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Using a quinoline substituted Qsal ligand, Hqsal-5-Br q (Hqsal-5-Br q = N-(5-bromo-8-quinolyl)salicylaldimine), four Fe III complexes, [Fe(qsal-5-Br q ) 2 ]A·CH 3 OH (Y = NO 3 - ( 1 NO3 ), BF 4 - ( 2 BF4 ), PF 6 - ( 3 PF6 ), OTf - ( 4 OTf ), were prepared and characterized. Structure analysis revealed that complex 2 BF4 contained two species ( 2 BF4 ( P 1 ̅) and 2 BF4 ( C 2/ c )). In these compounds except 3 PF6 , the [Fe(qsal-5-Br q ) 2 ] + cations form 1D chains through π-π interactions and other weak interactions. Adjacent chains are connected to form the 2D "Chain Layer" structures and 3D structures through various supramolecular interactions. For 3 PF6 , a "Dimer Chain" structure is formed from the loosely connected dimers. Magnetic studies revealed that compounds 1 NO3 and 2 BF4 ( P 1 ̅) displayed abrupt hysteretic SCO with the transition temperature T 1/2 ↓ = 235 K, T 1/2 ↑ = 240 K for 1 NO3 and T 1/2 ↓ = 230 K, T 1/2 ↑ = 235 K for 2 BF4 ( P 1̅ ), while compounds 3 PF6 and 4 OTf are in the HS state. Desolvation of the complexes significantly modifies their SCO properties: the desolvated 1 NO3 and 2 BF4 show a gradual SCO, desolvated 3 PF6 undergoes a two-step SCO, and desolvated 4 OTf exhibits a hysteretic transition. Overall, this work reported the Fe III -SCO complexes of the quinoline-substituted Hqsal ligand and highlighted the potential of these ligands for the development of interesting Fe III -SCO materials.

Three new cyano-bridged Fe II -Mo III complexes assembled from the [Mo III (CN) 7 ] 4- unit, Fe II ions, and three pentadentate N 3 O 2 ligands, namely {[Fe 2 H 3 (dapab) 2 ][Mo(CN) 6 ]} n ·2H 2 O·3.5MeCN ( 1 ), [Fe(H 2 dapb)(H 2 O)][Fe(Hdapb)(H 2 O)][Mo(CN) 6 ]·4H 2 O·3MeCN ( 2 ), and [Fe(H 2 dapba)(H 2 O)] 2 [Mo(CN) 7 ]·6H 2 O ( 3 ) (H 2 dapab = 2,6-diacetylpyridine bis(2-aminobenzoylhydrazone), H 2 dapb = 2,6-diacetylpyridine bis(benzoylhydrazone), H 2 dapba = 2,6-diacetylpyridine bis(4-aminobenzoylhydrazone)), have been synthesized and characterized. Single-crystal structure analyses suggest that complex 1 contains a one-dimensional (1D) chain structure where two Fe II ions are bridged by the in situ generated [Mo III (CN) 6 ] 3- unit through two trans -cyanide groups into trinuclear Fe 2 II Mo III clusters that are further linked by the amino of the ligand into an infinite chain. Complexes 2 and 3 are cyano-bridged Fe 2 II Mo III trinuclear clusters with two Fe II ions connected by the [Mo III (CN) 6 ] 3- and [Mo III (CN) 7 ] 4- units, respectively. Direct current magnetic studies confirmed the ferromagnetic interactions between the cyano-bridged Fe II and Mo III centers and significant easy-axis magnetic anisotropy for all three complexes. Furthermore, complexes 1-3 exhibit slow magnetic relaxation under a zero dc field, with relaxation barriers of 42.3, 21.6, and 14.4 K, respectively, making them the first examples of cyano-bridged Fe II -Mo III single-molecule magnets.

