb shows a rare 2-fold interpenetrating (3,4)-connected 3D network with a point symbol of (83)4(86)3 based on binuclear Ni(II) clusters. Nibtb as a heterogeneous catalyst combines the high stability of MOFs and excellent catalytic activity of nickel, which exhibits excellent catalytic activity for the synthesis of benzimidazoles and pyrazoles under mild conditions. Moreover, the catalyst can be easily separated and reused for seven successive cycles and maintains high catalytic activity.

[Application of high-speed counter current chromatography in extraction and separation of alkaloids in natural products].

Alkaloids, widespread in plants, have a series of pharmacological activities and have been widely used to treat various diseases. Because alkaloids are usually presented in multicomponent mixtures and are deeply low in content, they are very difficult to extract and separate by traditional methods. High-speed counter current chromatography(HSCCC) is a kind of liquid-liquid chromatography without solid support phase, which has the advantages of large injection volume, low cost, and no irreversible adsorption. Compared with the traditional methods of extraction and separation of alkaloids, HSCCC can ensure the separation of many different alkaloids at one time, with a high recovery and large amount. In this paper, the advantages and disadvantages of HSCCC compared with traditional separation methods were discussed and the solvent system and elution mode of HSCCC used to separate alkaloids in recent years were summarized by referring to the relevant literature to provide some references for the separation of alkaloids by HSCCC.

IRF7 suppresses hematopoietic regeneration under stress via CXCR4.

Hematopoietic stem cells (HSCs) maintain quiescence under steady state; however, they are compelled to proliferate and expand to replenish the blood system under stress. The molecular basis underlying stress hematopoiesis remains to be fully understood. In this study, we reported that IRF7 represents an important regulator of stress hematopoiesis. Interferon regulatory factor 7 (IRF7) was dispensable for normal hematopoiesis, whereas its deficiency significantly enhanced hematopoietic stem and progenitor cells (HSPCs) regeneration and improved long-term repopulation of HSCs under stress. Mechanistic studies showed that CXCR4 was identified as a downstream target of IRF7. Overexpression of CXCR4 abrogated the enhanced proliferation and regeneration of IRF7-deficient HSPCs under stress. Similar results were obtained in HSCs from human umbilical cord blood. These observations demonstrated that IRF7 plays an important role in hematopoietic regeneration under stress.

Regioselective Synthetic Approach to Higher Alkenes from Lower Alkenes with Sulfoxides in the Fe3+/H2O2 System via Direct Alkylation or Arylation of the Csp2-H Bond on the C═C Bond of Alkenes.

The regioselective synthetic approach to higher alkenes from lower alkenes by using sulfoxides as alkyl or aryl reagents in the Fe3+/H2O2 system has been developed. This reaction realized direct alkylation or arylation of alkenes. In this reaction, sulfoxides afforded one Csp3 or Csp2 atom to the C═C bond of alkenes; one new Csp2-Csp3 bond or Csp2-Csp2 bond was formed. Nearly 40 products including di-, tri-, and tetra-substituted products were regioselectively synthesized. Both aliphatic and aromatic alkenes could participate in this reaction. Moreover, not only dimethyl sulfoxide but also three other sulfoxides can be applied to this reaction, including diethyl, dibenzyl, and diphenyl sulfoxide. The mechanism studies showed that this reaction may experience a coupling process via radical addition-elimination and the Fe3+/H2O2 system made the sulfoxides offered one alkyl or aryl radical to the C═C bond of alkenes.

Melatonin mediates reactive oxygen species homeostasis via SlCV to regulate leaf senescence in tomato plants.

