Insight into Hydrogenation Selectivity of the Electrocatalytic Nitrate-to-Ammonia Reduction Reaction via Enhancing the Proton Transport.

The electrocatalytic nitrate-to-ammonia reduction reaction route (NARR) is one of the emerging routes toward green ammonia synthesis, and its conversion efficiency is controlled mainly by the hydrogenation selectivity. This study proposed a likely NARR route feasible and effective even in a neutral condition. Its high catalytic selectivity and efficiency were achieved by a switch of the sulfate solution to the phosphate buffer solution (PBS), while conditions of NO3 - concentration, pH, and applied potential were maintained unchanged. Specifically, the faradaic efficiencies toward NH3 (FE NH 3 ) in Na2 SO4 were as low as 9.8, 19.8, and 11.4 % versus remarkably jumping to 82.8, 90.5, and 89.5 % in PBS under -0.75, -1.0, and -1.25 V, respectively. The corresponding faradaic efficiencies toward NO2 - (FE NO 2 - ), 77.0, 69.2, and 73.7 % in Na2 SO4 , significantly dropped to10.8, 7.4, and 4.4 % in PBS, evidencing an unexpected selectivity reversal of the nitrate reduction from NO2 - to NH3 . This insight was further revealed by the visualization of the pH gradient near the electrode surface during NARR and confirmed by density functional theory calculations; PBS notably facilitated the proton transport and active mitigation over the proton transfer barrier. The use of PBS resulted in a maximal partial current density toward NH3 (J NH 3 ) and NH3 formation rate (r NH 3 ) up to 133.5 mA cm-2 and 1.74×10-7  mol s-1 cm-2 in 1.0 m KNO3 at -1.25 V.

[Research and development strategies of new Chinese medicines based on new regulations].

In recent years, only a small number of new Chinese medicines have been approved for marketing, which has embodied the bottleneck in the development of the Chinese medicine industry. To tackle this problem, the National Medical Products Administration has issued a series of regulations and technical requirements. In the context of new regulations, this study deeply explored the research and development strategies of new Chinese medicines under the guidance of the new classification of drug registration, and discussed the key technical issues in the research and development.

A review on traditional uses, phytochemistry, pharmacology, toxicology and the analytical methods of the genus Nardostachys.

ETHNOPHARMACOLOGICAL RELEVANCE: The plants of the genus Nardostachys (Caprifoliaceae) have been used for a long history in different cultural systems of medicine, including Chinese, Ayurvedic, Korean folk medicine and Islamic, for treatments of disorders in nervous, digestive, cardiovascular and integumentary systems. AIM OF THE REVIEW: This review aims to provide comprehensive information on Nardostachys plants including botany update, traditional uses, data mining of uses in traditional Chinese medicine (TCM) and current Chinese medicinal patents, chemical constituents, pharmacological effects, toxicity and analytical method studies. MATERIALS AND METHODS: Studies of the genus Nardostachys were collected via Google Scholar and Baidu Scholar, ScienceDirect, SciFinder, Wiley Online Library, ACS Publications, NLM/NCBI, Web of Science, CNKI, WANFANG DATA, EMBASE, Huabeing database and Traditional Chinese Medicine Resource Network and libraries. Some local books, PhD or MS's dissertations were also included. The literatures cited in this review covered the period from 1962 to March 2021. The Plant List and Kew Herbarium Catalogue databases were used to authenticate the scientific name. RESULTS: Botany description of Nardostachys genus is updated. Analysis of the literatures indicates that Nardostachys species are valuable herbs with therapeutic potentials for various disorders. Data mining on ancient TCM prescriptions and current Chinese medicinal patents containing Nardostachys revealed its common compatibility with other herbs in China. Phytochemical studies identified terpenoids and phenolic compounds as the main constituents in the genus Nardostachys and sesquiterpenoids as the major bioactive components. Experimental studies demonstrated that crude extracts, major fractions and the main constituents from Nardostachys species mainly exhibited pharmacological activities on nervous, digestive, cardiovascular and skin systems. Further, in vivo and in vitro toxicological studies demonstrated that Nardostachys plants showed either no or low toxicities, except at high doses. Finally, methods of qualitative and quantitative analyses on chemical constituents of genus Nardostachys were summarized, including TLC/HPTLC, GC and HPLC/UPLC methods, combined with common detectors including PDA, DAD and MS. CONCLUSIONS: This review summarizes the progress on phytochemistry, pharmacology, toxicology and analytical methods of the genus Nardostachys. Studies demonstrate traditional uses of the genus Nardostachys, and reveal novel bioactive effects for clinical uses. These achievements expand our knowledge on the genus Nardostachys and its clinical value.

