Licochalcone A: an inducer of cell differentiation and cytotoxic agent from Pogostemon cablin

New natural furfural derivatives from the leaves and stems of Pogostemon cablin

A new furfural derivative, pogoscafuran A (1), a new natural product, HMF levulinate (2), together with four known compounds (3-6) were isolated from an extract of the leaves and stems of Pogostemon cablin (Blanco) Benth. Their structures were elucidated on the basis of extensive spectroscopic analyses and single-crystal X-ray crystallography. Compound 1 was the first example of natural furfural derivative with a unique C5-C1' linkage between a molecule of furfural and 3-methyl-2-cyclopentenone moiety. The plausible biogenetic pathway for the new compound 1 was proposed. All these isolated compounds were tested for their inhibitory effects on the nitric oxide (NO) production induced by lipopolysaccharide in RAW264.7 cells, and only compound 1 exhibited weak inhibitory activity.

Ombuin ameliorates diabetic nephropathy in rats by anti-inflammation and antifibrosis involving Notch 1 and PPAR γ signaling pathways

Diabetic nephropathy (DN) is a common complication of diabetes and it is urgent to develop effective therapies for DN. In this study, high-sucrose and high-fat diet combined with streptozotocin was used to induce DN in rats to observe the effects of natural flavonoid ombuin on renal function, inflammation, and interstitial fibrosis. Immunohistochemistry and western blotting analysis were used to detect protein expression levels. Results showed that ombuin significantly improved renal function and pathological injury, inhibited accumulation of advanced glycation end-products, suppressed the release of inflammatory cytokines, and improved renal interstitial fibrosis in DN rats. Ombuin also significantly downregulated the expressions of transforming growth factor beta1 (TGF-β1), connective tissue growth factor (CTGF), fibronectin (FN), p65, phosphorylated (p)-p65, Cleaved-Notch 1, and hairy and enhancer of split 1 (Hes 1), and upregulated the expression of peroxisome proliferator-activated receptor γ (PPAR γ). When PPAR γ activity was inhibited by T0070907, the effects of ombuin on improving DN were significantly reversed, and the expressions of TGF-β1, FN, CTGF, p-p65, and p65 increased, while the expressions of Cleaved-Notch 1 and Hes 1 were not significantly affected. These results suggest that ombuin may activate PPAR γ to exert anti-inflammatory and antifibrotic effects by inhibiting Notch 1 activity in DN. It is also possible that ombuin acts on these two independent signal pathways synchronously.

Traditional Uses, Phytochemistry, Pharmacology, Quality Control, Industrial Application, Pharmacokinetics and Network Pharmacology of Pogostemon cablin: A Comprehensive Review

Pogostemonis Herba (PH) is the dried aerial parts of Pogostemon cablin (Blanco) Benth, which is mainly distributed and used in Asian countries. PH is an aromatic damp-resolving drug in traditional Chinese medicine (TCM), which is usually used for the treatment of vomiting, chest tension, tiredness, abdominal pain, diarrhea, and headache. In this review, the summary of chemical constituents in the aerial parts, biological activities, history of uses, quality control methods, industrial applications, pharmacokinetics and network pharmacology are reported. By collating the chemical constituents of various parts of PH, a total of 174 components were identified, including 66 terpenes, 6 pyrones, 40 flavonoids, 21 phenylpropanoids, 9 steroids, 4 polysaccharides and 28 others. Pharmacological research has found that PH possesses multi-pharmacological activities, including regulating the gastrointestinal tract, inhibition of pathogenic microorganisms, and anti-inflammation, which provide more scientific interpretation for the clinical usage of PH. In addition, the shortcomings of the current research on PH and the recommendation of future studies on PH are analyzed. We hope this review can provide some insight for further research and applications of PH in future.

Design, Synthesis and Bioactivity Evaluation of Novel Chalcone Derivatives Possessing Tryptophan Moiety with Dual Activities of Anti-cancer and Partially Restoring the Proliferation of Normal Kidney Cells Pre-treated with Cisplatin

BACKGROUND

Chalcone is a broad-spectrum natural product with anti-cancer and anti-inflammatory activities. However, low potency, low selectivity, and serious side effects limit its druggability. L-Tryptophan is an essential precursor molecule of an anti-cancer active substance. Also, the indole moiety inhibits the proliferation of tumor cells by binding to colchicine sites. A decrease in kidney cell activity caused by kidney inflammation is the primary side effect of cancer therapy.

