An ingenious technique based on the usage of fluorone-based dye; pyrosin B in prucalopride assay in different matrices through an "on-off" dye native fluorescence probe.

Prucalopride (PCD), is a modern medication approved by the United States in 2018 to alleviate constipation caused by motility issues. PCD demonstrates a strong affinity and selectivity toward the 5-HT4 receptor. The study here introduces a feasible, direct, non-extractive, and affordable pathway for PCD analytical tracking. The fluorimetric study is based on the on-off effect on the emission amplitude of fluorone-based dye (pyrosin B). In a one-pot experiment, the complex between PCD and pyrosin B is formed instantly in an acidic medium. Correlation between decreased pyrosin B emission and PCD concentrations provides a linear calibration plot from 50 to 900 ng/mL. PCD-dye complex system affecting variables were meticulously tuned. The values of the estimated limit of quantitation and limit of detection for the current methodology were 47.5 and 15.7 ng/mL, respectively. Conformity of the strategy validity was achieved by a comprehensive study of the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use criteria. The method was convincingly applied for PCD assay in tablets and content uniformity investigation. Furthermore, PCD tracking in the spiked biological fluid was applied. Finally, the method uses distilled water as dispersing medium which rise accommodation with the green chemistry principle.

Injectable Hydrogels Based on Hyaluronic Acid and Gelatin Combined with Salvianolic Acid B and Vascular Endothelial Growth Factor for Treatment of Traumatic Brain Injury in Mice.

Traumatic brain injury (TBI) leads to structural damage in the brain, and is one of the major causes of disability and death in the world. Herein, we developed a composite injectable hydrogel (HA/Gel) composed of hyaluronic acid (HA) and gelatin (Gel), loaded with vascular endothelial growth factor (VEGF) and salvianolic acid B (SAB) for treatment of TBI. The HA/Gel hydrogels were formed by the coupling of phenol-rich tyramine-modified HA (HA-TA) and tyramine-modified Gel (Gel-TA) catalyzed by horseradish peroxidase (HRP) in the presence of hydrogen peroxide (H2O2). SEM results showed that HA/Gel hydrogel had a porous structure. Rheological test results showed that the hydrogel possessed appropriate rheological properties, and UV spectrophotometry results showed that the hydrogel exhibited excellent SAB release performance. The results of LIVE/DEAD staining, CCK-8 and Phalloidin/DAPI fluorescence staining showed that the HA/Gel hydrogel possessed good cell biocompatibility. Moreover, the hydrogels loaded with SAB and VEGF (HA/Gel/SAB/VEGF) could effectively promote the proliferation of bone marrow mesenchymal stem cells (BMSCs). In addition, the results of H&E staining, CD31 and α-SMA immunofluorescence staining showed that the HA/Gel/SAB/VEGF hydrogel possessed good in vivo biocompatibility and pro-angiogenic ability. Furthermore, immunohistochemical results showed that the injection of HA/Gel/SAB/VEGF hydrogel to the injury site could effectively reduce the volume of defective tissues in traumatic brain injured mice. Our results suggest that the injection of HA/Gel hydrogel loaded with SAB and VEGF might provide a new approach for therapeutic brain tissue repair after traumatic brain injury.

Design, Synthesis, Antibacterial Activity, and Mechanisms of Novel Benzofuran Derivatives Containing Disulfide Moieties.

The unsatisfactory effects of conventional bactericides and antimicrobial resistance have increased the challenges in managing plant diseases caused by bacterial pests. Here, we report the successful design and synthesis of benzofuran derivatives using benzofuran as the core skeleton and splicing the disulfide moieties commonly seen in natural substances with antibacterial properties. Most of our developed benzofurans displayed remarkable antibacterial activities to frequently encountered pathogens, including Xanthomonas oryzae pv oryzae (Xoo), Xanthomonas oryzae pv oryzicola (Xoc), and Xanthomonas axonopodis pv citri (Xac). With the assistance of the three-dimensional quantitative constitutive relationship (3D-QSAR) model, the optimal compound V40 was obtained, which has better in vitro antibacterial activity with EC50 values of 0.28, 0.56, and 10.43 µg/mL against Xoo, Xoc, and Xac, respectively, than those of positive control, TC (66.41, 78.49, and 120.36 µg/mL) and allicin (8.40, 28.22, and 88.04 µg/mL). Combining the results of proteomic analysis and enzyme activity assay allows the antibacterial mechanism of V40 to be preliminarily revealed, suggesting its potential as a versatile bactericide in combating bacterial pests in the future.