Graphene-Like Hydrogen-Bonded Melamine-Cyanuric Acid Supramolecular Nanosheets as Pseudo-Porous Catalyst Support.

Behaving as structural protectors and electronic modulators, catalyst supports such as graphene derivatives are generally constructed by covalent bonds. Here, hydrogen-bonded ultrathin nanosheets are reported as a new type of catalyst support. Melamine (M) and cyanuric acid (CA) molecules self-assemble to form the graphite-like hydrogen-bonded co-crystal M-CA, which can be easily exfoliated by ultrasonic treatment to yield ultrathin nanosheets with thickness of ≈1.6 nm and high stability at pH = 0. The dynamic nanosheets form adaptive defects/pores in the synthetic process of CoP nanoparticles, giving embedded composite with high hydrogen evolution activity (overpotential of 66 mV at 10 mA cm-2 ) and stability. Computational calculations, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy unveil the electron modulation effects of the nanosheets. This pseudo-porous catalyst support also can be applied to other metal phosphides.

Ultrathin 2D Copper(I) 1,2,4-Triazolate Coordination Polymer Nanosheets for Efficient and Selective Gene Silencing and Photodynamic Therapy.

Gene silencing holds promise for cancer therapeutics because of its potential to inhibit genes involved in tumor development. However, gene silencing is still restricted by its limited efficacy and safety. Nanoscale coordination polymers (CPs) emerge as promising nanocarriers for gene delivery, but their responsiveness and potential therapeutic properties have rarely been explored simultaneously. Here, multifunctional ultrathin 2D nanosheets of Cu(I) 1,2,4-triazolate CP with a thickness of 4.5 ± 0.8 nm are synthesized using a bottom-up method. These CP nanosheets can act as both an effective DNAzyme nanocarrier for gene therapy and an intrinsic photosensitizer for hypoxia-tolerant type I photodynamic therapy (PDT), which is ascribed to the Fenton-like reaction. Because of the glutathione (GSH)-responsiveness of the CP nanosheets, DNAzyme-loaded CP nanosheets exhibit excellent cancer-cell-targeting gene silencing of the early growth response factor-1 (EGR-1), with messenger RNA inhibited by 84% in MCF-7 (human breast cancer cells) and only 6% in MCF-10A (normal human mammary epithelial cells). After tail intravenous injection into MCF-7-tumor-bearing mice, the CP nanosheets loaded with chlorin-e6-modified DNAzyme under photoirradiation show a high antitumor efficacy (88.0% tumor regression), demonstrating a promising therapeutic platform with efficient and selective gene silencing and PDT of cancer.

Qingwenzhike Prescription Alleviates Acute Lung Injury Induced by LPS via Inhibiting TLR4/NF-kB Pathway and NLRP3 Inflammasome Activation.

