Proteomic analysis and identification reveal the anti-inflammatory mechanism of clofazimine on lipopolysaccharide-induced acute lung injury in mice.

BACKGROUND AND OBJECTIVE: Acute lung injury (ALI)/ acute respiratory distress syndrome (ARDS) was increasingly recognized as one of the most severe acute hyperimmune response of coronavirus disease 2019 (COVID-19). Clofazimine (CFZ) has attracted attention due to its anti-inflammatory property in immune diseases as well as infectious diseases. However, the role and potential molecular mechanism of CFZ in anti-inflammatory responses remain unclear. METHODS: We analyze the protein expression profiles of CFZ and LPS from Raw264.7 macrophages using quantitative proteomics. Next, the protective effect of CFZ on LPS-induced inflammatory model is assessed, and its underlying mechanism is validated by molecular biology analysis. RESULTS: LC-MS/MS-based shotgun proteomics analysis identified 4746 (LPS) and 4766 (CFZ) proteins with quantitative information. The key proteins and their critical signal transduction pathways including TLR4/NF-κB/HIF-1α signaling was highlighted, which was involved in multiple inflammatory processes. A further analysis of molecular biology revealed that CFZ could significantly inhibit the proliferation of Raw264.7 macrophages, decrease the levels of TNF-α and IL-1ß, alleviate lung histological changes and pulmonary edema, improve the survival rate, and down-regulate TLR4/NF-κB/HIF-1α signaling in LPS model. CONCLUSION: This study can provide significant insight into the proteomics-guided pharmacological mechanism study of CFZ and suggest potential therapeutic strategies for infectious disease.

Probing the Structure-Property Relationships of Na+···Cl-@C50N5H5 under the External Electric Field.

Endohedral open-cage fullerenes are one of the attractive types of fullerenes due to their interesting electronic properties which make it potentially promising for applications in molecular electronics. In this paper, a novel structure of Na+···Cl-@C50N5H5 with Na+ inside the cavity and Cl- at the opening of the open-cage fullerene is designed to explore the chemical bonding and interaction between the open-cage fullerene system C50N5H5 and NaCl salt. Further, the directional migration of Na+ was achieved by applying an external electric field (EEF) along the X-axis. Notably, when the EEF ranges from -85 to -86 × 10-4 au, Na+ sharply approaches Cl- to regain its ionic bonding character. In addition, the Wiberg bond index, electron localization function topological analysis, and interaction energy (Eint) of the structure under the effect of the EEF also experienced a series of interesting changes. We hope that this work will provide a new strategy for the design of innovative materials for molecular electronics.

A Porous Metal-Organic Framework as an Electrochemical Sensing Platform for Highly Selective Adsorption and Detection of Bisphenols.

The design of artificial receptors with a specific recognition function and enhanced selectivity is highly desirable in the electrochemical sensing field, which can be used for detection of environmental pollutants. In this facet, metal-organic frameworks (MOFs) featured adjustable porosities and specific host-guest recognition properties. Especially, the large hydrophobic cavity formed in the porous MOFs may become a potential artificial receptor. We herein designed a new porous MOF [Zn2(L)(IPA)(H2O)]·2DMF·2MeOH·3H2O (Zn-L-IPA) by using a functionalized sulfonylcalix[4]arene (L1) and isophthalic acid (H2IPA) (DMF = N,N'-dimethylformamide). The specific pore size and pore shape of Zn-L-IPA made it efficiently selective for absorption of bisphenol A (BPA), bisphenol F (BPF), and bisphenol S (BPS). Therefore, a rapid, highly selective, and ultrasensitive electrochemical sensing platform Zn-L-IPA@GP/GCE was fabricated by using Zn-L-IPA as a host to recognize and absorb bisphenol guests (GP = graphite powder, GCE = glassy carbon electrode). Most strikingly, the extremely low detection limits were up to 3.46 and 0.17 nM for BPA and BPF, respectively, using the Zn-L-IPA@GP/GCE electrode. Furthermore, the "recognition and adsorption" mechanism was uncovered by density functional theory with the B3LYP function. This work offered a prospective strategy for selective absorption and detection of harmful bisphenols with the MOF-based porous material.