α-Glucosidase Inhibitory Components from Garcinia pedunculata Fruits.

From Garcinia pedunculata Roxb. fruits, two undescribed aromatic compounds including a benzofuran and a depsidone derivative, and a new natural product, together with four known compounds were isolated. Through the analysis of spectroscopic data, high resolution mass spectrum and calculated nuclear magnetic resonance, their structures were determined. The α-glucosidase inhibitory activity of the isolates was evaluated. And compound 3 exhibited a moderate inhibitory effect on α-glucosidase. The molecular docking of compound 3 was performed to elucidate the interaction with α-glucosidase.

Morushalunin D, a tri-O-bridged Diels-Alder type adduct from Morus alba var. shalun root cultures and the related precursors.

Three Diels-Alder type adducts (1-3) along with their precursors, including one 2-arylbenzofuran (4) and one stilbene (5), were isolated from the MeOH extract of M. alba var. shalun root cultures. Among them, 1 is a new Diels-Alder type adduct named morushalunin D. The molecular structures of 1-5 were elucidated based on spectroscopic data and comparison with the literatures. Cytotoxic properties of compounds 1-5 were evaluated against murine leukemia P-388 cells. Morushalunin D (1), mulberrofuran T (2), sorocein A (3), moracin M (4), and oxyresveratrol (5) were active, significantly inhibiting the growth of P-388 cells with IC50 values of 0.5, 1.0, 0.6, 2.0, and 3.3 µg/ml, respectively.

Fourteen new 2-benzylbenzofuran glycosides with cardioprotective activity from Heterosmilax yunnanensis.

Fourteen new 2-benzylbenzofuran O-glycosides (1-13, 15) and one new key precursor, diarylacetone (14) were isolated from the roots of Heterosmilax yunnanensis Gagnep, which all have characteristic 2,3,4-O-trisubstituted benzyl. Their structures were elucidated by 1D and 2D NMR, HRESIMS, UV and IR. The isolated compounds were assessed for their cardioprotective activities and compounds 1, 3 and 6 could significantly improve cardiomyocytes viability. Moreover, the mechanistic study revealed that these three compounds could significantly decrease intracellular ROS levels and maintain mitochondrial homeostasis upon hypoxia inducement. Consequently, 1, 3 and 6 might serve as potential lead compounds to prevent myocardial ischemia.

Identification and Optimization of Novel Inhibitors of the Polyketide Synthase 13 Thioesterase Domain with Antitubercular Activity.

There is an urgent need for new tuberculosis (TB) treatments, with novel modes of action, to reduce the incidence/mortality of TB and to combat resistance to current treatments. Through both chemical and genetic methodologies, polyketide synthase 13 (Pks13) has been validated as essential for mycobacterial survival and as an attractive target for Mycobacterium tuberculosis growth inhibitors. A benzofuran series of inhibitors that targeted the Pks13 thioesterase domain, failed to progress to preclinical development due to concerns over cardiotoxicity. Herein, we report the identification of a novel oxadiazole series of Pks13 inhibitors, derived from a high-throughput screening hit and structure-guided optimization. This new series binds in the Pks13 thioesterase domain, with a distinct binding mode compared to the benzofuran series. Through iterative rounds of design, assisted by structural information, lead compounds were identified with improved antitubercular potencies (MIC < 1 µM) and in vitro ADMET profiles.

Verbalide A~F: new phthalide derivatives from the endophytic fungus Preussia sp. CPCC 400972.

There are six new phthalide derivatives Verbalide A ~ F (1-6) together with another known derivative (7) isolated from the endophytic fungus Preussia sp. CPCC 400972. Their structures were established by comprehensive spectroscopic analyses, including NMR and HRESIMS. In addition, compounds 1-7 exhibited excellent inhibitory effect against influenza A virus.

Spiro-Flavonoids in Nature: A Critical Review of Structural Diversity and Bioactivity.