The combination of photo and copper catalysts has emerged as a novel paradigm in organic catalysis, which provides access to the acceleration of chemical synthesis. Herein, we describe an aminoalkylation of amino-dependent olefins with maleimides through a cooperative photo/copper catalytic system. In this report, the strategy allows the generation of a broad complex of functionalized nitrogenous molecules including oxazolidinones, 2-pyrrolidones, imidazolidinones, thiazolidinones, pyridines, and piperidines in the absence of an external photosensitizer and base. The approach is achieved through a photoinduced Cu(I)/Cu(II)/Cu(III) complex species of nitrogen nucleophiles, intermolecular radical addition, and hydrogen atom transfer (HAT) processes. The plausible mechanism is investigated by a series of control experiments and theoretical tests, including radical scavenging experiments, deuterium labeling experiments, ultraviolet-visible absorption, and cyclic voltammetry (CV) tests.

Four iron(III) complexes, [Fe(qsal-4-F) 2 ]Y·sol (Hqsal-4-F = 4-fluoro- N -(8-quinolyl)salicylaldimine; Y = NO 3 - , sol = 0.91MeOH·0.57H 2 O ( 1 NO3 ); Y = PF 6 - ( 2 PF6 ); Y = BF 4 - ( 3 BF4 ); Y = OTf - , sol =1.5MeOH ( 4 OTf )), with a new 4-position substituted qsal type ligand Hqsal-4-F have been synthesized and structurally and magnetically characterized. Complexes 1 NO3 - 3 BF4 consist of 1D chains formed by the [Fe(qsal-4-F) 2 ] + cations connected by π-π and C-H···O interactions, which are further linked by more weak interactions to form 2D layers and 3D networks. On the other hand, complex 4 OTf has a structure of nearly isolated 1D column where the [Fe(qsal-4-F) 2 ] + cations are connected by π-π, C-H···π, and C-F···π interactions. Magnetic studies revealed the occurrence of two-step symmetry-breaking SCO in 1 NO3 and two-step gradual SCO in 2 PF6 . Complex 3 BF4 undergoes a gradual SCO, whereas 4 OTf remains almost high-spin. The smaller anions tend to stabilize the low-spin state, while larger anions tend to stabilize the high-spin state. In addition, the intermediate spin state of 1 NO3 could be thermally trapped by quenching from the high temperature, thereby kinetically suppressing the spin transition to the full low-spin state. This work represents a good example that the position of the substituent and the anions plays critical roles in the preparation of SCO materials with tunable properties.

Examples on the real-world field application of Raman spectroscopy with systematic analysis of the intensity variation of D and G bands corresponding to the change of excitation laser energy to characterize and compare coke species from various industrial processes are presented. The findings indicate the different degree of sp 2 and sp 3 hybridized bonding structures of amorphous carbon collected from different industrial processes as well as heavy carbonaceous deposits generated by industrial catalysts. This spectroscopic methodology is practical and highly beneficial in identifying coke formation mechanisms in industrial processes, as well as supporting design strategies to abate the undesired coke formation on industrial catalysts., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Photothermal therapy (PTT) as a noninvasive and effective thermal therapeutic approach has attracted tremendously increasing interest because it can effectively eliminate the primary tumor and generate tumor-associated antigens, which could elicit antitumor immune responses. Herein, we report on the rational design and fabrication of copper sulfide (CuS)-based nanoplatform for cancer photothermal immunotherapy. The as-prepared core-shell CuS@mSiO 2 -PFP-PEG (CPPs) nanocomposites possess high biocompatibility, photoacoustic (PA)/ultrasound (US) imaging, and strong PTT effect upon 808 nm laser irradiation, indicating that the nanocomposites have a promising application in diagnosis and treatment of breast cancer with molecular classification. Importantly, we also elucidated that the CPP-triggered PTT in combination with anti -PD-1 checkpoint blockade therapy can not only obliterate primary tumor but also inhibit metastatic tumor in tumor-bearing mice. We believe that the CPPs have a good probability to serve as a useful nanoplatform for PTT, and this approach may provide a promising strategy for tumor-therapeutic modality with immunotherapy.