Periodic B- and N-doped phenalenyl π-aggregates: unexpected nonlinear optical properties by tuning pancake π-π bonding.

Phenalenyl (PLY) and its derivatives could form one-dimensional π-aggregates through pancake π-π bonding, which would lead to exotic optoelectronic properties. We will highlight the key aspects of the PLY derivatives from the design strategies to exploration of the electronic properties. Here, we primarily construct alternating boron (B)- and nitrogen (N)-doped PLY π-aggregates: dimer[12], trimer[12-1], trimer[12-2], tetramer[12]2, pentamer[12]2-1, pentamer[12]2-2, and hexamer[12]3. The geometric and electronic structures show that the short intermolecular distances of the π-aggregates drive the formation of pancake π-π bonding. Significantly, the molecular structures show periodic changes in the π-aggregates, but the first hyperpolarizabilities (ßtot) present unexpected changes, which are found to increase sharply with increasing even layer thickness due to intermolecular charge transfer. The ßtot value of hexamer[12]3 (5.72 × 104 a.u.) is 6.4 times that of tetramer[12]2 (8.95 × 103 a.u.), and is 22.4 times that of dimer[12] (2.55 × 103 a.u.). Thus, constructing π-aggregates can significantly improve the second-order NLO response, which is mainly due to intermolecular charge transfer through pancake π-π bonding of the interlayers.

Hydrogen Migration-Triggered Diradicaloid Singlet-Fission Switch.

We present a theoretical design of the singlet-fission (SF) interconversion between two hydrogen tautomers to attract attention to electronic devices such as switches in the SF field. We develop a tuned π-electron conjugation strategy based on single-hydrogen migration to introduce diradical character and yield low-lying E(T1) levels. Specifically, these objectives could be accomplished by moving one hydrogen from a dihydrogen-substituted pyrazine-fused ring to another unsubstituted pyrazine-fused ring in tetraazatetracenes. The predicted SF efficiency would be expected to exceed 120%. To guide future SF design development, one rule of thumb regarding the S0-state and T1-state emerges from our research: In the S0-state, single-hydrogen migration is crucial for effectively localized electrons, which are the key factor in the formation of diradicals. Conversely, single-hydrogen migration induces a large area of π-electron conjugation in the T1-state, which is completely applied to the electron-hole interaction in the S0 → T1 transition, thereby providing low-lying E(T1) levels. Furthermore, a series of hydrogen tautomers of tetraazaacenes have been proposed as diradicaloid SF switches to verify the reliability of the above rule of thumb. This study will not only help researchers in the photovoltaic field to obtain the desired E(T1) in the future but also broaden the application of hydrogen migration in photovoltaic switch research and supplement the SF database.

A greener catalyst for hydroboration of imines-external electric field modify the reaction mechanism.

Usually, an extra catalyst (for example, the transition metal complexes) need to be used in catalyzing hydroboration, which involved the cost, environment, and so forth. Here, a greener and controllable catalyst-external electric field (EEF) was used to study its effect on hydroboration of N-(4-methylbenzyl)aniline (PhN═CHPhMe) with pinacolboane (HBPin). The results demonstrated that EEF could affect the barrier heights of both two pathways of this reaction. More significantly, flipping the direction of EEF could modify the reaction mechanism to induce a dominant inverse hydroboration at some field strength. That is to say, oriented EEF is a controlling switch for the anti- or Markovnikov hydroboration reaction of imines. This investigation is meaningful for the exploration of greener catalyst for chemistry reaction and guide a new method for the Markovnikov hydroboration addition. © 2019 Wiley Periodicals, Inc.

Strong Pancake 2e/12c Bond in π-Stacking Phenalenyl Derivatives Avoiding Bond Conversion.