Based on the literature data from 1973 to 2022, this work summarizes reports on spiro-flavonoids with a spiro-carbon at the center of their structure and how this affects their isolation methods, stereochemistry, and biological activity. The review collects 65 unique structures, including spiro-biflavonoids, spiro-triflavonoids, spiro-tetraflavonoids, spiro-flavostilbenoids, and scillascillin-type homoisoflavonoids. Scillascillin-type homoisoflavonoids comprise spiro[bicyclo[4.2.0]octane-7,3'-chromane]-1(6),2,4-trien-4'-one, while the other spiro-flavonoids contain either 2H,2'H-3,3'-spirobi[benzofuran]-2-one or 2'H,3H-2,3'-spirobi[benzofuran]-3-one in the core of their structures. Spiro-flavonoids have been described in more than 40 species of eight families, including Asparagaceae, Cistaceae, Cupressaceae, Fabaceae, Pentaphylacaceae, Pinaceae, Thymelaeaceae, and Vitaceae. The possible biosynthetic pathways for each group of spiro-flavonoids are summarized in detail. Anti-inflammatory and anticancer activities are the most important biological activities of spiro-flavonoids, both in vitro and in vivo. Our work identifies the most promising natural sources, the existing challenges in assigning the stereochemistry of these compounds, and future research perspectives.

Development of a Methodology for Determination of Dioxins and Dioxin-like PCBs in Meconium by Gas Chromatography Coupled to High-Resolution Mass Spectrometry (GC-HRMS).

An analytical strategy was applied to investigate polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dl-PCBs) in newborn meconium samples. The methodology includes extraction by selective pressurized liquid extraction (SPLE), followed by a clean-up multicolumn step. The samples were injected by gas chromatography coupled to a high-resolution mass spectrometer (GC-HRMS). The surrogate recoveries ranged from 68% to 95%, and the average of the limit of quantification (LOQ) ranged from 0.03 to 0.08 pg g-1 wet weight (ww) for PCDD/Fs and 0.2 to 0.88 pg g-1 ww for dl-PCBs. The strategy was applied to 10 samples collected in Valencia (Spain) in 2022. In total, 18 out of 29 analysed congeners were detected in at least one sample, whereas 6 of them were detected in all the samples (OCDD, PCB-123, PCB-118, PCB-105, PCB-167, and PCB-156). The levels for the sum of the 17 congeners of PCDD/Fs and 12 congeners of dl-PCBs in the upper-bound (UB), expressed as picograms of toxic equivalency quantity (TEQ) per gram of ww, ranged from 0.19 to 0.31 pg TEQ g-1 ww.

Exploration of intramolecular charge transfer in para-substituted nitrobenzofurazan: Experimental and theoretical analyses.

The present work aims at exploring the high electrophilic character of 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) toward the morpholine group by an SNAr reaction in acetonitrile or water (thereafter referred to as NBD-Morph). The electron-donating ability of the morpholine causes intra-molecular charge transfer (ICT). In this report, we present a comprehensive study on the optical characteristics using UV-Vis, photoluminescence (cw-PL) and its time-resolved (TR-PL) to determine the properties of the emissive intramolecular charge transfer (ICT) in the NBD-Morph donor-acceptor system. An exhaustive theoretical investigation utilizing the density functional theory (DFT) and its extension TD-DFT methods is an essential complement of experiments to rationalize and understand the molecular structure and related properties. The findings from QTAIM, ELF, and RDG analyses establish that the bonding between morpholine and NBD moieties is of the electrostatic or hydrogen bond type. In addition, the Hirshfeld surfaces have been established to explore the types of interactions. Further, the non-linear optical (NLO) responses of the compound have been examined. The structure-property relationships obtained through the combined experimental and theoretical offer valuable insights for designing efficient NLO material.

Fluorinated Benzofuran and Dihydrobenzofuran as Anti-Inflammatory and Potential Anticancer Agents.

Benzofuran and 2,3-dihydrobenzofuran scaffolds are heterocycles of high value in medicinal chemistry and drug synthesis. Targeting inflammation in cancer associated with chronic inflammation is a promising therapy. In the present study, we investigated the anti-inflammatory effects of fluorinated benzofuran and dihydrobenzofuran derivatives in macrophages and in the air pouch model of inflammation, as well as their anticancer effects in the human colorectal adenocarcinoma cell line HCT116. Six of the nine compounds suppressed lipopolysaccharide-stimulated inflammation by inhibiting the expression of cyclooxygenase-2 and nitric oxide synthase 2 and decreased the secretion of the tested inflammatory mediators. Their IC50 values ranged from 1.2 to 9.04 µM for interleukin-6; from 1.5 to 19.3 µM for Chemokine (C-C) Ligand 2; from 2.4 to 5.2 µM for nitric oxide; and from 1.1 to 20.5 µM for prostaglandin E2. Three novel synthesized benzofuran compounds significantly inhibited cyclooxygenase activity. Most of these compounds showed anti-inflammatory effects in the zymosan-induced air pouch model. Because inflammation may lead to tumorigenesis, we tested the effects of these compounds on the proliferation and apoptosis of HCT116. Two compounds with difluorine, bromine, and ester or carboxylic acid groups inhibited the proliferation by approximately 70%. Inhibition of the expression of the antiapoptotic protein Bcl-2 and concentration-dependent cleavage of PARP-1, as well as DNA fragmentation by approximately 80%, were described. Analysis of the structure-activity relationship suggested that the biological effects of benzofuran derivatives are enhanced in the presence of fluorine, bromine, hydroxyl, and/or carboxyl groups. In conclusion, the designed fluorinated benzofuran and dihydrobenzofuran derivatives are efficient anti-inflammatory agents, with a promising anticancer effect and a combinatory treatment in inflammation and tumorigenesis in cancer microenvironments.

