A Metal-Free Direct Decarboxylative Fluoroacylation of Indole Carboxylic Acids with Fluorinated Acids.

A straightforward preparation of diversified fluorinated indol-3-yl ketones was developed by the direct decarboxylative fluoroacylation of indole carboxylic acids. The reaction could be performed on a gram scale under net conditions. Neither a metal catalyst nor an additive was employed. This methodology featured simple reaction conditions, high efficiency, exclusive selectivity, a broad substrate scope, and easy operation, which allowed it to meet the green chemistry requirement of the modern pharmaceutical industry. Control experiments confirmed that a radical process might be involved in the tandem decarboxylative fluoroacylation sequence.

Force-enhanced sensitive and specific detection of DNA-intercalative agents directly from microorganisms at single-molecule level.

Microorganisms can produce a vast array of bioactive secondary metabolites, including DNA-intercalating agents like actinomycin D, doxorubicin, which hold great potential for cancer chemotherapy. However, discovering novel DNA-intercalating compounds remains challenging due to the limited sensitivity and specificity of conventional activity assays, which require large-scale fermentation and purification. Here, we introduced the single-molecule stretching assay (SMSA) directly to microbial cultures or extracts for discovering DNA-intercalating agents, even in trace amounts of microbial cultures (5 µl). We showed that the unique changes of dsDNA in contour length and overstretching transition enable the specific detection of intercalators from complex samples without the need for extensive purification. Applying force to dsDNA also enhanced the sensitivity by increasing both the binding affinity Ka and the quantity of ligands intercalation, thus allowing the detection of weak intercalators, which are often overlooked using traditional methods. We demonstrated the effectiveness of SMSA, identified two DNA intercalator-producing strains: Streptomyces tanashiensis and Talaromyces funiculosus, and isolated three DNA intercalators: medermycin, kalafungin and ligustrone B. Interestingly, both medermycin and kalafungin, classified as weak DNA intercalators (Ka ∼103 M-1), exhibited potent anti-cancer activity against HCT-116 cancer cells, with IC50 values of 52 ± 6 and 70 ± 7 nM, respectively.

Analgesic Buxus alkaloids with Enhanced Selectivity for the Low-Voltage-Gated Calcium Channel Cav 3.2 over Cav 3.1 through a New Binding Mode.

Low-voltage-gated calcium channels (LVGCCs; Cav 3.1-3.3) represent promising drug targets for epilepsy, pain, and essential tremor. At present, modulators with heightened selectivity for a subtype of LVGCCs are still highly desired. In this study we explored three classes of Buxus alkaloids and identified 9(10/19)abeo-artanes Buxusemine H and Buxusemine L (BXSL) as an unprecedented type of Cav 3.2 inhibitors. Particularly, BXSL exhibited Cav 3.2 inhibition comparable to Z944, a non-subtype-selective LVGCCs inhibitor under clinical trial. While lacking specificity for Cav 3.3, BXSL showed a 30-fold selectivity of Cav 3.2 over Cav 3.1. As compared to several well-known inhibitors, the experimental and computational studies suggested BXSL exhibits a distinct binding mode to Cav 3.2, notably through the essential interaction with serine-1543 in domain III. Furthermore, BXSL showed minimal impact on various recombinant and native nociceptive ion channels, while significantly reducing the excitability of isolated mouse dorsal root ganglion neurons. Animal studies in wild-type and Cav 3.2 knock-out mice revealed that BXSL (5 mg/kg), by inhibiting Cav 3.2, exhibits an analgesic effect equivalent to Z944 (10 mg/kg) or mibefradil (10 mg/kg). Moreover, we proposed a structural rationale for the high selectivity of 9(10/19)abeo-artane-type alkaloids towards Cav 3.2 over Cav 3.1. This study introduces a novel analgesic agent and valuable molecular insight for structure-based innovative Cav 3.2 drug development.

Diterpenoids from Euphorbia fischeriana with Kv1.3 Inhibitory Activity.