The nature of the 2e/12c bond and its conversion to a carbon-carbon single bond in phenalenyl dimers have prompted a great deal of interests recently. In this work, we theoretically investigated a series of π-stacking phenalenyl derivatives with 2e/12c bonding character by density functional theory (DFT) calculations to elucidate origin of this unusual bond conversion. Results show that bond-conversion of the phenalenyl dimer easily occurs at room-temperature both dynamically and thermodynamically. However, bond-conversion of hetero π-stacking adducts, in which the two center carbon atoms were substituted by boron and nitrogen atoms, respectively, is much more difficult, because the 2e/12c bond is stabilized by its charge transfer character. Consequently, the bond-conversion is an endothermic process, albeit with a low conversion barrier. Interestingly, Lewis acid-base interactions would be induced by substitution of the center nitrogen atom to phosphorus atom. The 2e/12c bond is further stabilized by 5.9 kcal mol-1 and its conversion is also thermodynamically unfavorable.

[Correlation analysis of main agronomic traits and contents of diterpene lactones of Andrographis paniculata].

In order to study the correlation between the traits of Andrographis paniculata. The main agronomic traits and the content of four kinds of diterpene lactons were measured by the seedlings and the unmutagenized seeds carried by the spacecraft,and multiple comparisons,correlations and principal component analysis were carried out. The results showed that the agronomic traits of A. paniculata have different degrees of difference after being carried by space. The contents of diterpene lactones were quite different. The variation coefficients of deoxyandrographolide content,fresh weight,leaf dry weight,dehydrated andrographolide content,dry weight,neoandrographolide content and andrographolide content were all over 35%. There was a significant correlation between multiple traits,and the leaf weight ratio was significantly positively correlated with the number of primary tillers,leaf dry weight and dry weight,and was significantly negatively correlated with the content of deoxyandrographolide. Andrographolide content was a significantly negatively correlated with the number of leaves and the number of primary tillers,and positively correlated with the other three lactones. Five principal components were extracted from principal component analysis,and the cumulative contribution rate was 83. 127%,which were yield factor,plant type factor,leaf type factor,component factor and seed weight factor. Among the traits affecting the quality of A. paniculata,the yield factor for reliability of the selection of A. paniculata is higher than other factors. There are abundant variations among the traits of A. paniculata,carried in space which increase the genetic diversity. The principal component analysis method can be used to select the principal component factors according to the breeding requirements,which provides a theoretical basis for the breeding of high-yield and high-quality A. paniculata and the high-yield and stable cultivation of A. paniculata.

Constructing Stable π-Dimers: Two Parallel Pancake π-π Bonds.

Stable phenalenyl (PLY) radical π-dimers still play an important role for new multifunctional materials owing to their intriguing molecular structure and unusual pancake π-π bonding mode. Herein, we design a new biphenalenyl biradicaloid (1) consisting of two PLYs and one benzene ring linkage tethered by single bonds, which presents an open-shell character. Further, three π-dimers (a1, b1, and c1) combined with 1 and conventional biphenalenyl biradicaloid (a, b, and c), which are capable of forming two staggered PLY dimers, exhibiting a short interlayer distance between the monomers. Interestingly, the analysis of the frontier molecular orbital reveals that two bonding orbitals, namely, the two highest occupied molecular orbitals (HOMO and HOMO-1) are doubly occupied. The results reveal that three π-dimers display two parallel pancake bonds. Moreover, they have small diradical and tetraradical characters, large interaction energies, and strong aromaticity, which indicate the stability of these π-dimers. The present work creates a new class of strong pancake bonding and might be utilized in devising an array of materials.

Possible B-C bonding in the hydroboration of benzonitrile by an external electric field.

Generally, the hydroboration of benzonitrile produces B-N containing compounds. However, an unprecedented B-C bond may be formed in the presence of a suitable external electric field (EEF). In reactions of benzonitrile with borane, when the EEF is oriented parallel to the positive direction (N → C) of the N[triple bond, length as m-dash]C bond, the barriers to Markovnikov hydroboration are decreased gradually, meaning the pathway for generating B-C bonds becomes more favorable. Accordingly, hydroboration could be influenced and its selectivity could be controlled by changing the magnitude and direction of an applied EEF.

Stimulating intra- and intermolecular charge transfer and nonlinear optical response for biphenalenyl biradicaloid dimer under an external electric field.