A selective catalytic system for the dehydrogenation of primary alcohols to carboxylic acids using a facial ruthenium complex generated in situ from the [Ru(COD)Cl 2 ] n and a hybrid N-heterocyclic carbene (NHC)-phosphine-phosphine ligand ( CPP ) has been first reported. The facial coordination model was unveiled by NMR analysis of the reaction mixture. Such a fac -ruthenium catalyst system exhibited high catalytic activity and stability, and a high turnover number of 20 000 could be achieved with catalyst loading as low as 0.002 mol %. The exceedingly high catalyst stability was tentatively attributed to both the anchoring role of NHC and the hemi-lability of phosphines. The catalytic system also features a wide substrate scope. In particular, the facial coordination of CPP ligands was found to be beneficial for sterically hindered alcohols, and ortho-substituted benzylic alcohols and bulky adamantanyl methanol as well as cholesterol were all found to be viable dehydrogenation substrates.

One unusual resveratrol tetramer, paeonilactiflorol (1), and 14 known compounds (2-15) were isolated from peony seeds ( Paeonia lactiflora) under the guidance of bioassay. Paeonilactiflorol (1) was determined by extensive HRESIMS, UV, IR, 1D and 2D NMR spectroscopic analyses. Most of the stilbenes showed obvious inhibition on PTP1B and α-glucosidase, superior to the monoterpene glycosides. Especially, the stilbene tetramer (1) and trimer (8) exhibited high activity inhibiting both PTP1B with IC 50 values of 27.23 and 27.81 μM and α-glucosidase with IC 50 values of 13.57 and 14.39 μM. Two trans-dimers (4 and 5) also showed dipeptidyl peptidase-4 (DPPIV) inhibitory activity (55.35% and 61.26%, 500 μM) in addition to PTP1B and α-glucosidase. Enzyme kinetic study indicated that the types of inhibition on PTP1B were noncompetitive for 3 and 5 and mixed for 8 and 10. Quantitative analysis suggested that the stilbene trimers 8 (23.17 ± 0.36 mg/g) and 10 (15.24 ± 0.25 mg/g) were the main contents in peony seeds and should be responsible for the antidiabetic effects. This investigation supports the therapeutic potential of peony seeds in the treatment of diabetes with stilbenes as the active constituents.

CRISPR systems, such as CRISPR-Cas9 and CRISPR-Cpf1, have been successfully used for genome editing in a variety of organisms. Although the technique of CRISPR-Cpf1 has been applied in cyanobacteria recently, its use was limited without exploiting the full potential of such a powerful genetic system. Using the cyanobacterium Anabaena PCC 7120 as a model strain, we improved the tools and designed genetic strategies based on CRISPR-Cpf1, which enabled us to realize genetic experiments that have been so far difficult to do in cyanobacteria. The development includes: (1) a "two-spacers" strategy for single genomic modification, with a success rate close to 100%; (2) rapid multiple genome editing using editing plasmids with different resistance markers; (3) using sacB, a counter-selection marker conferring sucrose sensitivity, to enable the active loss of the editing plasmids and facilitate multiple rounds of genetic modification or phenotypic analysis; (4) manipulation of essential genes by the creation of conditional mutants, using as example, polA encoding the DNA polymerase I essential for DNA replication and repair; (5) large DNA fragment deletion, up to 118 kb, from the Anabaena chromosome, corresponding to the largest bacterial chromosomal region removed with CRISPR systems so far. The genome editing vectors and the strategies developed here will expand our ability to study and engineer cyanobacteria, which are extensively used for fundamental studies, biotechnological applications including biofuel production, and synthetic biology research. The vectors developed here have a broad host range, and could be readily used for genetic modification in other microorganisms.

A novel optical nanoprobe based on silicon quantum dots (SiQDs) has been assembled through a one-pot low-temperature (40 °C) treatment by using 3-(aminopropyl)trimethoxysilane (APTMS) and ascorbic acid (AA) as two precursors. The water-soluble SiQDs demonstrate intense green luminescence in aqueous environment and the excitation-dependent feature has been explored. Meanwhile, the incorporation of salicylaldehyde (SA) serves to suppress the emission of SiQDs effectively via nucleophilic reaction and an "on-off" change is observed. Furthermore, the addition of Zn 2+ can lead to evolution of emission peaks, and the green band at 500 nm gradually shifts toward the blue side at 455 nm. The corresponding ratiometric signal changes ( I 455 / I 500 ) can accurately determine the Zn 2+ concentration and the limit of detection is calculated to be 0.17 μM in the linear range between 1 and 100 μM. In this research, a molecular logic gate (AND) system has been well established by using SA and Zn 2+ as two inputs. The fluorescence emission changes based on SiQDs will shed new light on the development of functional sensors at the nanoscale level.