Euphorbia diterpenoids possess inhibitory effects of Kv1.3 ion channel, but most of this research has focused on diterpenoids with jatrophane-related or ingenane-related skeletons. In the present study, nine undescribed (1-9) and 16 known (10-25) diterpenoids, based on jatrophane, lathyrane, ingenane, abietane, and atisane skeletons, were identified from the methanol extract of the aerial parts of Euphorbia fischeriana. The structures were established by analysis of the spectroscopic data as well as by single-crystal X-ray diffraction analysis. Among the isolated diterpenoids, macrocyclic jatrophanes and lathyranes exerted Kv1.3 blocking activity. Compound 8 exhibited good selectivity on the inhibition of the Kv 1.3 channel rather than hERG channel, with a selectivity index over 7.0. The selective activity of lathyrane diterpenoids indicates that macrocyclic diterpenoids have the potential to be further investigated as therapeutic agents for the treatment of autoimmune diseases.

Anti-inflammatory lanostane triterpenoids with rearranged spirobi[indene] scaffold and their biogenetically related analogues from Euphorbia maculata.

Phytochemical investigations on the ethanol extract of the whole plant of Euphorbia maculata Linn. Resulted in the identification of 16 lanostane-related triterpenoids, including 11 undescribed ones, namely spiromaculatols A-C (1-3) and euphomaculatoids A-H (4-11). The structural determinations of the previously undescribed ones (1-11) were elucidated based on the interpretation of comprehensive spectroscopic data, quantum chemical calculation, as well as X-ray crystallographic experiments. Spiromaculatols A-C (1-3) possess a rare spirobi [indane] skeleton, which was biosynthetically derived from the 7 (8 â†’ 9)-abeo bond migration of lanostane precursors. The biological activity of compounds 1-3, 5, 7, and 12-13 displayed inhibitory effect on the release of NO in an LPS-activated RAW264.7 cells model. Molecular mechanism study indicated that the most potent spiromaculatol C (3) can reduce the nuclear translocation of NF-κB p65 and decrease the transcriptional expressions of its downstream pro-inflammatory mediators.

Brujavanoids A-U, structurally diverse apotirucallane-type triterpenoids from Brucea javanica and their anti-inflammatory effects.

Extensive phytochemical investigation on the methanol extract of the inflorescences, twigs, and leaves of Brucea javanica led to the isolation and identification of 27 triterpenoids, including 21 previously undescribed ones, named brujavanoids A-U (1-21). Their structures were determined based on comprehensive spectroscopic analysis and single-crystal X-ray diffraction. Of these compounds, brujavanoid A (1) represents the first apotirucallane-type triterpenoid with a novel 19(10 â†’ 9)abeo motif, and brujavanoids B and C (2-3) are the first apotirucallane-type triterpenoids with a rarely occurring 14-hydorxy-15,16-epoxy fragment. All the isolates were evaluated for their anti-inflammatory effect in an LPS-activated RAW264.7 cells model. Furthermore, the most active one, brujavanoid E (5), can suppress the transcriptional expression of typical pro-inflammatory mediators and inhibit the nuclear translocation of NF-κB p65 in the LPS- activated RAW264.7 cells.

Jatrophane Diterpenoids with Kv1.3 Ion Channel Inhibitory Effects from Euphorbia helioscopia.

Chemical investigation of bioactive components from the whole plant of Euphorbia helioscopia resulted in the isolation and identification of 17 new jatrophane diterpenoids, namely, heliojatrone D (1) and helioscopids A-P (2-17), along with 11 known analogues (18-28). The structural elucidation of the new diterpenoids was achieved by the comprehensive analysis of HRESIMS, NMR, and X-ray crystallographic data, as well as using electronic circular dichroism. Structurally, heliojatone D (1) is the fourth natural diterpenoid with a rare bicyclo[8.3.0]tridecane skeleton. The inhibitory effect of the isolated diterpenoids against Kv1.3 ion channels was evaluated in a human embryonic kidney 293 cell model transfected with plasmid encoding Kv1.3, resulting in the identification of a series of potent Kv1.3 ion channel inhibitors, with the most active ones (2 and 15) showing IC50 values of 0.9 µM.

