Two New Compounds Isolated from the Itea omeiensis and Their Anti-oxidant Activities.

Two new compounds (1-2) together with ten known compounds (3-12) were isolated for the first time from the 95 % EtOH extract of aerial parts of Itea omeiensis. Their structures were elucidated based on extensive spectroscopic analyses and comparison with published data. The structure of 1 was further confirmed through single-crystal X-ray diffraction analysis, and circular dichroism (CD) spectrum in combination with acid hydrolysis was employed for the absolute configuration determination of 2. Compound 1 was the first 2-arylbenzo[b]furan with an extra six-membered lactone ring from Itea plants. Anti-oxidant assays indicated that compound 1 possessed significant radical scavenging effects on 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⋅+ ) with IC50 values of 0.14 and 0.06 mg/mL, respectively, which were comparable to the positive control of ascorbic acid. However, no obvious anti-hepatocellular carcinoma activity was observed for compounds 1 and 2.

[A new nor-neolignan compound identified from Itea yunnanensis].

Various separation methods in combination with spectral data analysis, X-ray single crystal diffraction analysis, and litera-ture data comparison were employed to clarify the chemical constituents of Itea yunnanensis. Seven compounds were obtained from I. yunnanensis, which were identified as(S)-3-[1-(4-hydroxyphenyl)propane-2-yl]-4-methoxybenzoate methyl ester(1), iteafuranal B(2), syringaresinol(3), dihydrokaempferol(4), trimethoxybenzene(5), eicosane(6), and nonacosane(7), respectively. Among them, compound 1 was a new nor-neolignan compound named iteanorneoligan A, and the rest of the compounds were identified from I. yunnanensis for the first time. The anti-hepatocellular carcinoma effect of the compound was evaluated based on Sk-hep-1 cells model via MTT assay, and compound 2 showed a significant inhibitory effect on the proliferation of Sk-hep-1 cells with an IC_(50) of 9.4 µmol·L~(-1). The antioxidant capacity was determined via DPPH, ABTS~(·+), and O■ radical scavenging ability, and compound 1 exhibited a significant ABTS~(·+) radical scavenging effect with an IC_(50) of 0.178 mg·mL~(-1).

Qualitative and quantitative method for quality control of Itea ilicifolia based on antioxidant Q-markers.

Itea ilicifolia Oliv is a folk medicine with antioxidant potential. In this study, the fingerprints of 14 batches of I. ilicifolia were established by HPLC with 17 common peaks. The similarities evaluated by Similarity Evaluation System for Chromatographic Fingerprint of Chinese Materia (version 2012) were >0.89. Ten compounds were identified with definite structures by comparing the retention time and characteristic UV spectral pattern with those of reference substances. The antioxidant capacities of 14 batches of I. ilicifolia were evaluated based on O2 ·- , DPPH and ABTS·+ radical scavenging assays in combination with ferric reducing antioxidant power assay. Via multivariate statistical analyses of gray relation analysis, bivariate correlation analysis and partial least squares regression analysis, a study on the spectrum-effect relationship was then performed to screen eight peaks as the antioxidant Q-markers of I. ilicifolia. The contents of representative antioxidant Q-markers (isoorientin, orientin, vitexin, isovitexin and iteafuranal A) in samples were accurately determined to be 0.054-0.118%, 0.034-0.080%, 0.018-0.055%, 0.031-0.091% and 0.033-0.140%, respectively. The qualitative and quantitative analytical method based on Q-markers helps to control the antioxidant quality of I. ilicifolia, which will lay the foundation to promote the rational utilization of I. ilicifolia in curing diseases related to oxidative stress.

Semisynthesis, Biological Evaluation and Molecular Docking Studies of Barbatic Acid Derivatives as Novel Diuretic Candidates.

Barbatic acid, a compound isolated from lichen, has demonstrated a variety of biological activities. In this study, a series of esters based on barbatic acid (6a-q') were designed, synthesized, and evaluated for their diuretic and litholytic activity at a concentration of 100 µmol/L in vitro. All target compounds were characterized using 1H NMR, 13C NMR, and HRMS, and the spatial structure of compound 6w was confirmed using X-ray crystallography. The biological results showed that some derivatives, including 6c, 6b', and 6f', exhibited potent diuretic activity, and 6j and 6m displayed promising litholytic activity. Molecular docking studies further suggested that 6b' had an optimal binding affinity to WNK1 kinases related to diuresis, while 6j could bind to the bicarbonate transporter CaSR through a variety of forces. These findings indicate that some barbatic acid derivatives could be further developed into novel diuretic agents.

Hydroxide-Mediated SNAr Rearrangement for Synthesis of Novel Depside Derivatives Containing Diaryl Ether Skeleton as Antitumor Agents.