Melatonin (MT) functions in removing reactive oxygen species (ROS) and delaying plant senescence, thereby acting as an antioxidant; however, the molecular mechanism underlying the specific action of MT is unclear. Herein, we used the mutant plants carrying the MT decomposition gene melatonin 3-hydroxylase (M3H) in tomato to elucidate the specific mechanism of action of MT. SlM3H-OE accelerated senescence by decreasing the content of endogenous MT in plants. SlM3H is a senescence-related gene that positively regulates aging. MT inhibited the expression of the senescence-related gene SlCV to scavenge ROS, induced stable chloroplast structure, and delayed leaf senescence. Simultaneously, MT weakened the interaction between SlCV and SlPsbO/SlCAT3, reduced ROS production in photosystem II, and promoted ROS elimination. In conclusion, MT regulates ROS homeostasis and delays leaf aging in tomato plants through SlCV expression modulation.

Copper-Containing Polyoxometalate-Based Metal-Organic Frameworks as Heterogeneous Catalysts for the Synthesis of N-Heterocycles.

Three new polyoxometalate-based metal-organic frameworks (POMOFs) [Cu4(µ3-OH)2(tba)3(H2O)5(SiW12O40)0.5](H2SiW12O40)0.5·2.5H2O (CuSiW), [Cu3(µ3-OH)(tba)3(Htba)(H2O)2(HPMo12O40)]·7H2O (CuPMo), and [Cu4(µ3-OH)2(tba)3(H2O)3(PW12O40)0.5]2(PW12O40)·0.5H2O (CuPW) were constructed using multinuclear copper clusters, 3-(4H-1,2,4-triazol-4-yl)benzoic acid (Htba), and Keggin polyoxometalates (POMs). Different POMs regulate the formation of different multinuclear copper clusters ("boat" tetranuclear clusters in CuSiW, trinuclear clusters in CuPMo, and "chair" tetranuclear clusters in CuPW) and different topological structures of CuSiW, CuPMo, and CuPW (3-connected two-dimensional (2D) network for CuSiW, 4-connected 2D network for CuPMo, and (4,6)-connected three-dimensional network for CuPW). CuSiW, CuPMo, and CuPW as heterogeneous catalysts combine the high stability of MOFs in polar solvents and excellent catalytic activity of POMs and could be used for the synthesis of nitrogen-heterocycle compounds. The condensation cyclization reactions of 2-aminophenols/benzenesulfonyl hydrazines with 1,3-diketones produce benzoazoles and pyrazoles in good to excellent yields under the catalysis of CuPMo. Moreover, the catalyst could be reused at least for 7 runs, and this protocol was suitable for gram-scale reactions.

Self-Assembly of a U(VI)-Containing Polytungstate Tetramer with Lewis Acid-Base Catalytic Activity for a Dehydration Condensation Reaction.

A novel U(VI)-containing polytungstate (U-POW) tetramer, {K1.37Na26.63[K2(UO2)4Cl0.5(OH)5.5(γ-SiW10O36)4]}·ca66H2O (U4), was synthesized using the Keggin-type precursor [γ-SiW10O36]8- and UO2(NO3)2. U4 was further characterized by single-crystal X-ray diffraction, FT-IR, Raman spectroscopy, solid-state diffuse reflection spectroscopy, ICP-OES, ESI-MS, TGA, and PXRD. The central {K2(UO2)4Cl0.5(OH)5.5} chromophore was constructed dexterously from four uranyl, four halves of K ions, 5.5 bridging µ2-OH, and disordered Cl ions, and was further stabilized by four {γ-SiW10} moieties to construct the tetramer [K2(UO2)4Cl0.5(OH)5.5(γ-SiW10O36)4]28-. Notably, U4 could work as an effective bifunctional Lewis acid-base catalyst for the synthesis of pyrazoles via the condensation of hydrazines with 1,3-diketones under mild conditions, which is attributed to the synergetic effect of the Lewis acidity of U(VI) and the Lewis basicity of {γ-SiW10}.

Lignans and a neolignan from an aqueous extract of Isatis indigotica roots.

Four new lignans (1-4) and one new neolignan (5), along with two known lignan derivatives (6 and 7), were isolated from an aqueous extract of the Isatis indigotica root (ban lan gen). Their structures were determined by spectroscopic data analysis, chemical method, and theoretical calculation, for which 1 was proved by single-crystal X-ray diffraction. Compound 2 exhibited antiviral activity against influenza virus A/Hanfang/359/95 (H3N2) with an IC50 value of 11.1 µM and a selective index (SI) > 9, while 1 and 5 are the first examples of sulfonated lignan and neolignan from nature.