An interesting biphenalenyl biradicaloid (IDPL) dimer consisting of both-middle superimposed phenalenyls and both-end nonsuperimposed phenalenyls has been synthesized, and has attracted intensive research interest due to its intra- and intermolecular interactions and semiconductive characteristics. It is significant that under regulation of the external electric field the directional charge transfer (CT) can produce attractive properties. In the present work, the structure and electronic properties of the IDPL dimer under an external electric field (along the horizontal Fx or the vertical Fz directions) are explored, and the following properties determined: (i) as the horizontal Fx increases, the intramolecular CT becomes larger, which induces the intermolecular CT of the IDPL dimer. (ii) In contrast, as the vertical Fz increases, the large intermolecular CT gives rise to the intramolecular CT of the IDPL dimer. (iii) More importantly, the external electric field effectively regulates and controls the first hyperpolarizability (ßtot) of the IDPL dimer. Compared with the vertical Fz, the horizontal Fx induces a larger first hyperpolarizability (ßtot = 5.48 × 105 a.u.). Furthermore, the application of a uniform external electric field (Fx,y,z) to the IDPL dimer was investigated to define the external electric field direction of the material application. The ßtot values were increased with increasing of the uniform Fx,y,z. Our study provides an effective strategy for developing high-performance NLO materials by tuning the external electric field, and could be of significance for application in switch devices.

[Synthesis and identification of artificial antigen of spinosin].

Immunogenic antigen (spinosin-BSA) and coating antigen (spinosin-OVA) of spinosin were synthesized by sodium periodate oxidation method. UV scanning analysis method showed that these two spinosins were successfully conjugated with carrier protein and the coupling ratio was 17 and 13.7, respectively. Meanwhile, when immunized by spinosin-BSA，the mice can produce anti-spinosin antibodies with the high titer (1:32 000),specificity (IC50 211.6 µg·L⁻¹) and low cross-reaction rate measured by ELISA tests. The artificial antigen of spinosin was successfully synthesized, which can be applied for preparation of monoclonal antibodies and establishment of appropriate immune method.

Tuning the inter-molecular charge transfer, second-order nonlinear optical and absorption spectra properties of a π-dimer under an external electric field.

In this work, we applied an external electric field (F) to a biphenalenyl derivative (BN-PLY2) in the direction of the negative z-axis (F-z) and the positive z-axis (F+z), respectively. The influence of the two directions of F on the molecular structures and electronic properties is investigated, which gives interesting results. Density functional theory (DFT) calculations show that the application of F-z (F-z = 0 to -190 × 10-4) is an advantage toward improving π-dimer stability, which is attributed to an increase in bonding and attractive electrostatic interactions. Interestingly, a large amount of negative charge is induced by applying F-z to the upper layer, resulting in an increase in the electron density in the upper layer, which is the main factor for the formation of a symmetric highest occupied molecular orbital (HOMO) at F-z = -180 × 10-4 au (-9.26 × 109 V m-1). Moreover, when F+z is applied, the HOMO and HOMO-1 undergo orbital interchange in the π-dimer at F+z = 100/110 × 10-4 au. Significantly, the effect of the external electric field effectively regulates the first hyperpolarizabilities (ßtot). When the F+z ranges from 0 to 140 × 10-4 au, the ßtot values slightly decrease to 0 au. Note that, upon increasing F+z, the ßtot values sharply increase to 6.67 × 103 au (F+z = 190 × 10-4 au). Furthermore, the evolutions of the absorption spectra under F might well explain the trend of ßtot values. When the F+z ranges from 0 to 140 × 10-4 au, the broad absorption spikes with a low-energy are significantly blue-shifted, while only absorption spikes with a high-energy are significantly red-shifted (F+z = 140 to 190 × 10-4 au). The present work not only provides a deeper understanding of the relationships between the molecular structure and the electronic properties of a π-dimer system, but can also be developed for designing highly efficient nonlinear optical materials through the influence of an external electric field.

Connecting effect on the first hyperpolarizability of armchair carbon-boron-nitride heteronanotubes: pattern versus proportion.