Sarcodonin G, one of the cyathane diterpenoids isolated from the mushroom Sarcodon scabrosus, possesses pronounced neurotrophic activity but ambiguous mechanical understanding. In this work, sarcodonin G was chosen as a lead compound to prepare a series of 19- O-benzoyl derivatives by semisynthesis and their neuritogenic activities were evaluated. 6 and 15 (10 μM) were investigated with opposite effects in PC12 cells. 6 exhibited a superior activity to sarcodonin G by promoting NGF-induced neurite outgrowth, while 15 showed an inhibitory effect. Supportingly, 6 and 15 (20 μM) significantly induced and suppressed neurite extension in primary cultured rat cortical neurons, respectively. In mechanism, the two derivatives were revealed to influence NGF-induced neurite outgrowth in PC12 cells through the regulation of PKC-dependent and -independent ERK/CREB signaling as well as the upstream TrkA receptor phosphorylation. Furthermore, a possible pattern of interaction among NGF, 6/15 and TrkA was presented using molecular simulations. It revealed that 6/15 may contribute to the stabilization of the NGF-TrkAd5 complex by establishing several hydrophobic and hydrogen-bond interactions with NGF and TrkA, respectively. Taken together, 6 and 15 modulate PKC-dependent and -independent ERK/CREB signaling pathways possibly by influencing the binding affinity of NGF to the receptor TrkA, and finally regulate neurite outgrowth in PC12 cells.

Upconversion nanoparticles (UCNPs) possess several unique features, but they suffer from surface quenching effects caused by the interaction between the UCNPs and fluorophore. Thus, the use of UCNPs for target-induced emission changes for biosensing and bioimaging has been challenging. In this work, fluorophore and UCNPs are effectively separated by a silica transition layer with a thickness of about 4 nm to diminish the surface quenching effect of the UCNPs, allowing a universal and efficient luminescence resonance energy transfer (LRET) ratiometric upconversion luminescence nanoplatform for biosensing applications. A pH-sensitive fluorescein derivative and Hg(2+)-sensitive rhodamine B were chosen as fluoroionphores to construct the LRET nanoprobes. Both showed satisfactory target-triggered ratiometric upconversion luminescence responses in both solution and live cells, indicating that this strategy may find wide applications in the design of nanoprobes for various biorelated targets.

We report biological evaluation of a novel nanoparticle delivery system based on 1,1,2-triphenyl-2-(p-hydroxyphenyl)-ethene (TPE-OH, compound 1), which has tunable aggregation-induced emission (AIE) characteristics. Compound 1 exhibited no emission in DMSO. In aqueous media, compound 1 aggregated, and luminescence was observed. The novel membrane-cytoplasm-nucleus sequential delivery strategy could induce apoptosis in four different kinds of cancer cells (including three adherent cell lines and one suspension cell line). The nanoparticles remained in the cytoplasm with intense blue emissions, whereas doxorubicin was observed in the nucleus with striking red luminescence. The nanoassembly was internalized in cells through an energy-dependent process. Three sorts of chemical inhibitors were used to clarify the endocytosis mechanism based on the AIE type prodrug. Furthermore, we have developed the first AIE theranostic system where drug targeting and release have been applied in an animal model.

Small GTPases are a family of key signaling molecules that are ubiquitously expressed in various types of cells. Their activity is often analyzed by western blot, which is limited by its multiplexing capability, the quality of isoform-specific antibodies, and the accuracy of quantification. To overcome these issues, a quantitative multiplexed small GTPase activity assay has been developed. Using four different binding domains, this assay allows the binding of up to 12 active small GTPase isoforms simultaneously in a single experiment. To accurately quantify the closely related small GTPase isoforms, a targeted proteomic approach, i.e., selected/multiple reaction monitoring, was developed, and its functionality and reproducibility were validated. This assay was successfully applied to human platelets and revealed time-resolved coactivation of multiple small GTPase isoforms in response to agonists and differential activation of these isoforms in response to inhibitor treatment. This widely applicable approach can be used for signaling pathway studies and inhibitor screening in many cellular systems.