Natural bioactive compounds from marine fungi (2017-2020).

Secondary metabolites generated by marine fungi have relatively small molecular weights and excellent activities and have become an important source for developing drug lead compounds. The review summarizes the structures of novel small-molecule compounds derived from marine fungi in recent years; introduces representative monomers in antimicrobial, antitumor, anti-viral, and anti-neuritis aspects; and discusses their biological activities and molecular mechanisms. This review will act as a guide for further discovering marine-derived drugs with novel chemical structures and specific targeting mechanisms.

High Throughput Isolation and Data Independent Acquisition Mass Spectrometry (DIA-MS) of Urinary Extracellular Vesicles to Improve Prostate Cancer Diagnosis.

Proteomic profiling of extracellular vesicles (EVs) represents a promising approach for early detection and therapeutic monitoring of diseases such as cancer. The focus of this study was to apply robust EV isolation and subsequent data-independent acquisition mass spectrometry (DIA-MS) for urinary EV proteomics of prostate cancer and prostate inflammation patients. Urinary EVs were isolated by functionalized magnetic beads through chemical affinity on an automatic station, and EV proteins were analyzed by integrating three library-base analyses (Direct-DIA, GPF-DIA, and Fractionated DDA-base DIA) to improve the coverage and quantitation. We assessed the levels of urinary EV-associated proteins based on 40 samples consisting of 20 cases and 20 controls, where 18 EV proteins were identified to be differentiated in prostate cancer outcome, of which three (i.e., SERPINA3, LRG1, and SCGB3A1) were shown to be consistently upregulated. We also observed 6 out of the 18 (33%) EV proteins that had been developed as drug targets, while some of them showed protein-protein interactions. Moreover, the potential mechanistic pathways of 18 significantly different EV proteins were enriched in metabolic, immune, and inflammatory activities. These results showed consistency in an independent cohort with 20 participants. Using a random forest algorithm for classification assessment, including the identified EV proteins, we found that SERPINA3, LRG1, or SCGB3A1 add predictable value in addition to age, prostate size, body mass index (BMI), and prostate-specific antigen (PSA). In summary, the current study demonstrates a translational workflow to identify EV proteins as molecular markers to improve the clinical diagnosis of prostate cancer.

[Risk factors for acute kidney injury after hematopoietic stem cell transplantation in children: a retrospective study]. / å„¿ç«¥é€ è¡€å¹²ç»†èƒžç§»æ¤åŽæ€¥æ€§è‚¾æŸä¼¤ç›¸å ³å±é™©å› ç´ çš„å›žé¡¾æ€§ç ”ç©¶.

OBJECTIVES: To investigate the risk factors for acute kidney injury (AKI) after hematopoietic stem cell transplantation (HSCT) in children. METHODS: A retrospective analysis was performed on the medical data of 111 children who underwent HSCT from January 2018 to January 2020. A multivariate logistic regression analysis was used to identify the risk factors for AKI. The Kaplan-Meier survival analysis was used to compare the prognosis in children with different grades of AKI. RESULTS: Graft-versus-host disease (grade Ⅱ-Ⅳ) (OR=4.406, 95%CI: 1.501-12.933, P=0.007), hepatic veno-occlusive disease (OR=4.190, 95%CI: 1.191-14.740, P=0.026), and thrombotic microangiopathy (OR=10.441, 95%CI: 1.148-94.995, P=0.037) were closely associated with the development of AKI after HSCT. The children with stage Ⅲ AKI had a lower 1-year survival rate than those without AKI or with stage Ⅰ AKI or stage Ⅱ AKI (28.6%±12.1% vs 82.8%±5.2%/81.7%±7.4%/68.8%±11.6%; P<0.05). CONCLUSIONS: Children with stage Ⅲ AKI after HSCT have a higher mortality rate. Graft-versus-host disease, hepatic veno-occlusive disease, and thrombotic microangiopathy are closely associated with the development of AKI after HSCT.