Background: Acute lung injury (ALI) is characterized by dysfunction of the alveolar epithelial membrane caused by acute inflammation and tissue injury. Qingwenzhike (QWZK) prescription has been demonstrated to be effective against respiratory viral infections in clinical practices, including coronavirus disease 2019 (COVID-19) infection. So far, the chemical compositions, protective effects on ALI, and possible anti-inflammatory mechanisms remain unknown. Methods: In this study, the compositions of QWZK were determined via the linear ion trap/electrostatic field orbital trap tandem high-resolution mass spectrometry (UHPLC-LTQ-Orbitrap MS). To test the protective effects of QWZK on ALI, an ALI model induced by lipopolysaccharide (LPS) in rats was used. The effects of QWZK on the LPS-induced ALI were evaluated by pathological changes and the number and classification of white blood cell (WBC) in bronchoalveolar lavage fluid (BALF). To investigate the possible underlying mechanisms, the contents of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein (MCP-1), interleukin-1ß (IL-1ß), interleukin-18 (IL-18), and immunoregulatory-related factors interferon-γ (IFN-γ) were detected by ELISA. Furthermore, the expression of Toll-like receptor 4 (TLR4), p-IKKα/ß, IKKα, IKKß, p-IκBα, IκBα, p-NF-κB, nuclear factor-κB (NF-κB), NOD-like receptor family pyrin domain containing 3 (NLRP3), cleaved caspase-1, pro-caspase-1, apoptosis-associated speck-like protein containing CARD (ASC), and ß-actin were tested by Western blot. Results: A total of 99 compounds were identified in QWZK, including 33 flavonoids, 23 phenolic acids, 3 alkaloids, 3 coumarins, 20 triterpenoids, 5 anthraquinones, and 12 others. ALI rats induced by LPS exhibited significant increase in neutrophile, significant decrease in lymphocyte, and evidently thicker alveolar wall than control animals. QWZK reversed the changes in WBC count and alveolar wall to normal level on the model of ALI induced by LPS. ELISA results revealed that QWZK significantly reduced the overexpression of proinflammatory factors IL-6, TNF-α, MCP-1, IL-1ß, IL-18, and IFN-γ induced by LPS. Western blot results demonstrated that QWZK significantly downregulated the overexpression of TLR4, p-IKKα/ß, p-IκBα, p-NF-κB, NLRP3, cleaved caspase-1, and ASC induced by LPS, which suggested that QWZK inhibited TLR4/NF-κB signaling pathway and NLRP3 inflammasomes. Conclusions: The chemical compositions of QWZK were first identified. It was demonstrated that QWZK showed protective effects on ALI induced by LPS. The possible underlying mechanisms of QWZK on ALI induced by LPS was via inhibiting TLR4/NF-kB signaling pathway and NLRP3 inflammasome activation. This work suggested that QWZK is a potential therapeutic candidate for the treatments of ALI and pulmonary inflammation.

Antidepressant activities and regulative effects on serotonin transporter of Nardostachys jatamansi DC.