Carbon-boron-nitride heteronanotubes (BNCNT) have attracted a lot of attention because of their adjustable properties and potential applications in many fields. In this work, a series of CA, PA and HA armchair BNCNT models were designed to explore their nonlinear optical (NLO) properties and provide physical insight into the structure-property relationships; CA, PA and HA represent the models that are obtained by doping the carbon segment into pristine boron nitride nanotube (BNNT) fragments circularly around the tube axis, parallel to the tube axis and helically to the tube axis, respectively. Results show that the first hyperpolarizability (ß0) of an armchair BNCNT model is dramatically dependent on the connecting patterns of carbon with the boron nitride fragment. Significantly, the ß0 value of PA-6 is 2.00 × 10(4) au, which is almost two orders of magnitude larger than those (6.07 × 10(2) and 1.55 × 10(2) au) of HA-6 and CA-6. In addition, the ß0 values of PA and CA models increase with the increase in carbon proportion, whereas those of HA models show a different tendency. Further investigations on transition properties show that the curved charge transfer from N-connecting carbon atoms to B-connecting carbon atoms of PA models is essentially the origin of the big difference among these models. This new knowledge about armchair BNCNTs may provide important information for the design and preparation of advanced NLO nano-materials.

Two-electron/24-center (2e/24c) bonding in novel diradical π-dimers.

A series of diradical π-dimers 2 with interesting pancake-shaped 2e/24c π-π bonding character were designed and investigated based on the famous phenalenyl (PLY) π-dimer with 2e/12c π-π bonding character. The position of stronger interaction between two layers of radicals was found by the Wiberg bond index (WBI) maximum component. Further, the different contributions of the interaction energy were analyzed quantitatively by energy decomposition analysis (EDA). Among these new diradical π-dimers, 2180 has the smallest layer distance and the largest interaction between two layers of radicals. The unusual PLY analogues can provide new insights into the unique features of two-electron/multicenter (2e/mc) π-π bonding.

The polar 2e/12c bond in phenalenyl-azaphenalenyl hetero-dimers: Stronger stacking interaction and fascinating interlayer charge transfer.

An increasing number of chemists have focused on the two-electron/multicenter bond (2e/mc) that was first introduced to interpret the bonding mechanism of radical dimers. Herein, we report the polar two-electron/twelve center (2e/12c) bonding character in a series of phenalenyl-azaphenalenyl radical hetero-dimers. Interestingly, the bonding energy of weaker polar hetero-dimer (P-TAP) is dominated by the overlap of the two different singly occupied molecular orbital of radicals, while that of stronger polar hetero-dimer (P-HAP) is dominated by the electrostatic attraction. Results show that the difference between the electronegativity of the monomers plays a prominent role in the essential attribution of the polar 2e/12c bond. Correspondingly, a stronger stacking interaction in the hetero-dimer could be effectively achieved by increasing the difference of nitrogen atoms number between the monomers. It is worthy of note that an interesting interlayer charge transfer character is induced in the polar hetero-dimers, which is dependent on the difference between the electronegativity of the monomers. It is our expectation that the new knowledge about the bonding nature of radical hetero-dimers might provide important information for designing radical based functional materials with various applications.

How does hybrid bridging core modification enhance the nonlinear optical properties in donor-π-acceptor configuration? A case study of dinitrophenol derivatives.

This study spotlights the fundamental insights about the structure and static first hyperpolarizability (ß) of a series of 2,4-dinitrophenol derivatives (1-5), which are designed by novel bridging core modifications. The central bridging core modifications show noteworthy effects to modulate the optical and nonlinear optical properties in these derivatives. The derivative systems show significantly large amplitudes of first hyperpolarizability as compared to parent system 1, which are 4, 46, 66, and 90% larger for systems 2, 3, 4, and 5, respectively, at Moller-Plesset (MP2)/6-31G* level of theory. The static first hyperpolarizability and frequency dependent coupled-perturbed Kohn-Sham first hyperpolarizability are calculated by means of MP2 and density functional theory methods and compared with respective experimental values wherever possible. Using two-level model with full-set of parameters dependence of transition energy (ΔΕ), transition dipole moment (µ(0)) as well as change in dipole moment from ground to excited state (Δµ), the origin of increase in ß amplitudes is traced from the change in dipole moment from ground to excited state. The causes of change in dipole moments are further discovered through sum of Mulliken atomic charges and intermolecular charge transfer spotted in frontier molecular orbitals analysis. Additionally, analysis of conformational isomers and UV-Visible spectra has been also performed for all designed derivatives. Thus, our present investigation provides novel and explanatory insights on the chemical nature and origin of intrinsic nonlinear optical (NLO) properties of 2,4-dinitrophenol derivatives.