Palladium-Catalyzed Intramolecular Migratory Cycloisomerization of 3-Phenoxy Acrylic Acid Ester via C-O Bond Cleavage and C-O/C-C Bonds Formation for 2,3-Disubstituted Benzofurans Synthesis.

Migratory cycloisomerization using transition metal catalyst is useful for synthesizing substituted heterocyclic compounds. We achieved palladium-catalyzed migratory cycloisomerization of 3-o-alkynylphenoxy acrylic acid ester derivatives to give 2,3-disubstituted benzofurans. Although there are several reports of benzofuran synthesis with palladium-catalyzed migratory cycloisomerization, migratory groups are limited to allyl and propargyl groups. This report is the first example of benzofuran synthesis with palladium-catalyzed cycloisomerization of C(sp2)-O bond cleavage.

Discovery of New Heterocyclic/Benzofuran Hybrids as Potential Anti-Inflammatory Agents: Design, Synthesis, and Evaluation of the Inhibitory Activity of Their Related Inflammatory Factors Based on NF-κB and MAPK Signaling Pathways.

NF-κB and MAPK are classic inflammation signaling pathways which regulate inflammation signal transmission and induce the expression of many inflammatory factors. Based on the potent anti-inflammatory activity of benzofuran and its derivatives, several new heterocyclic/benzofuran hybrids were first designed and synthesized by molecular hybridization. Their structure was confirmed by 1H NMR, 13C NMR, HRMS or X-single crystal diffraction. The anti-inflammatory activity of these new compounds was screened by compounds; compound 5d exhibited an excellent inhibitory effect on the generation of NO (IC50 = 52.23 ± 0.97 µM), and low cytotoxicity (IC50 > 80 µM) against the RAW-264.7 cell lines. To further elucidate the possible anti-inflammatory mechanisms of compound 5d, the hallmark protein expressions of the NF-κB and MAPK pathways were studied in LPS-stimulated RAW264.7 cells. The results indicate that compound 5d not only significantly inhibits the phosphorylation levels of IKKα/IKKß, IKßα, P65, ERK, JNK and P38 in the classic MAPK/NF-κB signaling pathway in a dose-dependent manner, but also down-regulates the secretion of pro-inflammatory factors such as NO, COX-2, TNF-α and IL-6. Further, the in vivo anti-inflammatory activity of compound 5d indicated that it could regulate the involvement of neutrophils, leukocytes and lymphocytes in inflammation processes, and reduce the expression of IL-1ß, TNF-α and IL-6 in serum and tissues. These results strongly suggest that the piperazine/benzofuran hybrid 5d has a good potential for developing an anti-inflammatory lead compound, and the anti-inflammatory mechanism might be related to the NF-κB and MAPK signaling pathways.

Efficacy, Mechanism, and Structure-Activity Relationship of 6-Methoxy Benzofuran Derivatives as a Useful Tool for Senile Osteoporosis.

Most patients with senile osteoporosis (SOP) are severely deficient in bone mass, and treatments using bone resorption inhibitors, such as bisphosphonates, have shown limited efficacy. Small-molecule osteogenesis-promoting drugs are required to improve the treatment for this disease. Previously, we demonstrated that a compound with a benzofuran-like structure promoted bone formation by upregulating BMP-2, and it exhibited a therapeutic effect in SAMP-6 mice, glucocorticoid-induced osteoporosis rats, and ovariectomized rats. In this study, aged C57 and SAMP-6 mice models were used to investigate the therapeutic and preventive effects of compound 125 on SOP. scRNA-seq analysis showed that BMP-2 upregulation is the mechanism through which 125 accelerates bone turnover and increases the proportion of osteoblasts. We evaluated the structure-activity relationship of the candidate drugs and found that the derivative I-9 showed significantly higher efficacy than 125 and teriparatide in the zebrafish osteoporosis model. This study provides a foundation for the development of SOP drugs.