ETHNOPHARMACOLOGICAL RELEVANCE: Nardostachys jatamansi (D.Don) DC. (family Caprifoliaceae, NJ) is well-documented and commonly used in the systems of traditional medicine in China, Tibet, Nepal, Bhutan, India and Japan for curing digestive and neuropsychiatric disorders with a long history of medication. However, the possible action mechanisms of antidepressant effects of NJ remain unraveled. AIM OF THE STUDY: The aim of this study was to systematically investigate chemical substances of NJ and their effects on serotonin transporter (SERT) in antidepressant activity. MATERIALS AND METHODS: Antidepressant effects of total methanol extract of NJ were evaluated by tail suspension test (TST) and open field test (OFT). Then the total extract was analyzed by ultra-high-performance liquid chromatography (UHPLC) method, and its effect on SERT activity was evaluated by high content assay (HCA) to determine half maximal effective concentration (EC50). This total extract was subfractioned into twenty subfractions by preparative high-performance liquid chromatography (p-HPLC) method, and 'subfraction-SERT activity' relationship curve was fitted with medians of the retention time of those subfractions and their SERT activity values. Then, the fraction NJFr.01 enriched with SERT enhancers was optimized, prepared and analyzed by UHPLC method. Antidepressant effects of the fraction NJFr.01 were evaluated by TST and OFT. Further, major constituents of the total extract and fraction NJFr.01 were isolated by p-HPLC and identified by extensive nuclear magnetic resonance (NMR) analyses and comparisons with those reported data, and their SERT activities were also evaluated. Finally, antagonistic effects of chlorogenic acid and desoxo-narchinol A against fluoxetine on SERT were evaluated. RESULTS: Results of TST and OFT demonstrated antidepressant effects of toatal extract of NJ. The EC50 of total extract on SERT enhancement was 31.63 µg/mL. The fitted 'subfraction-SERT activity' relationship curve revealed that fraction NJFr.01 was enriched with SERT enhancing constituents. Both total extract and fraction NJFr.01 significantly enhanced SERT activity, while the rest fraction NJFr.02 didn't show any SERT activity. Then, antidepressant effects of fraction NJFr.01 were demonstrated by TST and OFT. Further, phytochemistry investigation and UHPLC analyses confirmed the identification of fourteen constituents in the total extract of NJ, including 7-oxonardinoperoxide (1), desoxo-narchinol A (2), kanshone B (3), narchinol B (4), nardosinonediol (5), kanshone A (6), 1-hydroxylaristolone (7), debilon (8), nardosinone (9), kanshone H (10), 1,8,9,10-tetradehydroaristolan-2-one (11), (-)-aristolone (12), 1(10)-aristolene-2-one (13) and jatamol A (14), and seven constituents in the fraction NJFr.01, including chlorogenic acid (15), 8α-dihydrogeniposide (16), 7-deoxy-8-epi-loganic acid (17), adoxosidic acid (18), 8-epi-loganic acid (19), 8α-6,7-dihydroapodantheroside acetate (20) and 6″-acetylpatrinalloside (21). Their structures were established by NMR analyses and comparisons with those reported data. HCA results of these constituents demonstrated the major components of fraction NJFr.01 enhanced SERT activity. Antagonistic results showed that chlorogenic acid and desoxo-narchinol A reversed inhibition effect of fluoxetine on SERT activity. CONCLUSION: This study first systematically expatiated the roles of SERT activity in antidepressant effects of NJ, including total methanol extract and the water-soluble fraction NJFr.01 enriched with SERT enhancing constituents. This is the first report of natural SERT enhancing extract and fractions with antidepressant potential in NJ.

A Hydrogen-Bonded yet Hydrophobic Porous Molecular Crystal for Molecular-Sieving-like Separation of Butane and Isobutane.

Porous molecular crystals sustained by hydrogen bonds and/or weaker connections are an intriguing type of adsorbents, but they rarely demonstrate efficient adsorptive separation because of poor structural robustness and tailorability. Herein, we report a porous molecular crystal based on hydrogen-bonded cyclic dinuclear AgI complex, which exhibits exceptional hydrophobicity with a water contact angle of 134°, and high chemical stability in water at pH 2-13. The seemingly rigid adsorbent shows a pore-opening or nonporous-to-porous type butane adsorption isotherm and complete exclusion of isobutane, indicating potential molecular sieving. Quantitative column breakthrough experiments show slight co-adsorption of isobutane with an experimental butane/isobutane selectivity of 23, and isobutane can be purified more efficiently than for butane. In situ powder/single-crystal X-ray diffraction and computational simulations reveal that a trivial guest-induced structural transformation plays a critical role.

Protective Effects and Possible Mechanisms of Actions of Bushen Cuyun Recipe on Diminished Ovarian Reserve Induced by Cyclophosphamide in Rats.