Pyrene excimer possesses a large Stokes shift and long fluorescence lifetime and has been widely applied in developing time-resolved biosensing systems to solve the autofluorescence interference problems in biological samples. However, only a few of pyrene excimer-based small molecular probes have been reported so far. Ratiometric probes, on the other hand, can eliminate interferences from environmental factors such as instrumental efficiency and environmental conditions by a built-in correction of the dual emission bands but are ineffective for endogenous autofluorescence in biosystems. In this work, by combining the advantages of time-resolved fluorescence technique with ratiometric probe, we reported a bispyrene-fluorescein hybrid FRET cassette (PF) as a novel ratiometric time-resolved sensing platform for bioanalytical applications, with pH chosen as a biorelated target. The probe PF showed a fast, highly selective, and reversible ratiometric fluorescence response to pH in a wide range from 3.0 to 10.0 in buffered solution. By employing time-resolved fluorescence technique, the pH-induced fluorescence signal of probe PF can be well-discriminated from biological autofluorescence background, which enables us to detect pH in a range of 4.0-8.0 in cell media within a few seconds. It has also been preliminarily applied for ratiometric quantitative monitoring of pH changes in living cells with satisfying results. Since many fluorescein-based fluorescence probes have been developed, our strategy might find wide applications in design ratiometric time-resolved probes for detection of various biorelated targets.

Five new sesquiterpene polyol esters with a dihydro-β-agarofuran skeleton, designated as wightianines A-E (1-5), besides two known compounds, were isolated from the methanolic extract of the whole plant of the traditional herbal medicine Parnassia wightiana Wall. The structures of the isolated compounds were elucidated on the basis of spectroscopic analyses, including two-dimensional nuclear magnetic resonance techniques (correlation spectroscopy, heteronuclear multiple-quantum coherence, nuclear Overhauser effect spectrometry, and heteronuclear multiple-bond correlation) and electronic circular dichroism studies. The antifungal and insecticidal activities of five compounds were evaluated against several plant pathogenic fungi and armyworm larvae (Mythimna separata Walker). Among the test metabolites, compounds 2 and 7 both exhibited potent antifungal activity against the phytopathogenic fungus Cytospora sp. with minimum inhibitory concentration values of 0.78 μg/mL, which are equal to the two positive controls, hymexazol and carbendazim. However, no insecticidal activity of the test compounds was observed in the present study. Compounds 2 and 7 could be promising leads for developing new fungicides against agriculturally important fungus Cytospora sp.

A 2-oxoglutaric acid (2-OG) probe bearing a methylene group introduced at the C4 position and a vinyl group to replace the carbonyl group at the C2 position elicited characteristic affinity for NtcA, the 2-OG receptor, while maintaining the signaling function of the parent natural metabolite 2-OG. This discovery opens new perspectives in the design, synthesis, and implementation of specific 2-OG analogues as molecular probes for investigating the complex 2-OG signaling pathways.

Fluorescence resonance energy transfer (FRET) strategy has been widely applied in designing ratiometric probes for bioimaging applications. Unfortunately, for FRET systems, sufficiently large spectral overlap is necessary between the donor emission and the acceptor absorption, which would limit the resolution of double-channel images. The through-bond energy transfer (TBET) system does not need spectral overlap between donor and acceptor and could afford large wavelength difference between the two emissions with improved imaging resolution and higher energy transfer efficiency than that of the classical FRET system. It seems to be more favorable for designing ratiometric probes for bioimaging applications. In this paper, we have designed and synthesized a coumarin-rhodamine (CR) TBET system and demonstrated that TBET is a convenient strategy to design an efficient ratiometric fluorescent bioimaging probe for metal ions. Such TBET strategy is also universal, since no spectral overlap between the donor and the acceptor is necessary, and many more dye pairs than that of FRET could be chosen for probe design. As a proof-of-concept, Hg(2+) was chosen as a model metal ion. By combining TBET strategy with dual-switch design, the proposed sensing platform shows two well-separated emission peaks with a wavelength difference of 110 nm, high energy transfer efficiency, and a large signal-to-background ratio, which affords a high sensitivity for the probe with a detection limit of 7 nM for Hg(2+). Moreover, by employing an Hg(2+)-promoted desulfurization reaction as recognition unit, the probe also shows a high selectivity to Hg(2+). All these unique features make it particularly favorable for ratiometric Hg(2+) sensing and bioimaging applications. It has been preliminarily used for a ratiometric image of Hg(2+) in living cells and practical detection of Hg(2+) in river water samples with satisfying results.