Sesquiterpenoids from Ixeris sonchifolia and their neuroprotective activities.

The phytochemical investigation of the methanol extract of Ixeris sonchifolia led to the isolation and identification of nine analogs, including one new guaiane-type sesquiterpenoid, named ixerinoid A (1). The structure of 1 was determined by extensive analysis of the 1 D and 2 D nuclear magnetic resonance spectroscopic data, as well as quantum chemical calculations. Additionally, all the isolates were tested for their neuroprotective activity using the oxygen-glucose deprivation/reperfusion-induced SH-SY5Y cell injury model. Compounds 3, 5, 6, 8, and 9 displayed remarkable protective effects at concentrations of 1, 5, and 10 µM, respectively.

Diterpenoids with Rearranged 9(10→11)-abeo-10,12-Cyclojatrophane Skeleton and the First (15S)-Jatrophane from Euphorbia helioscopia: Structural Elucidation, Biomimetic Conversion, and Their Immunosuppressive Effects.

Two novel diterpenoids, one with a rearranged trans,trans-fused tricyclo[10.3.0.04,6]pentadecane framework (1) and the other with an unprecedented 15S configuration (2), were isolated from Euphorbia helioscopia. Their structures were elucidated by extensive analysis of HR-ESI-MS, NMR, quantum-chemical calculation, and X-ray crystallographic data. Biosynthetically, 1 has a unique "cyclopropane-shift-like" biogenesis involving an oxa-di-π-methane (ODPM) rearrangement, which inspired us to accomplish the biomimetic conversion of 3 to 1. Moreover, compound 1 displayed a potent immunosuppressive effect by inhibiting Kv1.3 voltage-gated channels.

Stelleranoids A-M, guaiane-type sesquiterpenoids based on [5,7] bicyclic system from Stellera chamaejasme and their cytotoxic activity.

Thirteen previously undescribed guaiane-type sesquiterpenoids based on [5,7] bicyclic system, stelleranoids A-M (1-13), along with six known analogues (14-20), were isolated from the roots of Stellera chamaejasme with chromatographic techniques. Their structures including absolute configurations were determined by HRESIMS and spectroscopic data, quantum chemical calculations, as well as X-ray crystallographic analysis. Cytotoxicity test in three cell lines indicated that compound 14 had relatively stronger cytotoxic effect against MKN-45, SKOV3, and Du145 cell lines with IC50 of 9.8, 17.4 and 7.3 µM, respectively; compounds 3 and 8 displayed moderate cytotoxic effect against MKN-45 and Du145 cell lines with IC50 ranged from 14.5 to 18.8 µM, comparable to those of the positive control. As determined by fluorescent microscopy and flow cytometry in Du145 cell line, compound 14 could promote cell apoptosis and cause cell cycle arrest at the G0/G1 phase, leading to the inhibition of cell proliferation. Further Western blot analysis revealed that this inhibitory effect was accompanied by upregulating pro-apoptosis proteins cleaved-PARP, cleaved-Caspase-9 and tumor suppressor protein p53 while downregulating anti-apoptotic protein Bcl-2 in 14-treated Du145 cells.

Structurally diverse alkaloids from Buxus sempervirens with cardioprotective activity.

Extensive phytochemical study of the methanol extract of twigs and leaves of Buxus sempervirens resulted in the identification of 17 Buxus alkaloids, including 12 new ones, namely buxusemines A-L (1-12). Their structures were delineated by detailed analysis of the HRESIMS and NMR data, as well as quantum chemical NMR calculations. Buxusemine A (1) represents the second Buxus alkaloid with a unique spiro[4.6]undecatriene moiety, buxusemines B-C (2-3) are a rarely occurring class of Buxus alkaloids featured with an additional five-membered ring through the ether or lactone linkage between C-10 and C-23, and buxusemines D-F (4-6) are another rare type of Buxus alkaloids with an epoxy motif. In the assessment of their bioactivities, buxusemine F (6) and buxanoldine (17) displayed more potent protective effects than the positive control cyclovirobuxinum D in the doxorubicin-induced cardiac injury model.