BACKGROUNDS: Diminished ovarian reserve (DOR) contributes significantly to female infertility. Bushen Cuyun Recipe (BCR, Tradename Yueliang Yin), a product marketed in China, has shown effects in the treatment of female infertility in clinical practices of traditional Chinese medicine (TCM). In this study, we aimed to investigate the chemical compositions of BCR and its efficacy based on scientific evidence and pharmacological mechanisms in DOR treatments. METHODS: The chemical compositions of BCR were determined by the UHPLC-LTQ-Orbitrap MS method. DOR was induced in a rat model by intraperitoneal injection of cyclophosphamide (CTX) 90 mg/kg once. After the CTX treatment for 14 days, rats were intragastrically administrated deionized water, dehydroepiandrosterone (DHEA), or BCR in low, middle, and high doses for 30 days. Ovarian index, ovarian morphology, follicle number, and anti-Müllerian hormone (AMH) in serum were determined to assess the effects of BCR. To investigate possible action mechanisms, network pharmacological analysis was used to predict possible pathways in the effects of BCR on female infertility. In experimental studies, the contents of hormones in the hypothalamic-pituitary-ovarian axis (HPOA, including estradiol (E2), follicle-stimulating hormone (FSH), and gonadotropin-releasing hormone (GnRH)) and pyroptosis-related proteins, including gasdermin D (GSDMD), caspase-1, and interleukin-18 (IL-18), in ovarian were detected by ELISA, immunofluorescence and Western blot. RESULTS: Chemical studies revealed a total 84 components in BCR, which included 43 flavonoids, 13 triterpenoids, 11 phenolic acids, 8 alkaloids, 1 coumarin, 1 anthraquinone, and 7 other components. After treatments with BCR, the ovarian morphology, ovarian index, estrous cycle, growing follicles and corpus luteum from last ovulation, and serum AMH in DOR rats were significantly improved. Network pharmacological analysis suggested that the NOD-like receptor signaling pathway ranked No. 1 among the mechanisms by which BCR affects female infertility. Experimental results demonstrated that the content of serum FSH in DOR rats was significantly decreased and the contents of serum GnRH and E2 were significantly elevated after BCR treatment and that the elevated level of GSDMD, caspase-1, and IL-18 was significantly reversed in BCR-treated rats. CONCLUSIONS: The chemical compositions of BCR were first identified in the present study. BCR was demonstrated to show protective effects on DOR. The possible mechanisms of BCR on DOR might be mediated by regulating gonadal hormones of the HPOA and protecting granulosa cells in ovary against pyroptosis.

Bioactivities of serotonin transporter mediate antidepressant effects of Acorus tatarinowii Schott.

ETHNOPHARMACOLOGICAL RELEVANCE: Acrorus tatarinowii Schott has been widely used in the treatments of neuropsychiatric and digestive disorders in clinical practices of traditional Chinese medicine for thousands of years. Both clinical and preclinical studies demonstrated antidepressant effects of A. tatarinowii. However, the possible action mechanisms of antidepressant effects of A. tatarinowii remain unraveled. AIM OF THE STUDY: The present study aimed to investigate the roles of serotonin transporter (SERT) in antidepressant effects of A. tatarinowii. MATERIALS AND METHODS: Antidepressant effects of water extract of A. tatarinowii were evaluated by forced swimming test (FST), tail suspension test (TST) and locomotor activity test. The water extract was analyzed by ultra high performance liquid chromatography (UPLC) method. Two major fractions of A. tatarinowii, petroleum ether extract and water extract after petroleum ether processed, were prepared and analyzed by UPLC method. Further, volatile oil extracted by ether extraction, solid phase micro-extraction (SPME) and hydro-distillation were compared and analyzed by gas chromatography-mass spectrometer (GC-MS) method. Finally, major constituents of water extract of A. tatarinowii were isolated by preparative high performance liquid chromatography (HPLC) and identified by extensive spectroscopic analyses. Effects of all of the above mentioned samples on SERT activity were tested by a high content assay (HCA). RESULTS: Results of FST, TST and locomotor activity confirmed that water extract of A. tatarinowii significantly decreased mice immobility time but did not change mice locomotor activity. UPLC analysis results revealed that the water extract contained trace amount of ß-asarone (0.0004206%) and α-asarone (0.0001918%). HCA results demonstrated that the water extract significantly enhanced SERT activity at 100 µg/mL. Further, GC-MS and UPLC analyses revealed that petroleum ether extract contained high content of ß-asarone (45.63%) and α-asarone (12.50%). GC-MS analysis results demonstrated that the volatile oil extracted by ether extraction, SPME and hydro-distillation contained similar major components. HCA results verified that the petroleum ether extract significantly enhanced SERT activity at 1.56 µg/mL. Moreover, UPLC analysis of water extract after petroleum ether processed did not show any characteristic peaks. HCA results demonstrated that this extract significantly inhibited SERT activity at 50-100 µg/mL. Finally, phytochemistry investigation on the water extract of A. tatarinowii afforded seven constituents including veratric acid (9), anisic acid (7), 3,4,5-trimethoxybenzoic acid (3), trans-isoferulic acid (2), 2,4,5-trimethoxybenzoic acid (11), 4-hydroxybenzoic acid (6) and syringic acid (13). Their structures were established on the basis of nuclear magnetic resonance (NMR) and mass spectrometer (MS) data and comparative UPLC analyses. HCA results demonstrated the major components of the water extract of A. tatarinowii demonstrated SERT enhancement/inhibition activities. CONCLUSIONS: This study first systematically demonstrated the roles of SERT activity in antidepressant effects of A. tatarinowii, including water extract, major fractions and main constituents. These results revealed that A. tatarinowii could regulate SERT activities in bidirectional ways.

