Development of benzimidazole-based compounds as novel capsid assembly modulators for the treatment of HBV infection.

Hepatitis B virus (HBV) capsid assembly modulators (CAMs) represent a promising therapeutic approach for the treatment of HBV infection. In this study, the hit compound CDI (IC50 = 2.46 ± 0.33 µM) was identified by screening of an in-house compound library. And then novel potent benzimidazole derivatives were designed and synthesized as core assembly modulators, and their antiviral effects were evaluated in vitro and in vivo biological experiments. The results indicated that compound 26f displayed the most optimized modulator of HBV capsid assembly (IC50 = 0.51 ± 0.20 µM, EC50 = 2.24 ± 0.43 µM, CC50 = 84.29 µM) and high selectivity index. Moreover, treatment with compound 26f for 14 days significantly decreased serum levels of HBV DNA levels in the Hydrodynamic-Injection (HDI) mouse model. Therefore, compound 26f could be considered as a promising candidate drug for further development of novel HBV CAMs with the desired potency and safety.

The sources, properties, extraction, biosynthesis, pharmacology, and application of lycopene.

Lycopene is an important pigment with an alkene skeleton from Lycopersicon esculentum, which is also obtained from some red fruits and vegetables. Lycopene is used in the food field with rich functions and serves in the medical field with multiple clinical values because it has dual functions of both medicine and food. It was found that lycopene was mainly isolated by solvent extraction, ultrasonic-assisted extraction, supercritical fluid extraction, high-intensity pulsed electric field-assisted extraction, enzymatic-assisted extraction, and microwave-assisted extraction. Meanwhile, it was also obtained via 2 synthetic pathways: chemical synthesis and biosynthesis. Pharmacological studies revealed that lycopene has anti-oxidant, hypolipidemic, anti-cancer, immunity-enhancing, hepatoprotective, hypoglycemic, cardiovascular-protective, anti-inflammatory, neuroprotective, and osteoporosis-inhibiting effects. The application of lycopene mainly includes food processing, animal breeding, and medical cosmetology fields. It is hoped that this review will provide some useful information and guidance for future study and exploitation of lycopene.

Rationally Engineered hCES2A Near-Infrared Fluorogenic Substrate for Functional Imaging and High-Throughput Inhibitor Screening.

Human carboxylesterase 2A (hCES2A) is an important endoplasmic reticulum (ER)-resident enzyme that is responsible for the hydrolytic metabolism or activation of numerous ester-bearing drugs and environmental toxins. The previously reported hCES2A fluorogenic substrates suffer from limited emission wavelength, low specificity, and poor localization accuracy, thereby greatly limiting the in situ functional imaging of hCES2A and drug discovery. Herein, a rational ligand design strategy was adopted to construct a highly specific near-infrared (NIR) substrate for hCES2A. Following scaffold screening and recognition group optimization, HTCF was identified as a desirable NIR fluorophore with excellent photophysical properties and high ER accumulation ability, while several HTCF esters held a high potential to be good hCES2A substrates. Further investigations revealed that TP-HTCF (the tert-pentyl ester of HTCF) was an ideal substrate with ultrahigh sensitivity, excellent specificity, and a substantial signal-to-noise ratio. Upon the addition of hCES2A, TP-HTCF could be rapidly hydrolyzed to release HTCF, a chemically stable product that emitted bright fluorescent signals at around 670 nm. A TP-HTCF-based biochemical assay was then established for the high-throughput screening of potent and cell-active hCES2A inhibitors from an in-house compound library. Furthermore, TP-HTCF displayed high imaging resolution for imaging hCES2A in living cells as well as mouse liver slices and tumor-xenograft mice. Collectively, this study demonstrates a rational strategy for developing highly specific fluorogenic substrates for an ER-resident target enzyme, while TP-HTCF can act as a practical tool for sensing hCES2A in living systems.

Hippophae rhamnoides L.: A Comprehensive Review on the Botany, Traditional Uses, Phytonutrients, Health Benefits, Quality Markers, and Applications.