Comparative efficacy and safety of first-line treatments for advanced non-small cell lung cancer with ALK-rearranged: a meta-analysis of clinical trials.

BACKGROUND: Whereas there are many pharmacological interventions prescribed for patients with advanced anaplastic lymphoma kinase (ALK)- rearranged non-small cell lung cancer (NSCLC), comparative data between novel generation ALK-tyrosine kinase inhibitors (TKIs) remain scant. Here, we indirectly compared the efficacy and safety of first-line systemic therapeutic options used for the treatment of ALK-rearranged NSCLC. METHODS: We included all phase 2 and 3 randomised controlled trials (RCTs) comparing any two or three treatment options. Eligible studies reported at least one of the following outcomes: progression free survival (PFS), overall survival (OS), objective response rate (ORR), or adverse events of grade 3 or higher (Grade ≥ 3 AEs). Subgroup analysis was conducted according to central nervous system (CNS) metastases. RESULTS: A total of 9 RCTs consisting of 2484 patients with 8 treatment options were included in the systematic review. Our analysis showed that alectinib (300 mg and 600 mg), brigatinib, lorlatinib and ensartinib yielded the most favorable PFS. Whereas there was no significant OS or ORR difference among the ALK-TKIs. According to Bayesian ranking profiles, lorlatinib, alectinib 600 mg and alectinib 300 mg had the best PFS (63.7%), OS (35.9%) and ORR (37%), respectively. On the other hand, ceritinib showed the highest rate of severe adverse events (60%). CONCLUSION: Our analysis indicated that alectinib and lorlatinib might be associated with the best therapeutic efficacy in first-line treatment for major population of advanced NSCLC patients with ALK-rearrangement. However, since there is little comparative evidence on the treatment options, there is need for relative trials to fully determine the best treatment options as well as the rapidly evolving treatment landscape.

Alkyl lithium-catalyzed benzylic C-H bond addition of alkyl pyridines to α-alkenes.

Brønsted base catalyzed C-C bond formation reactions have been extensively utilized as reliable, efficient, and atom economical methods in organic synthesis. However, the electrophiles were mostly limited to polar ones such as imines, carbonyl compounds, α,ß-unsaturated compounds, styrenes and conjugated dienes. The use of α-alkenes as electrophiles in the C-C bond formation reactions always needs transition metal catalysts. Herein, we reported an alkyl lithium-catalyzed benzylic C-H bond addition of alkyl pyridines to α-alkenes. The alkyl lithium catalyst displayed quite different selectivity from those of transition metal catalysts.

Copper-catalyzed aerobic oxidative C-C bond cleavage of simple ketones for the synthesis of amides.

A Cu-catalyzed oxidative amidation of simple ketones with amines via carbon-carbon (C-C) bond cleavage has been developed. A number of aryl and alkyl ketones could be easily converted to amides using cheap copper salt as the catalyst and O2 as the oxidant with a wide range of amines, including primary and secondary amines. This method shows a notable advantage of the broad scope for the substrate, thus providing a practical approach to amides. A plausible mechanism is proposed based on the preliminary experiments.

Potassium Amide-Catalyzed Benzylic C-H Bond Addition of Alkylpyridines to Styrenes.

The benzylic functionalization of alkylpyridines is an important pathway for pyridine derivatives synthesis. The reaction partners, however, were mostly limited to highly reactive polar electrophiles. Herein, we report a potassium amide-catalyzed selective benzylic C-H bond addition of alkylpyridines to styrenes. Potassium bis(trimethylsilyl)amide (KHMDS), a readily available Brønsted base, showed excellent catalytic activity and chemoselectivity. A series of alkylpyridine derivatives, including benzylic quaternary carbon substituted pyridines, were obtained in good to high yield. Preliminary mechanistic studies revealed that the deprotonation equilibrium is probably responsible for the excellent selectivity.