Revealing hypoglycemic and hypolipidemic mechanism of Xiaokeyinshui extract combination on streptozotocin-induced diabetic mice in high sucrose/high fat diet by metabolomics and lipidomics.

Type 2 diabetic mellitus (T2DM), often accompanied by disorders of glucose and lipid metabolism, has troubled hundreds of millions of people. Xiaokeyinshui extract combination (XEC), derived from traditional Chinese medicines formula, has exerted hypoglycemic effects against T2DM. However, its mechanism of metabolic level is still unclear. In this study, a T2DM mice model, induced by a high sucrose/high fat diet combined with low-dose streptozotocin (STZ) injections, was adopted. The biochemical index was determined and a combination of metabolomics and lipidomics analyses of plasma were performed. The results showed that XEC increased secretion of insulin and level of HDL-C, decreased levels of FBG, HbA1c, TC, TG, LDL-C and repaired islet structure in diabetic mice. In addition, the metabolic profiles of plasma were analyzed and 54 potential biomarkers were screened out, mainly including carbohydrates, lipids and amino acids. These potential biomarkers were found to be correlated with the following pathways: galactose metabolism, fructose and mannose metabolism, TCA cycle, arachidonic acid metabolism, glycerolipid metabolism, glycerophospholipid metabolism, sphingolipid metabolism and amino acid metabolism. In conclusion, we speculated that carbohydrate metabolism, lipid metabolism and amino acid metabolism played roles in the therapeutic mechanisms of XEC on T2DM.

Pyrrolizidine alkaloids from the seeds of Scleropyrum wallichianum.

Two new pyrrolizidine alkaloids, sclerwalins A and B (1 and 2), and one known 9-O-E-hydroxysenecioylretronecine (3) were first isolated from the seeds of Scleropyrum wallichianum. Their chemical structures were elucidated by extensive 1 D NMR and 2 D NMR (HSQC, HMBC, COSY, and ROESY), MS and IR spectra. Cytotoxicities of all isolates were evaluated against five human tumor cell lines (HL-60, A-549, SMMC-7721, MCF-7 and SW480).[Formula: see text].

Hypolipidemic and Hepatoprotective Effects of Polysaccharides Extracted from Liriope spicata Var. Prolifera in C57BL/6J Mice with High-Fat Diet-Induced Hyperlipidemia.

In this study, C57BL/6J mice with high-fat diet- (HFD-) induced hyperlipidemia were treated with total Liriope spicata var. prolifera polysaccharides (TLSP: 200, 400, and 800 mg/kg body weight), simvastatin (3 mg/kg body weight), or saline for 8 weeks, respectively. The results showed that TLSP had strong lipid-lowering and hepatoprotective effects on C57BL/6J mice with HFD-induced hyperlipidemia. TLSP administration significantly reduced serum total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) levels and downregulated the expressions of peroxisome proliferator-activated receptor (PPAR)γ and fatty acid synthase (FAS) in the adipose and liver tissues of the mice. TLSP exerted hypolipidemic and hepatoprotective effects by activating lipid/bile acid metabolism via the FXH-SHP/CYP7A1 and SEBP-1c/FAC/ACC signaling pathways. Thus, TLPS is a promising natural polymer with hepatoprotective and hypolipidemic properties.

Data on the optimization of the formula of Xiaokeyinshui extract combination treating diabetes mellitus using uniform experimental design in mice.