Modulating the charge transfer of D-S-A molecules: structures and NLO properties.

Very recently, the investigation of an Li atom doped effect on the "through-space" electronic interaction (S) of a donor-S-acceptor (D-S-A, 1) shows that the Li-doping effect can modulate the first hyperpolarizability of 1 ( Dyes Pigm. 2014 , 106 , 7 - 13 ). Can we further enhance the first hyperpolarizability (ßtot) of 1 by modulating the charge transfer of D-S-A molecules? The present work indicates that the ßtot value can be successfully modulated by replacing the sp(2)-hybridized CH═CH moiety connected with substituted para-cyclophane (PCP). On the other hand, the NO2 contributes more than NH2 to the ßtot value. The results of time-dependent density functional theory (TD-DFT) provide a good explanation for the variation in the ßtot value. Interestingly, the ßtot value of 3 (4.09 × 10(3) au) is larger than 1.52 × 10(3) au of 4, while the difference between the dipole moments (Δµ) of the ground state and the crucial excited state of 3 (2.93 D) is smaller than that of 4 (7.79 D). Further, the charge-transfer excitation length (D(CT)) of 3 (1.41 Å) is smaller than that of 4 (2.89 Å). Therefore, D(CT) is the major factor in determining the Δµ value.

Influence of spiral framework on nonlinear optical materials.

A series of spiral donor-π-acceptor frameworks (i.e. 2-2, 3-3, 4-4, and 5-5) based on 4-nitrophenyldiphenylamine with π-conjugated linear acenes (naphthalenes, anthracenes, tetracenes, and pentacenes) serving as the electron donor and nitro (NO2 ) groups serving as the electron acceptor were designed to investigate the relationships between the nonlinear optical (NLO) responses and the spirality in the frameworks. A parameter denoted as D was defined to describe the extent of the spiral framework. The D value reached its maximum if the number of NO2 groups was equal to the number of fused benzene rings contained in the linear acene. A longer 4-nitrophenyldiphenylamine chain led to a larger D value and, further, to a larger first hyperpolarizability. Different from traditional NLO materials with charge transfer occurring in the one-dimensional direction, charge transfer in 2-2, 3-3, 4-4, and 5-5 occur in three-dimensional directions due to the attractive spiral frameworks, and this is of great importance in the design of NLO materials. The origin of such an enhancement in the NLO properties of these spiral frameworks was explained with the aid of molecular orbital analysis.

A designed bithiopheneimide-based conjugated polymer for organic photovoltaic with ultrafast charge transfer at donor/PC(71)BM interface: theoretical study and characterization.

In the current work, a series of bithiopheneimide (BTI)-based D-A copolymers were investigated based on the reported PDTSBTI (1) to screen excellent molecules toward organic photovoltaic (OPV) donor materials. It is found that the PCE based on the proposed derivative 4, where the silicon atom is replaced with vinyl and cyano groups on the DTS unit, shows a 70 percent improvement by Scharber diagrams compared with its prototype 1. Then, the charge transfer dynamics of 1/PC71BM and 4/PC71BM were investigated, including the intermolecular charge transfer (inter-CT) and recombination (inter-CR) rates. The theoretical data demonstrate that the ratio kinter-CT/kinter-CR of 4/PC71BM heterojunction is about 1 × 10(5) times higher than that of 1/PC71BM. These results clearly reveal that the designed donor molecule 4 will be a promising candidate for high-performance OPV device. We expect that this work from electron processing at the D/A interface may provide a theoretical guideline for further optimization and design of organic copolymer donor materials.