Hippophae rhamnoides L. (sea buckthorn), consumed as a food and health supplement worldwide, has rich nutritional and medicinal properties. Different parts of H. rhamnoides L. were used in traditional Chinese medicines for relieving cough, aiding digestion, invigorating blood circulation, and alleviating pain since ancient times. Phytochemical studies revealed a wide variety of phytonutrients, including nutritional components (proteins, minerals, vitamins, etc.) and functional components like flavonoids (1-99), lignans (100-143), volatile oils (144-207), tannins (208-230), terpenoids (231-260), steroids (261-270), organic acids (271-297), and alkaloids (298-305). The pharmacological studies revealed that some crude extracts or compounds of H. rhamnoides L. demonstrated various health benefits, such as anti-inflammatory, antioxidant, hepatoprotective, anticardiovascular disease, anticancer, hypoglycemic, hypolipidemic, neuroprotective, antibacterial activities, and their effective doses and experimental models were summarized and analyzed in this paper. The quality markers (Q-markers) of H. rhamnoides L. were predicted and analyzed based on protobotanical phylogeny, traditional medicinal properties, expanded efficacy, pharmacokinetics and metabolism, and component testability. The applications of H. rhamnoides L. in juice, wine, oil, ferment, and yogurt were also summarized and future prospects were examined in this review. However, the mechanism and structure-activity relationship of some active compounds are not clear, and quality control and potential toxicity are worth further study in the future.

Design, synthesis and biological evaluation of cajanonic acid A analogues as potent PPAR γ antagonists.

Peroxisome proliferator-activated receptor γ (PPAR γ) antagonists are a key instrument of insulin sensitizers since they have the ability to sensitize insulin and can avoid adverse reactions caused by receptor agonist. In this paper, two series of 28 novel Cajanonic acid A (CAA) derivatives were designed and synthesized. The biological activity showed that a novel CAA derivative 9f was identified as a potential PPAR γ antagonist by medicinal chemistry efforts. The results in vitro displayed that compound 9f could improve the PPAR γ antagonist activity (96.2 % / 50.2 % decrease in PPAR γ transactivation at 10 µM / 1 µM, respectively). It also could improve the glucose consumption activity of insulin-resistant HepG2/3T3-L1 cell line (33.27 % / 72.61 % increase in glucose consumption). And in 3 T3-L1 adipocytes, it showed anti-adipogenesis activity (7.04 % increase in oil red staining). Further, in vivo study suggested that compound 9f could improve the oral glucose tolerance in db/db mice. Taken together, derivative 9f served as a promising candidate for anti-diabetic drug discovery and deserve further study.

Design, synthesis, and evaluation of chalcone-Vitamin E-donepezil hybrids as multi-target-directed ligands for the treatment of Alzheimer's disease.

A novel series of chalcone-Vitamin E-donepezil hybrids was designed and developed based on multitarget-directed ligands (MTDLs) strategy for treating Alzheimer's disease (AD). The biological results revealed that compound 17f showed good AChE inhibitory potency (ratAChE IC50 = 0.41 µM; eeAChE IC50 = 1.88 µM). Both the kinetic analysis and docking study revealed that 17f was a mixed type AChE inhibitor. 17f was also a good antioxidant (ORAC = 3.3 eq), selective metal chelator and huMAO-B inhibitor (IC50 = 8.8 µM). Moreover, it showed remarkable inhibition of self- and Cu2+-induced Aß1-42 aggregation with a 78.0 and 93.5% percentage rate at 25 µM, respectively, and disassembled self-induced and Cu2+-induced aggregation of the accumulated Aß1-42 fibrils with 72.3 and 84.5% disaggregation rate, respectively. More importantly, 17f exhibited a good neuroprotective effect on H2O2-induced PC12 cell injury and presented good blood-brain barrier permeability in vitro. Thus, 17f was a promising multi-target-directed ligand for treating AD.

Synthesis and bioevaluation of diaryl urea derivatives as potential antitumor agents for the treatment of human colorectal cancer.