A simple and efficient hydroxide-mediated SNAr rearrangement was reported to synthesize new depside derivatives containing the diaryl ether skeleton from the natural product barbatic acid. The prepared compounds were determined using 1H NMR, 13C NMR, HRMS, and X-ray crystallographic analysis and were also screened in vitro for cytotoxicity against three cancer cell lines and one normal cell line. The evaluation results showed that compound 3b possessed the best antiproliferative activity against liver cancer HepG2 cell line and low toxicity, which made it worth further study.

Synthesis of barbacic acid.

A new approach for the synthesis of the active barbatic acid has been achieved in eight steps with 22.3% total yield by using commercially available methyl atratate as starting material. This synthesis provides access to multi-gram quantities of barbatic acid with good purity for reference supplies and further analytical and toxicology investigations.

Carbene-Catalyzed Activation of C-Si Bonds for Chemo- and Enantioselective Cross Brook-Benzoin Reaction.

The first carbene-catalyzed asymmetric chemoselective cross silyl benzoin (Brook-Benzoin) reaction has been developed. Key steps of this reaction involve activation of the carbon-silicon bond of an acylsilane by a chiral N-heterocyclic carbene (NHC) catalyst to form a silyl acyl anion intermediate. These acyl anions then undergo an addition reaction with indole aldehydes in a highly chemo- and enantioselective manner to afford α-silyloxy ketones with excellent optical purities. The reaction mechanism of this cross Brook-Benzoin reaction was investigated through both experimental and computational methods. The chiral α-hydroxy ketone derivatives obtained by this approach show promising, agrochemically interesting activity against harmful plant bacteria.

Effect of Senecio scandens ethanol extract on gut microbiota composition in mice.

The gut microbiota inhabits the animal intestinal tract, and dysbiosis of the gut microbiota may result in disease. Senecio scandens has pharmaceutical antibacterial activities and is regarded as a broad-spectrum antibiotic in traditional Chinese medicine. Extracts of S. scandens are reported to show strong antimicrobial activity, and quercetin significantly decreases some species in the caecal microflora. However, the bactericidal effects of the extracts on the gut microbiota remain obscure. Here, we supplied ethanol extract of S. scandens, which might possibly be used as an alternative for chemical antibiotics, to mice to investigate the state of the intestinal microbiota. Our studies included a control group, low-, moderate-, and high-dose ethanol extract groups, and cefixime capsule group. The ethanol extract groups did not present reduced diversity or differences in the gut microbiota balance. There were significant differences between the ethanol extract and cefixime capsule groups in terms of the gut microbiota. The control and ethanol extract groups contained similar bacteria, which suggested that the ethanol extract has no inhibitory effect on the gut microbiota in vivo. Bifidobacteriales and Lactobacillus acidophilus were significantly increased in the high-dose group. Both secretory immunoglobulin A and mucin 2 concentrations increased as the dose of ethanol extract increased. The functional prediction differences between the control and ethanol extract groups decreased with increasing extract doses, which indicated that the low-dose and high-dose extract treatments might regulate different pathways and functions of the gut microbiota. The results also highlighted the prevention of bacterial drug resistance in the ethanol extract groups.

(±)-Caryopterisines A and B, dimeric monoterpene alkaloids with unprecedented 6/5/5/5/6 pentacyclic rings scaffold from Caryopteris glutinosa.

(±)-Caryopterisines A (1) and B (2) featuring an unprecedented 6/5/5/5/6 pentacyclic rings system were isolated from Caryopteris glutinosa. The structures were determined by spectroscopic and X-ray crystallographic data analyses as well as theoretical calculations. Chiral HPLC resolution of both racemic 1 and 2 afforded their corresponding enantiotropic enantiomers. A plausible biogenesis for 1 and 2 may be originated from Diels-Alder reaction between pyridine-containing oxerine derivatives. The enantiotropic conversion mechanism of the enantiomers was demonstrated by H-D exchange and 18O incorporation studies. Compounds 1 and 2 showed moderate inhibition of estrogen E2 biosynthesis in human ovarian granulosa-like KGN cells. These two alkaloids reduced kynurenine biosynthesis at moderate level via inhibition of indoleamine 2,3-dioxygenase. Alkaloid 2 exhibited moderate inhibition of the release of interleukin-1ß.

Characterization of chemical components with diuretic potential from Pyrrosia petiolosa.

Three compounds with diuretic potential were identified from the 95% ethanol extract of Pyrrosia petiolosa (Christ) Ching. Among them, one was a new benzanilide named petiolide A (1), and the other two were phenolic derivatives barbatic acid (2) and kaempferol (3). Their structures were elucidated based on extensive spectral analyses and comparison with the literature data. The docking experiments of all compounds into the active site of the With-No-Lysine kinase 1 (WNK1) domain demonstrated that kaempferol (3) was the most effective component with diuretic potential for its comparative diuretic effect to that of an orally bioavailable WNK inhibitor WNK463 (docking score -10.99 vs -11.09).[Formula: see text].