Benzimidazolone-based selective σ2 receptor ligands: Synthesis and pharmacological evaluation.

Sigma receptors (σRs) are considered to be a significant and valid target for developing new medications to address several diseases. Their potential involvement in numerous central nervous system disorders, neuropathic pain, addiction, and cancer has been extensively reported. In particular, the σ2R has been identified as potential target for the development of pharmaceutical agents intended to treat the negative effects associated with drugs of abuse. As a continuation of our previous efforts to develop new selective σ2R ligands, a series of benzimidazolone derivatives were designed, synthesized, and characterized. The newly synthesized ligands were evaluated through in vitro radioligand binding assays to determine their affinity and selectivity towards both σ1 and σ2 receptors. Several derivatives displayed high affinity for the σ2R (Ki = 0.66-68.5 nM) and varied from preferring to selective, compared to σ1R (σ1/σ2 = 5.8-1139). Among them, compound 1-{4-[4-(4-fluorophenyl)piperazin-1-yl]butyl}-3-propyl-1,3-dihydrobenzimidazol-2-one dihydrochloride (14) displayed the ability to produce a dose-dependent reduction in the convulsive effects of cocaine in a rodent model after injecting 10 mg/kg (i.p.). These preliminary results support the use of selective σ2R ligands in the development of useful pharmacological tools or potential pharmacotherapies for cocaine toxicity.

Non-3d Metal Modulation of a Cobalt Imidazolate Framework for Excellent Electrocatalytic Oxygen Evolution in Neutral Media.

Cobalt imidazolate frameworks are classical electrocatalysts for the oxygen evolution reaction (OER) but suffer from the relatively low activity. Here, a non-3d metal modulation strategy is presented for enhancing the OER activity of cobalt imidazolate frameworks. Two isomorphous frameworks [Co4 (MO4 )(eim)6 ] (M=Mo or W, Heim=2-ethylimidazole) having Co(eim)3 (MO4 ) units and high water stabilities were designed and synthesized. In different neutral media, the Mo-modulated framework coated on a glassy carbon electrode shows the best OER performances (1 mA cm-2 at an overpotential of 210 mV in CO2 -saturated 0.5 m KHCO3 electrolyte and 2/10/22 mA cm-2 at overpotential of 388/490/570 mV in phosphate buffer solution) among non-precious metal catalysts and even outperforms RuO2 . Spectroscopic measurements and computational simulations revealed that the non-3d metals modulate the electronic structure of Co for optimum reactant/product adsorption and tailor the energy of rate-determining step to a more moderate value.

Six kanshone C-derived sesquiterpenoid hybrids nardochalaristolones A-D, nardoflavaristolone A and dinardokanshone F from Nardostachys jatamansi DC.

Four sesquiterpenoid-chalcone hybrids (nardochalaristolones A-D, 1-4), a pair of epimeric sesquiterpenoid-flavonone hybrids ((2'S)- and (2'R)-nardoflavaristolone A, 5 and 6), and a sesquiterpenoid dimer (dinardokanshone F, 7), all sharing a kanshone C-derived sesquiterpenoid unit, were isolated from the underground parts of Nardostachys jatamansi (D.Don) DC. Their structures were elucidated by analysis of the extensive spectroscopic data, and the absolute configurations were established by analysis of 2D NMR spectroscopic data including NOESY data, combined with comparisons of experimental and calculated electronic circular dichroism spectra. Further, the plausible biosynthetic pathways for these compounds were proposed. And the results of SERT activity assay revealed that nardochalaristolones C-D (3 and 4) and nardoflavaristolone A (5 and 6) significantly enhanced SERT activity, while other compounds didn't show any SERT regulatory activities.