The development of inhibitors targeting the PI3K-Akt-mTOR signaling pathway has been greatly hindered by the on-target AEs, such as hyperglycemia and hepatotoxicities. In this study, a series of diaryl urea derivatives has been designed and synthesized based on clinical candidate gedatolisib (6aa), and most of the newly synthesized derivatives showed kinase inhibitory and antiproliferative activities within nanomolar and submicromolar level, respectively. The terminal l-prolineamide substituted derivative 6 ab showed 8.6-fold more potent PI3Kα inhibitory activity (0.7 nM) and 4.6-fold more potent antiproliferative effect against HCT116 cell lines (0.11 µM) compared with control 6aa. The potential antitumor mechanism and efficacy of 6 ab in HCT116 xenograft models have also been evaluated, and found 6 ab showed comparable in vivo antitumor activity with 6aa. The safety investigations revealed that compound 6 ab exhibited more safer profiles in the selectivity of liver cells (selectivity index: >6.6 vs 1.85) and blood glucose regulation than 6aa. In addition, the in vitro stability assays also indicated our developed compound 6 ab possessed good metabolic stabilities.

Structurally diverse biflavonoids from the fruits of Citrus medica L. var. sarcodactylis Swingle and their hypolipidemic and immunosuppressive activities.

The fruit of Citrus medica L. var. sarcodactylis Swingle is not only used as a traditional medicinal plant, but also served as a delicious food. Six new (3'→7″)-biflavonoids (1-6), and twelve known biflavonoid derivatives (7-18) were isolated and characterized from the fruits of C. medica L. var. sarcodactylis Swingle for the first time. Their structures were determined by extensive and comprehensive analyzing NMR, HR-ESI-MS, UV, and IR spectral data coupled with the data described in the literature. Compounds (1-18) were evaluated for their hypolipidemic activities with Orlistat as the positive control, and assayed for their immunosuppressive activities with Dexamethasone as the positive control, respectively. Among them, compounds (1-3) exhibited moderate inhibition of pancreatic lipase activity by inhibiting 68.56 ± 1.40%, 56.18 ± 1.57%, 53.51 ± 1.59% of pancreatic lipase activities at the concentration of 100 µM, respectively. Compounds (4-6) and 8 showed potent immunosuppressive activities with the IC50 values from 16.83 ± 1.32 to 50.90 ± 1.79 µM. The plausible biogenetic pathway and preliminary structure activity relationship of the selected compounds were scientifically summarized and discussed in this study.

Design, synthesis and evaluation of novel dimethylamino chalcone-O-alkylamines derivatives as potential multifunctional agents against Alzheimer's disease.

A novel series of dimethylamino chalcone-O-alkylamines derivatives was designed and synthesized as multifunctional agents for the treatment of AD. All the target compounds exhibited significant abilities to inhibit and disaggregate Aß aggregation, and acted as potential selective AChE inhibitors, biometal chelators and selective MAO-B inhibitors. Among these compounds, compound TM-6 showed the greatest inhibitory activity against self-induced Aß aggregation (IC50 = 0.88 µM) and well disaggregation ability toward self-induced Aß aggregation (95.1%, 25 µM), the TEM images, molecular docking study and molecular dynamics simulations provided reasonable explanation for its high efficiency, and it was also found to be a remarkable antioxidant (ORAC-FL values of 2.1eq.), the best AChE inhibitor (IC50 = 0.13 µM) and MAO-B inhibitor (IC50 = 1.0 µM), as well as a good neuroprotectant. UV-visual spectrometry and ThT fluorescence assay revealed that compound TM-6 was not only a good biometal chelator by inhibiting Cu2+-induced Aß aggregation (95.3%, 25 µM) but also could disassemble the well-structured Aß fibrils (88.1%, 25 µM). Further, TM-6 could cross the blood-brain barrier (BBB) in vitro. More importantly, compound TM-6 did not show any acute toxicity in mice at doses of up to 1000 mg/kg and improved scopolamine-induced memory impairment. Taken together, these data indicated that TM-6, an excellent balanced multifunctional inhibitor, was a potential lead compound for the treatment of AD.

Isolation and characterization of neolignan derivatives with hepatoprotective and neuroprotective activities from the fruits of Citrus medica L. var. Sarcodactylis Swingle.