2-Difluoromethylene-4-methylenepentanoic acid (DFMPA), a seemingly deviated analog of 2-oxoglutaric acid (2-OG), could surprisingly mimic its signaling function in cyanobacteria. Computer modeling revealed the favorable binding of DFMPA toward the 2-OG receptor, NtcA, via mutual conformational changes, suggesting that structural alteration of 2-OG is tolerated for it to exercise its signaling role. This extremely useful finding could be exploited for the design of affinity probes with which to study new 2-OG receptors in related signaling pathways.

On the basis of the n-acenes (n = 1, 2, 3 and 4), the α-Li@n-acenes and β-Li@n-acenes salts were selected to investigate how increasing the number n of conjugated benzenoid rings affects the linear and nonlinear optical responses. The α-Li@n-acenes and β-Li@n-acenes salts are obtained by a lithium atom substituting the α-H and β-H, respectively. In the present work, both ab initio (HF and MP2) and DFT (B3LYP, BhandHLYP, M05-2X, and CAM-B3LYP) methods are adopted to calculate the polarizability (α(0)) and first hyperpolarizability (β(tot)) of the α-Li@n-acenes and β-Li@n-acenes salts. MP2 results show that the α(0) values of both classes of lithium salts increase with increasing number n of conjugated benzenoid rings. Interestingly, we found that the β(tot) values of α-Li@n-acenes and β-Li@n-acenes salts take on opposite trends: the β(tot) values of α-Li@n-acenes are decreasing slowly (2187 for α-Li@benzene > 1978 for α-Li@naphthalene > 1898 for α-Li@anthrecene > 1830 au for α-Li@tetracene) and inceasing remarkably (2738 for β-Li@naphthalene < 3186 for β-Li@anthrecene < 3314 au for β-Li@tetracene) for β-Li@n-acenes. Furthermore, we found that the β(tot) values (2738-3314 au) of the β-Li@n-acenes are larger than those of the α-Li@n-acenes (1830-2187 au). On the other hand, comparing the results of different methods, the β(tot) values obtained by the M05-2X and CAM-B3LYP methods reproduce the polarizability and first hyperpolarizability of the α-Li@n-acenes and β-Li@n-acenes salts well, which test and verify the results of the MP2 method. Our present work may be beneficial to development of high-performance organic NLO optical materials.

Experiments to probe for protein-protein interactions are the focus of functional proteomic studies, thus proteomic data repositories are increasingly likely to contain a large cross-section of such information. Here, we use the Global Proteome Machine database (GPMDB), which is the largest curated and publicly available proteomic data repository derived from tandem mass spectrometry, to develop an in silico protein interaction analysis tool. Using a human histone protein for method development, we positively identified an interaction partner from each histone protein family that forms the histone octameric complex. Moreover, this method, applied to the α subunits of the human proteasome, identified all of the subunits in the 20S core particle. Furthermore, we applied this approach to human integrin αIIb and integrin β3, a major receptor involved in the activation of platelets. We identified 28 proteins, including a protein network for integrin and platelet activation. In addition, proteins interacting with integrin β1 obtained using this method were validated by comparing them to those identified in a formaldehyde-supported coimmunoprecipitation experiment, protein-protein interaction databases and the literature. Our results demonstrate that in silico protein interaction analysis is a novel tool for identifying known/candidate protein-protein interactions and proteins with shared functions in a protein network.