Dinardokanshones C-E, isonardoeudesmols A-D and nardoeudesmol D from Nardostachys jatamansi DC.

Dinardokanshones C-E, three sesquiterpenoid dimers comprising an unusual nornardosinane-type sesquiterpenoid core and an aristolane-type sesquiterpenoid unit conjugated by an extra pyran or furan ring, together with monomeric sesquiterpenoids isonardoeudesmols A-D and nardoeudesmol D, were isolated from the underground parts of Nardostachys jatamansi DC. Structures of the eight compounds were elucidated by analysis of the extensive spectroscopic data, and their absolute configurations were established by analysis of NOESY and X-ray diffraction data, combined with computational electronic circular dichroism (ECD) calculations. The results of SERT activity assay revealed that isonardoeudesmol D and nardoeudesmol D significantly inhibited SERT activity, while dinardokanshones D-E and isonardoeudesmols B-C significantly enhanced SERT activity, among which dinardokanshone D exhibited the strongest effect.

Electrochemical Exfoliation of Pillared-Layer Metal-Organic Framework to Boost the Oxygen Evolution Reaction.

Two-dimensional (2D) materials and ultrathin nanosheets are advantageous for elevating the catalysis performance and elucidating the catalysis mechanism of heterogeneous catalysts, but they are mostly restricted to inorganic or organic materials based on covalent bonds. We report an electrochemical/chemical exfoliation strategy for synthesizing metal-organic 2D materials based on coordination bonds. A catechol functionalized ligand is used as the redox active pillar to construct a pillared-layer framework. When the 3D pillared-layer MOF serves as an electrocatalyst for water oxidation (pH 13), the pillar ligands can be oxidized in situ and removed. The remaining ultrathin (2 nm) nanosheets of the metal-organic layers are an efficient catalyst with overpotentials as low as 211 mV at 10 mA cm-2 and a turnover frequency as high as 30 s-1 at an overpotential of 300 mV.

A Simple and Rapid UPLC-PDA Method for Quality Control of Nardostachys jatamansi.

Nardostachys jatamansi is a well-documented herbal agent used to treat digestive and neuropsychiatric disorders in oriental medicinal systems. However, few simple, rapid, and comprehensive methods were reported for quality assessment and control of N. jatamansi. Herein, a UPLC with photodiode array detection method was developed for both fingerprint investigation of N. jatamansi and simultaneous quantitative analysis of the six serotonin transporter modulatory constituents in N. jatamansi. For chromatographic fingerprinting, 24 common peaks were selected as characteristic peaks to assess the consistency of N. jatamansi samples from different retail sources. Six of the common peaks (5, 7, 12: , and 16:  - 18: ) were identified as desoxo-narchinol A, buddleoside, isonardosinone, nardosinone, kanshone H, and (-)-aristolone, respectively, by phytochemical investigation. Five of the six compounds significantly either enhanced or inhibited serotonin transporter activity, while (-)-aristolone (18: ) didn't show any serotonin transporter activity. In quantitative analysis, the six compounds showed good linearity (r > 0.999) within test ranges. The precision, expressed as relative standard deviation, was in the range of 0.25 - 2.77%, and the recovery of the method was in the range of 92 - 105%. The UPLC-photodiode array detection-based fingerprint analysis and quantitative methods reported here could be used for routine quality control of N. jatamansi.

[Fast-onset antidepressant potentials of essential oil of herbs].