The fruit of Citrus medica L. var. sarcodactylis Swingle is a functional food with rich nutrients and medicinal values because of its content of bioactive compounds. A bioactivity-guided chemical investigation from the fruits of C. medica L. var. sarcodactylis Swingle afforded three new benzodioxane neolignans (1-3), three new phenanthrofuran neolignan glycosides (4-6), two new biphenyl-ketone neolignans (7-8), two new 1',7'-bilignan neolignans (9-10), as well as fourteen known neolignan derivatives (11-24), which were isolated and characterized from the fruits of C. medica L. var. sarcodactylis Swingle for the first time. These neolignan derivatives were determined by extensive and comprehensive analyzing NMR, HR-ESI-MS, UV, IR spectral data and compared with the data described in the literature. Among them, compounds 1-3 and 12-13 exhibited moderate hepatoprotective activities to improve the survival rates of HepG2 cells from 46.26 ± 1.90% (APAP, 10 mM) to 67.23 ± 4.25%, 62.87 ± 4.43%, 60.06 ± 6.34%, 56.75 ± 2.30%, 58.35 ± 6.14%, respectively. Additionally, compounds 7-8 and 21-22 displayed moderate neuroprotective activities to raise the survival rates of PC12 cells from 55.30 ± 2.25% to 66.94 ± 3.37%, 70.98 ± 5.05%, 64.64 ± 1.93%, and 62.81 ± 4.11% at 10 µM, respectively. The plausible biogenetic pathway and preliminary structure-activity relationship of the selected compounds were scientifically summarized and discussed in this paper.

Structurally diverse coumarin-homoisoflavonoid derivatives with hepatoprotective activities from the fruits of Cucumis bisexualis.

Cucumis bisexualis is a favorite wild fruit with high nutritional and medicinal values because of its bioactive constituents. Four previously undescribed coumarin-homoisoflavonoid derivatives (1-4), together with seven known coumarin and homoisoflavonoid derivatives (5-11) were isolated from the fruits of C. bisexualis for the first time. All the compounds were elucidated by their extensive and comprehensive spectroscopic data and references. Compounds (1-11) were evaluated for their hepatoprotective activities in HepG2 cells by the acetaminophen (APAP)-induced damage model at 10.0 µM with bicyclol as the positive control. Among them, compounds 1, 3, 5, and 6 showed moderately hepatoprotective activities to improve the HepG2 cell survival rates from 51.68 ± 2.49% (APAP, 10 mM) to 71.55 ± 4.08%, 65.95 ± 4.39%, 60.77 ± 3.44%, 62.94 ± 2.30%, respectively.

Tropolone derivatives with hepatoprotective and antiproliferative activities from the aerial parts of Chenopodium album Linn.

Chenopodium album Linn is used as the traditional Chinese medicine for treating cough, anorexia, piles, dysentery, diarrhea, and kills small worms in China. Nine new tropolones (1-9), and fourteen known tropolone derivatives (10-23) were elucidated by comprehensive spectroscopic data analysis and references from C. album Linn for the first time. Compounds (1-4) and compounds (13-14) displayed notably hepatoprotective activities in intro for lowering AST levels (19.63 ± 2.34 to 29.87 ± 1.27 U•L-1) and ALT levels (15.21 ± 1.18 to 20.29 ± 2.11 U•L-1) in HepG2 cells treated with H2O2. Compounds (8-9) and compounds (15-17) exhibited moderate antiproliferative activities in vitro against the human tumor cell lines with IC50 values ranging from 0.5 ± 0.2 to 15.5 ± 2.7 µM. A preliminary structure activity relationship was summarized and discussed scientifically, which provided new clues to design novel hepatoprotective and antiproliferative drugs based on the tropolone derivatives.

Isolation and characterization of flavonoid derivatives with anti-prostate cancer and hepatoprotective activities from the flowers of Hosta plantaginea (Lam.) Aschers.