Novel 2,6-disubstituted benzofuran-3-one analogues improve cerebral ischemia/reperfusion injury via neuroprotective and antioxidative effects.

There are no highly effective and safe medicines for clinical treatment of ischemic stroke, although the natural product 3-n-butylphthalide (NBP) has been approved in China for mild and moderate ischemic stroke. To discover more potent anti-cerebral ischemic agents and overcome the low stability by phthalide derivatives, benzofuran-3-one was selected as a core moiety and two types of nitric oxide (NO)-donating groups were incorporated into the structure. In this work, a series of 2,6-disubstituted benzofuran-3-one derivatives were designed and synthesised as NBP analogues, and tested as neuroprotective and antioxidative agents. Compounds 5 (without an NO donor) and 16 (with an NO donor) displayed more potent neuroprotective effects than the established clinical drugs Edaravone and NBP. More importantly, 5 and 16 also exhibited good antioxidative activity without cytotoxicity in rat primary neuronal and PC12 cells. Most active compounds showed good blood-brain barrier permeability in a parallel artificial membrane permeability assay. Furthermore, compound 5 reduced the ischemic infarct area significantly in rats subjected to ischemia/reperfusion injury, downregulated ionised calcium-binding adaptor molecule 1 and glial fibrillary acidic protein in inflammatory cells, and upregulated nerve growth factor.

Electrochemical C(sp3)-H Lactonization of 2-Alkylbenzoic Acids toward Phthalides.

Herein, we report direct electrochemical C(sp3)-H lactonization of 2-alkylbenzoic acids toward phthalides. The reaction provides a wide substrate scope of 2-alkylbenzoic acids bearing primary to tertiary C(sp3)-H bonds by utilizing a graphite anode, dichloromethane (DCM) solvent, hexafluoroisopropanol (HFIP) cosolvent, and n-Bu4NClO4 electrolyte. Our synthetic approach offers a simple, intuitive, and atom-economical protocol to synthesize various phthalides (25 examples, up to 92% yield) and obtain other 5- and 6-membered lactones (10 examples, up to 83% yield).

Redox-neutral rhodium(III)-catalyzed divergent synthesis of tetrasubstituted 1,3-enynes and alkynylated benzofurans.

With the assistance of the acetamido directing group (DG), a rhodium-catalyzed C-H alkenylation/DG migration cascade for the synthesis of tetrasubstituted 1,3-enynes from N-phenoxyacetamides and 1,3-diynes has been achieved in this work. Alternatively, a rhodium-catalyzed [3 + 2] annulation for the synthesis of alkynylated benzofurans from the same set of substrates has also been achieved by simply changing the reaction conditions. This work highlights the tunable divergent synthesis of valuable compounds triggered by C-H activation.

New Benzofuran Oligomers from the Roots of Eupatorium heterophyllum Collected in China.

The chemical constituents of two root samples of Eupatorium heterophyllum DC. collected in Yunnan Province, China, were investigated. Five new oligomeric benzofurans (1-5), nine new benzofuran/dihydrobenzofuran derivatives, and a new thymol analog were isolated, and their structures were determined using extensive spectroscopic techniques, such as 1D and 2D NMR spectroscopy and DFT calculations of the CD spectra. Most of the new compounds, including oligomeric benzofurans (1-5), were obtained from only one of the root samples. Furthermore, this is the first example that produces oligomeric benzofurans in this plant. These results imply that diversification of secondary metabolites in E. heterophyllum is ongoing. Plausible biosynthetic pathways for 1-5 are also proposed.

Advances in Research on Bioactivity, Toxicity, Metabolism, and Pharmacokinetics of Usnic Acid In Vitro and In Vivo.

Lichens are among the most widely distributed plants on earth and have the longest growth cycle. Usnic acid is an abundant characteristic secondary metabolite of lichens and the earliest lichen compound used commercially. It has diverse pharmacological activities, such as anti-inflammatory, antibacterial, antiviral, anticancer, antioxidant, and photoprotective effects, and promotes wound healing. It is widely used in dietary supplements, daily chemical products (fodder, dyes, food, perfumery, and cosmetics), and medicine. However, some studies have found that usnic acid can cause allergic dermatitis and drug-induced liver injury. In this paper, the bioactivity, toxicity, in vivo and in vitro metabolism, and pharmacokinetics of usnic acid were summarized. The aims were to develop and utilize usnic acid and provide reference for its future research.