The existing antidepressants demonstrated delayed onset of clinical effects, so fast-onset antidepressants are required. Essential oil of herbs showed potentials fast-onset antidepressant potential. First, its aromatic odor can directly activate olfactory nerves; its high lipophilicity causes a high blood-brain barrier penetration rate; and its high volatility is suitable for nasal-brain targeting and inhalation delivery. Therefore, essential oils can rapidly regulate brain functions by multiple ways, suggesting a fast-onset antidepressant potential. Second, the advance of studies on chemistry and pharmacology of antidepressant essential oils demonstrated chemical substances, antidepressant effects and possible action mechanisms of antidepressant essential oils. Third, the effect of essential oils' antidepressant components on fast-onset antidepressant targets was investigated. It was found that chemical constituents of essential oils antagonized NMDA receptor activities, suggesting that essential oils have fast-onset antidepressant effect. Finally, characteristics of essential oils, fast-onset antidepressant targets and drug delivery methods are integrated to give full play to essential oils' fast-onset antidepressant advantage and provide a new direction for new drug discovery.

Novel serotonin transporter regulators: Natural aristolane- and nardosinane- types of sesquiterpenoids from Nardostachys chinensis Batal.

Serotonin transporter (SERT) is a classic target of drug discovery for neuropsychiatric and digestive disorders, and against those disorders, plants of Nardostachys genus have been valued for centuries in the systems of Traditional Chinese Medicine, Ayurvedic and Unani. Herein, chemical investigation on the roots and rhizomes of Nardostachys chinensis Batal. led to the isolation of forty sesquiterpenoids including six new aristolane-type sesquiterpenoids and six new nardosinane-type sesquiterprenoids. Their structures were elucidated by extensive spectroscopic methods, combined with analyses of circular dichroism and single-crystal X-ray diffraction data. To explore natural product scaffolds with SERT regulating activity, a high-content assay for measurement of SERT function in vitro was conducted to evaluate the SERT regulating properties of these isolates. In conclusion, eleven compounds could be potential natural product scaffolds for developing drug candidates targeting SERT. Among which, kanshone C of aristolane-type sesquiterpenoid inhibited SERT most strongly, while desoxo-nachinol A of nardosinane-type sesquiterpenoid instead enhanced SERT potently.

Hyperfine adjustment of flexible pore-surface pockets enables smart recognition of gas size and quadrupole moment.

The pore size and framework flexibility of hosts are of vital importance for molecular recognition and related applications, but accurate control of these parameters is very challenging. We use the slight difference of metal ion size to achieve continuous hundredth-nanometer pore-size adjustments and drastic flexibility modulations in an ultramicroporous metal-organic framework, giving controllable N2 adsorption isotherm steps, unprecedented/reversed loading-dependence of H2 adsorption enthalpy, quadrupole-moment sieving of C2H2/CO2, and an exceptionally high working capacity for C2H2 storage under practical conditions (98 times that of an empty cylinder). In situ single-crystal X-ray diffraction measurements and multilevel computational simulations revealed the importance of pore-surface pockets, which utilize their size and electrostatic potential to smartly recognize the molecular sizes and quadruple moments of gas molecules to control their accessibility to the strongest adsorption sites.

Cage-Confinement Pyrolysis Route to Ultrasmall Tungsten Carbide Nanoparticles for Efficient Electrocatalytic Hydrogen Evolution.

The size-controlled synthesis of ultrasmall metal-based catalysts is of vital importance for chemical conversion technologies. Here, a cage-confinement pyrolysis strategy is presented for the synthesis of ultrasmall tungsten carbide nanoclusters/nanoparticles. An RHO type zeolitic metal azolate framework MAF-6, possessing large nanocages and small apertures, is selected to confine the metal source W(CO)6. High temperature pyrolysis gives tungsten carbide nanoclusters/nanoparticles with sizes ca. 2 nm, which can serve as an excellent electrocatalyst for the hydrogen evolution reaction. In 0.5 M H2SO4, it exhibits very low overpotential of 51 mV at 10 mA cm-2 and Tafel slope of 49 mV per decade, as well as the highest exchange current density of 2.4 mA cm-2 among all tungsten/molybdenum-based catalysts. Moreover, it also shows excellent stability and antiaggregation behavior after long-term electrolytic process.