ETHNOPHARMACOLOGICAL RELEVANCE: The flower of Hosta plantaginea (Lam.) Aschers (Liliaceae) is a traditional medicinal material in Mongolian medicine for treating sore throat, hoarseness, pulmonary fever, and toxic fever in folk. The present work investigated anti-prostate cancer and hepatoprotective activities of flavonoid derivatives from H. plantaginea (Lam.) Aschers. AIM OF THE STUDY: To isolate and identify the chemicals of H. plantaginea (Lam.) Aschers for anti-prostate cancer and hepatoprotective activities. MATERIALS AND METHODS: Active chemicals were isolated and purified from H. plantaginea (Lam.) Aschers by chromatographic methods, and their structures were established on spectroscopic analysis and references. These compounds were evaluated for their anti-prostate cancer activities using the LNCaP prostate cancer cells, and assayed for their hepatoprotective activities on CCl4-induced injury of human L-O2 cells, respectively. RESULTS: Four new flavonol-lignan heterodimers (1-4), together with nine known flavonoid derivatives (5-13) were isolated from this plant for the first time. Among them, some compounds exhibited moderate anti-prostate cancer and hepatoprotective activities. CONCLUSION: Compounds 1, 2, 5, and 6 showed anti-prostate cancer activities using the LNCaP prostate cancer cells with IC50 values of 17.84, 33.26, 54.13, and 81.55 µg/mL, and compounds 3, 4, 8, and 9 exhibited moderate hepatoprotective activities, respectively. A preliminary structure-activity relation was summarized in this paper.

Structural characterization, neuroprotective and hepatoprotective activities of flavonoids from the bulbs of Heleocharis dulcis.

Chinese water chestnut, the bulb of Heleocharis dulcis, has been widely consumed as fruit or vegetable in China since ancient times. It exhibits health-promoting properties that leads to an extensive study of their active components. Successive chromatography of active fragments of H. dulcis resulted in isolation of five new chalcone-flavonone heterodimers (1-3, 6, 9), four new diverse flavonoids (4, 5, 7, 8), and sixteen known flavonoids derivatives (10-25) were elucidated on the basis of their IR, UV, NMR, MS spectrometry data analysis and references from H. dulcis for the first time. Among these isolates, compounds 4, 7, 9, 12, 13, and 17 showed moderate neuroprotective activity, which increased the cell survival rate from 49.23 ± 3.68% for the model to 67.75 ± 2.75%, 57.83 ± 2.46%, 67.98 ± 2.74%, 58.65 ± 3.43%, 56.14 ± 1.99%, and 56.70 ± 1.38% at 10 µM, respectively. Moreover, compounds 1-3, 15, 16, 18, and 20 were found to moderately improve the HepG2 cell survival rates from 39.53% (APAP, 10 mM) to 45.53-53.44%. The outcome of the study provided crucial information regarding the structural diversity and health benefits of the edible bulbs of H. dulcis.

Hepatoprotective and neuroprotective flavanes from the fruits of Ulmus pumila L. (Ulmaceae).

Phytochemical study of the EtOAc fraction (active extract) of the fruits of Ulmus pumila L. resulted in the isolation of thirteen flavane derivatives, and they were identified by their precise spectral data and literature. All the compounds (1-13) were obtained from the fruits of U. pumila L. for the first time. Meanwhile, the compounds (1-13) were assayed for their hepatoprotective and neuroprotective activities, respectively. Compounds 1, 2, 5, 7 and 8 (10µM) exhibited remarkable hepatoprotective activities, and compounds 9, 10, and 13 showed significant neuroprotective activities with IC50 values of 4.08, 5.34, and 2.02µM, respectively.

Structures and biological evaluation of phenylpropanoid derivatives from Murraya koenigii.

Four new phenylpropanoid derivatives (1-4), together with eleven known analogues (5-15) were isolated and identified by comparison with their references and extensive spectroscopic methods from Murraya koenigii for the first time. Compounds (1-15) were assayed for their inhibitory activities by measuring IL-6-induced STAT3 promoter activities in HepG2 cells, and found compounds 1, 2, 6, and 15 showed inhibitory effects with IC50 values of 11.5, 18.7, 8.9, and 22.7 µM, respectively. The inhibitory activities of compounds (1-15) were screened against NO production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells, and found compounds 3, 4, 9, 11, and 14 exhibited inhibitions against LPS-induced NO production in RAW264.7 macrophages, with IC50 values of 32.7, 7.9, 42.1, 58.9, and 62.4 µM, respectively.