This dataset is supplementary to our accepted article in Journal of Ethnopharmacology [1]. Xiaokeyinshui (XKYS) formula, an anti-diabetic formula, was recorded in many ancient Chinese medical books. Xiaokeyinshui extract combination (XEC) originated from this ancient formula, consisting extracts of four herbal drugs, i.e., Coptidis Rhizoma, Liriopes Radix, bitter melon, and Cassiae Semen. In this study, herb extracts were prepared and mixed, producing Xiaokeyinshui extract combination (XEC). The optimized formula of XEC was also investigated via uniform experimental design. Diabetes was induced in Kunming mice, using high-sugar-high-fat diet combined with injection of streptozotocin (STZ) intraperitoneally. Different formulae of XEC were intragastrically administered to diabetic mice for 28 days. Fasting blood glucose (FBG), oral glucose tolerance test (OGTT), hemoglobin A1c (HbA1c), total cholesterol (TC), total triglyceride (TG) were measured to assess the anti-diabetic effects of each formula. Multivariate second degree polynomial model was applied in the fitting of metabolic parameters, and the extremum value of each regression model was calculated using grid algorithm. In addition, an optimized formula of XEC was subjected to validation experiment in mice model. This data could provide basis for a reasonable analysis for the optimization of the formula of XEC.

Xiaokeyinshui extract combination, a berberine-containing agent, exerts anti-diabetic and renal protective effects on rats in multi-target mechanisms.

ETHNOPHARMACOLOGICAL RELEVANCE: Xiaokeyinshui (XKYS) formula, an anti-diabetic formula, was recorded in many ancient Chinese medical books. Xiaokeyinshui extract combination (XEC) originated from this ancient formula, consisting extracts of four herbal drugs, namely, Coptidis Rhizoma, Liriopes Radix, bitter melon, and Cassiae Semen. OBJECTIVE: Therapeutic effects of Xiaokeyinshui extract combination (XEC) were assessed on diabetic rats. MATERIALS AND METHODS: Herb extracts were prepared and mixed, yielding XEC. XEC were intragastrically given at doses of 260, 380 and 500 mg/kg/d to diabetic rats for 60 days. Anti-diabetic effects of XEC were studied, with measurement of body weight, and assessment of both glycemic control and lipid management. Measurement of oxidative stress and inflammatory cytokines were conducted in accordance to protocols of commercial kits. Parameters related to renal functions were also measured. Western blot (WB) analysis was performed to explore the anti-diabetic and renal protective mechanisms of XEC. RESULTS: Compared to diabetic control, XEC exhibited significant effects in both glucose-lowering and lipid management (p < 0.01). Both oxidative stress and inflammatory cytokines were reduced after treatment of XEC for two months. In addition, XEC exhibited renal protective effects. WB analysis of liver tissue demonstrated that XEC achieved anti-diabetic effects through up-regulation of InsRα/IRS-1/PI3K/Akt/GLUT4 signaling pathway and phosphorylation of AMPK. In addition, renal protective effects were also achieved with down-regulation of RAGE and VEGF expressions in kidney. CONCLUSIONS: XEC exerts promising anti-diabetic and renal protective effects on diabetic rats in multi-target mechanisms. XEC could be a satisfying alternative treating T2DM and preventing diabetic nephropathy.

Buxus alkaloid compound destabilizes mutant p53 through inhibition of the HSF1 chaperone axis.