Carbene-Catalyzed Enantioselective Aromatic N-Nucleophilic Addition of Heteroarenes to Ketones.

The aromatic nitrogen atoms of heteroarylaldehydes are activated by carbene catalysts to react with ketone electrophiles. Multi-functionalized cyclic N,O-acetal products are afforded in good to excellent yields and optical purities. Our reaction involves the formation of an unprecedented aza-fulvene-type acylazolium intermediate. A broad range of N-heteroaromatic aldehydes and electron-deficient ketone substrates works effectively in this transformation. Several of the chiral N,O-acetal products afforded through this protocol exhibit excellent antibacterial activities against Ralstonia solanacearum (Rs) and are valuable in the development of novel agrichemicals for plant protection.

Carbene-Catalyzed Direct Functionalization of the ß-sp3 -Carbon Atoms of α-Chloroaldehydes.

A direct functionalization of the ß-sp3 carbon atom of α-chloro aldehyde has been developed. The reaction starts with the addition of a carbene catalyst to α-chloroaldehyde to eventually form the homoenolate intermediate. This overall redox-neutral process successfully converts the otherwise inert ß-sp3 -carbon atom of the aldehyde substrate to a nucleophilic carbon atom for asymmetric reactions. This study constitutes the first success in activating α-chloroaldehydes to generate homoenolate intermediates by carbene organic catalysis and shall encourage further explorations in using organic catalysis for transforming inert chemical bonds.

Discovery of 4,6-bis(benzyloxy)-3-phenylbenzofuran as a novel Pin1 inhibitor to suppress hepatocellular carcinoma via upregulating microRNA biogenesis.

Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (Pin1) participates in diverse cancer-associated signaling pathways, playing an oncogenic role in multiple human cancers, including hepatocellular carcinoma (HCC). Our recent works clarify that Pin1 modulates miRNAs biogenesis by interacting with ERK-phosphorylated exportin-5 (XPO5) and changing XPO5 conformation, giving a potential target for HCC treatment. Herein, we discover 4,6-bis(benzyloxy)-3-phenylbenzofuran (TAB29) as a novel Pin1 inhibitor that targets Pin1 PPIase domain. TAB29 potently inhibits Pin1 activity with the IC50 value of 874 nM and displays an excellent selectivity toward Pin1 in vitro. Cell-based biological evaluation reveals that TAB29 significantly suppresses cell proliferation of HCC cells through restoring the nucleus-to-cytoplasm export of XPO5 and upregulating mature miRNAs expression. Collectively, this work provides a promising small molecule lead compound for Pin1 inhibition, highlighting the therapeutic potential of miRNA-based treatment for human cancers.

NHC-Catalyzed Chemoselective Reactions of Enals and Aminobenzaldehydes for Access to Chiral Dihydroquinolines.

An N-heterocyclic carbene (NHC)-catalyzed reaction between α-bromoenals and 2-aminoaldehydes has been developed. Key steps include chemoselective reaction of the NHC catalyst with one of the aldehyde substrates (the bromoenal) to eventually generate an α,ß-unsaturated acylazolium intermediate. Addition of the nitrogen atom of aminoaldehyde to the unsaturated azolium ester intermediate followed by intramolecular aldol reaction, ß-lactone formation, and decarboxylation leads to chiral dihydroquinolines with high optical purity. The dihydroquinoline products, which are quickly prepared by using this method, can be readily transformed into a diverse set of functional molecules such as pyridines and chiral piperidines.

Access to Cyclic ß-Amino Acids by Amine-Catalyzed Enantioselective Addition of the γ-Carbon Atoms of α,ß-Unsaturated Imines to Enals.

Disclosed herein is a new catalytic approach for an efficient access to cyclic ß-amino acids widely found in bioactive small molecules and peptidic foldamers. Our method involves addition of the remote γ-carbon atoms of α,ß-unsaturated imines to enals by iminium organic catalysis. This highly chemo- and stereo-selective reaction affords cyclic ß-amino aldehydes that can be converted to amino acids bearing quaternary stereocenters with exceptional optical purities. Our study demonstrates the unique power of organic catalytic remote carbon reactions in rapid synthesis of functional molecules.

Two cytotoxic 6,7-seco-spiro-lacton-ent-kauranoids from Isodon rubescens.