Identification of benzisoquinolinone derivatives with cytotoxicities from the leaves of Portulaca oleracea.

Three new benzisoquinolinones (1-3), together with seven known benzisoquinolinone derivatives (4-10), were isolated from Portulaca oleracea for the first time. The structures of the isolated compounds (1-10) had been elucidated on the basis of extensive spectroscopic methods including ultraviolet, infrared, mass spectrometry, and nuclear magnetic resonance techniques and by comparison with data reported in the references. All isolated compounds were assayed for cytotoxicities against selected human lines in vitro by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Compounds 1, 2, 4, and 7 showed important cytotoxicities against HCT116, MCF-7, U87, and A549 cell lines with IC50 values in the range of 11.62-84.45 µM, which compared with positive control doxorubicin.

Antiangiogenic phenylpropanoid glycosides from Gynura cusimbua.

A new phenylpropanoid glycoside, named α-L-rhamnopyranosyl-(1↔2)-ß-D-[4″-(8E)-7-(3,4-dihydroxyphenyl)-8-propenoate, 1″-O-(7S)-7-(3,4-dihydroxyphenyl)-7-methoxy-ethyl]-glucopyranoside (1), together with nine known compounds (2-10) were isolated from the active fraction (n-Butanol fraction) of Gynura cusimbua for the first time. The known compounds (2-10) were identified as phenylpropanoid glycosides on the basis of extensive spectral data and references. The antiangiogenic activities of compounds (1-10) were evaluated by MTT assay on HUVECs and wild-type zebrafish in vivo model assay. As a result, compounds 1, 6, 7, 8 and 10 exhibited certain antiangiogenic activities.

Carbazole alkaloids with antiangiogenic activities from Clausena sanki.

Two new carbazole alkaloids 1 and 2, and eleven known congeners 3-13 were isolated and identified from Clausena sanki for the first time. Their structures were elucidated on the basis of extensive UV, IR, MS, NMR spectroscopic data and comparison with literatures. The compounds 1-13 were evaluated by MTT assay to determine whether they decreased VEGF-mediated cell proliferation in HUVECs with Axitinib as positive control. Among them, compounds 1, 2, 6, 8, and 13 (µM) exhibited moderate antiangiogenic activities, which inhibited VEGF-induced HUVEC proliferation in vitro with IC50 values of 12.1 (C.I. 8.2-15.2), 58.1 (C.I. 56.3-63.4), 13.7 (C.I. 9.2-15.4), 16.0 (C.I. 9.5-16.4), and 63.2 (C.I. 57.8-65.7) µM, respectively. Moreover, the antiangiogenic activities of compounds 1-13 were evidenced in vivo in the zebrafish embryo model. As a result, compounds 1, 2, 6, 8, and 13 showed effectively suppress angiogenesis. These research results may guide the search for new natural products with antiangiogenic attributes.

Design, synthesis and biological evaluation of phthalimide-alkylamine derivatives as balanced multifunctional cholinesterase and monoamine oxidase-B inhibitors for the treatment of Alzheimer's disease.

A series of novel phthalimide-alkylamine derivatives were synthesized and evaluated as multi-functions inhibitors for the treatment of Alzheimer's disease (AD). The results showed that compound TM-9 could be regarded as a balanced multi-targets active molecule. It exhibited potent and balanced inhibitory activities against ChE and MAO-B (huAChE, huBuChE, and huMAO-B with IC50 values of 1.2µM, 3.8µM and 2.6 µM, respectively) with low selectivity. Both kinetic analysis of AChE inhibition and molecular modeling study suggested that TM-9 binds simultaneously to the catalytic active site and peripheral anionic site of AChE. Interestingly, compound TM-9 abided by Lipinski's rule of five. Furthermore, our investigation proved that TM-9 indicated weak cytotoxicity, and it could cross the blood-brain barrier (BBB) in vitro. The results suggest that compound TM-9, an interesting multi-targeted active molecule, offers an attractive starting point for further lead optimization in the drug-discovery process against Alzheimer's disease.