BACKGROUND: P53 is the most frequently mutated gene in most tumour types, and the mutant p53 protein accumulates at high levels in tumours to promote tumour development and progression. Thus, targeting mutant p53 for degradation is one of the therapeutic strategies used to manage tumours that depend on mutant p53 for survival. Buxus alkaloids are traditionally used in the treatment of cardiovascular diseases. We found that triterpenoid alkaloids extracted from Buxus sinica found in the Yunnan Province exhibit anticancer activity by depleting mutant p53 levels in colon cancer cells. PURPOSE: To explore the anticancer mechanism of action of the triterpenoid alkaloid KBA01 compound by targeting mutant p53 degradation. STUDY DESIGN AND METHODS: Different mutant p53 cell lines were used to evaluate the anticancer activity of KBA01. MTT assay, colony formation assay and cell cycle analysis were performed to examine the effect of KBA01 on cancer cell proliferation. Western blotting and qPCR were used to investigate effects of depleting mutant p53, and a ubiquitination assay was used to determine mutant p53 ubiquitin levels after cells were treated with the compound. Co-IP and small interfering RNA assays were used to explore the effects of KBA01 on the interaction of Hsp90 with mutant p53. RESULTS: The triterpenoid alkaloid KBA01 can induce G2/M cell cycle arrest and the apoptosis of HT29 colon cancer cells. KBA01 decreases the stability of DNA contact mutant p53 proteins through the proteasomal pathway with minimal effects on p53 mutant protein conformation. Moreover, KBA01 enhances the interaction of mutant p53 with Hsp70, CHIP and MDM2, and knocking down CHIP and MDM2 stabilizes mutant p53 levels in KBA01-treated cells. In addition, KBA01 disrupts the HSF1-mutant p53-Hsp90 complex and releases mutant p53 to enable its MDM2- and CHIP-mediated degradation. CONCLUSION: Our study reveals that KBA01 depletes mutant p53 protein in a chaperone-assisted ubiquitin/proteasome degradation pathway in cancer cells, providing insights into potential strategies to target mutant p53 tumours.

A new bile acid from the traditional chinese medicine shedan.

A new bile acid tauro-16ß-hydroxy-12α-sulfate-5ß-cholenoic acid (1), along with six known ones (2-7), was isolated from the snake bile. Its planar structure and relative configuration were elucidated based on extensive spectroscopic analyses. Moreover, compound 2 showed inhibitory effect on NO production in RAW 264.7 macrophages at non-cytotoxic concentration (20 µM) with inhibitory rate of 69.7%. [Formula: see text].

Buxaustroines A-N, a Series of 17(13→18)abeo-Cycloartenol Triterpenoidal Alkaloids from Buxus austro-yunnanensis and Their Cardioprotective Activities.

Buxaustroines A-N (1-14), a series of triterpenoidal alkaloids featuring a novel 17(13→18)abeo motif, were obtained from the extract of Buxus austro-yunnanensis. Their structures were assigned based on NMR data analysis and X-ray diffraction crystallography. A putative biosynthetic pathway for one of the alkaloids from a co-isolate 15 is proposed. In the assessment of their bioactivities, some of the compounds displayed protective effects against doxorubicin-induced injury of myocardial cells. Preliminary structure-activity relationship studies of 1-14, which are based on the same skeleton, were conducted.

Network Pharmacology Analysis of Traditional Chinese Medicine Formula Xiao Ke Yin Shui Treating Type 2 Diabetes Mellitus.

Xiao Ke Yin Shui (XKYS) formula is a traditional Chinese medicine formula treating type 2 diabetes mellitus (T2DM). XKYS formula consists of four herbs, i.e., Coptidis rhizoma, Liriopes radix, bitter melon, and Cassiae semen. Herein, the chemical profiles of four herb extracts were investigated, and further analysis of the underlying mechanism of XKYS formula treating T2DM was performed using network pharmacology. The main components were selected for our network-based research. Targets of XKYS formula were mainly collected from two databases, SwissTargetPrediction and Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), and the text-mining method was also implemented. T2DM relating genes and therapeutic targets were collected from five databases. Subsequently, STRING and Cytoscape were employed for the analysis of protein-protein interaction (PPI) networks. Functional annotation and pathway analysis were conducted to investigate the functions and relating pathways of target genes. The content of 12 compounds in the herb extracts was determined. With the analysis of PPI networks, a total of 76 genes were found to be important nodes and could be defined as the main target genes regulated by XKYS formula in the treatment of T2DM and its complications. Components in XKYS formula mainly regulate proteins including protein kinase B (Akt), phosphatidylinositol 3-kinase (PI3K), insulin receptor substrate (IRS), and tumor necrosis factor (TNF). XKYS formula exerts therapeutic effects in a synergetic manner and exhibits antidiabetic effect mainly via reducing insulin resistance. These findings could be guidelines in the further investigation of this formula.