The present study was performed to investigate the chemical components of the branches and leaves of Isodon rubescens. Two 6,7-seco-spiro-lacton-ent-kauranoids were obtained. Based on the extensive spectroscopic analyses, their structures were elucidated as 6-epi-11-O-acetylangustifolin (1) and 11-O-acetylangustifolin (2), respectively. The structure of 2 was further comfirmed by X-ray crystallography analysis. MTT method was employed to evaluate their cytotoxity against human lung cancer cell lines A549 and leukemia cell lines K562.

Iridoid Glucosides and Diterpenoids from Caryopteris glutinosa.

Five new iridoid glucoside derivatives (1-5), three new diterpenoids (7, 12, and 15), and 11 known compounds were isolated from the aqueous EtOH extract of Caryopteris glutinosa. Cell-based estrogen biosynthesis assays indicated that caryopteriside C (3) and caryopterisoid B (12) promote the biosynthesis of estrogen E2, with EC50 values of 11.1 and 8.0 µM, respectively, in human ovarian granulosa-like KGN cells via upregulating the expression of aromatase.

Antioxidant compounds from ethanol extracts of bamboo (Neosinocalamus affinis) leaves.

Activity-guided fractionation of Neosinocalamus affinis leaves led to obtain two new flavonoids, 4'-O-((7″R,8″S)-8″-guaiacylglyceryl)-pleioside B (9) and apigenin 6-C-ß-d-fucopyranosyl-7-O-ß-d-glucopyranoside (10) along with eight known compounds. Their structures were elucidated on the basis of spectroscopic data (UV, IR, NMR, and MS). Among these 10 compounds, farobin A (4) and isoorientin (7) showed significant antioxidant activity evaluated by 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), superoxide anion and nitric oxide (NO) radical-scavenging assays.

Nitrogen-containing dihydro-ß-agarofuran derivatives from Tripterygium wilfordii.

Thunder god vine, the dried roots of Tripterygium wilfordii, is a widely used traditional Chinese medicine. More than 200 bioactive complex natural products have been isolated from this herb. Inspired by the diversity of chemical structures and bioactivities of the components of this herb, the investigation to mine new chemical entities as potential drug leads led to the identification of 36 nitrogen-containing compounds. Among them, 18 new dihydro-ß-agarofuran alkaloids (tripterygiumines A-L (1-12), M-Q (22-26), and R (33)) were identified from the spectroscopic data and chemical degradation studies. Tripterygiumine Q (26) exhibited immunosuppressive activity against human peripheral mononuclear cells with an IC50 value of 8.67 µM and showed no cytotoxicity, even at 100 µM, indicating that 26 may represent a novel scaffold for the development of new immunosuppressants.

Exploring the hypoglycemic mechanism of chlorogenic acids from Pyrrosia petiolosa (Christ) Ching on type 2 diabetes mellitus based on network pharmacology and transcriptomics strategy.

ETHNOPHARMACOLOGICAL RELEVANCE: Pyrrosia petiolosa (Christ) Ching (YBSW) is a Traditional Chinese medicine rich in chlorogenic acids. It is an important component in many Traditional Chinese medicinal hypoglycemic formulas and is commonly used by the Miao people to treat diabetes with good efficacy. Our previous research has suggested that chlorogenic acids may be the active ingredients in YBSW. AIM OF THE STUDY: To explore the mechanisms underlying the anti-type 2 diabetes mellitus (T2DM) hypoglycemic effects of chlorogenic acids contained in YBSW. MATERIALS AND METHODS: In vivo experiments, hematoxylin-eosin staining (HE) staining, and immunohistochemistry (IHC) were used to determine the effects of chlorogenic acids contained in YBSW in rats. mRNA expression profiling, microarray analysis, and network pharmacology were used to analyze the underlying mechanisms of the effects. Finally, apoptosis and changes in the related pathways were evaluated in vitro using a 3-(4,5-dimethyl-2-thia-zolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay, quantitative real-time polymerase chain reaction, immunofluorescence (IF) assessment, and flow cytometry. RESULTS: After the administration of isochlorogenic acid B, the levels of triglycerides, serum total cholesterol, and fasting blood glucose significantly decreased. HE and IHC staining revealed that isochlorogenic acid B significantly increased insulin expression in islet cells. Using network pharmacology and RNA-seq Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis, we screened the advanced glycation end products-receptor for advanced glycation end products (AGE-RAGE) signaling pathway. We also verified that YBSW and its chlorogenic acid can inhibit apoptosis and downregulate the expression of related mRNA in the AGE-RAGE pathway in RIN-m5f cells. CONCLUSIONS: YBSW exhibits a significant hypoglycemic effect, with chlorogenic acid being an effective component. The therapeutic effect of chlorogenic acids contained in YBSW is mainly realized by promoting insulin secretion and pancreatic tissue repair. Moreover, YBSW substantially mitigates apoptosis via the AGE-RAGE pathway in T2DM.