OBJECTIVE

The purpose of this work was to design, synthesize, and perform bioactivity evaluation of novel chalcone derivatives possessing tryptophan moiety with dual activities of anti-cancer and partially restoring the proliferation of normal kidney cells pre-treated with cisplatin.

METHODS

A series of novel chalcone derivatives possessing tryptophan moiety (5a-5g, 6a-6o) were designed, synthesized, and evaluated for anti-cancer activity against four cancer cell lines (gastric (HGC-27), colon (HCT-116), prostate (PC-3), and lung (A549)), and a human normal cell line (gastric mucosal epithelial (GES-1)). The activity of restoring the proliferation of normal kidney cells pre-treated with cisplatin was evaluated by MTT assay. Cell cycle, apoptosis, and apoptosis proteins (Bax and Bcl-2) were used to evaluate the anti-cancer mechanism of the most potent compound. Moreover, a docking study was performed to explain the high anti-cancer activity of 6n. The expressions of TNF-α, IL-6, and MCP-1 were detected by ELISA.

RESULTS

Most of the compounds exhibited high anti-cancer activity against the HGC-27 cell line and exhibited low toxicity against the normal cell line. Based on three rounds of a structure optimization, 6n was discovered as the most potent compound against HGC-27 cells with an IC50 value of 2.02 μM and an SI value of 28.47. Further studies demonstrated that 6n could induce cell cycle arrest at the G2/M phase and the apoptosis of the HGC-27 cell line by reducing the expression of Bcl-2 and improving the expression level of Bax. Molecular docking result displayed 6n bound to the colchicine site. At the same time, 6n also exhibited moderate activity of restoring the proliferation of normal kidney cells pre-treated with cisplatin by reducing the expression of inflammatory substances.

CONCLUSION

Our findings collectively suggested that 6n should be further studied as a potential anti-cancer agent that could partially restore the proliferation of normal kidney cells pre-treated with cisplatin in gastric cancer patients by an anti-inflammatory pathway.

The winding road of the uvaretin class of natural products: from total synthesis to bioactive agent discovery

Herein, we disclose the development of a synthetic route to gain access to the uvaretin class of chalcone natural products. In this, the construction of a small library was achieved, and the collection was evaluated for cytotoxicity and other biological properties. Uvaretin (1) was accessed via a seven-step route in an overall yield of 15.1%. Within this route, the unsaturated enone variant of uvaretin (2), also a natural product, was accessed in a 16.7% yield over six steps. This route provides a nearly three-fold increase in yields of 1 and 2 in comparison to the previous synthetic route accessing them in 5.8% and 3.0% overall yields, respectively. Evaluation of 1 and 2 revealed IC₅₀ values between 2.0 and 5.1 μM in the cancerous cell lines HeLa, U937, A549, and MIA PaCa-2. Screening of the whole chalcone library set led to the discovery of over 30 compounds, within six cancerous cell lines, possessing single digit μM IC₅₀ activity as sole agents. Furthermore, multiple library members were found to possess promising potentiating properties with known chemotherapeutic agents.

Applications of Friedel-Crafts reactions in total synthesis of natural products

Over the years, Friedel-Crafts (FC) reactions have been acknowledged as the most useful and powerful synthetic tools for the construction of a special kind of carbon-carbon bond involving an aromatic moiety. Its stoichiometric and, more recently, its catalytic procedures have extensively been studied. This reaction in recent years has frequently been used as a key step (steps) in the total synthesis of natural products and targeted complex bioactive molecules. In this review, we try to underscore the applications of intermolecular and intramolecular FC reactions in the total syntheses of natural products and complex molecules, exhibiting diverse biological properties.

Antitumour, acute toxicity and molecular modeling studies of 4-(pyridin-4-yl)-6-(thiophen-2-yl) pyrimidin-2(1H)-one against Ehrlich ascites carcinoma and sarcoma-180

In an effort to discover an effective and selective antitumour agent, synthesis and anti-cancer potential of 4-(pyridin-4-yl)-6-(thiophen-2-yl) pyrimidin-2(1H)-one (SK-25), which has been reported earlier by us with significant cytotoxicity towards MiaPaCa-2 malignant cells, with an IC₅₀ value of 1.95 μM and was found to instigate apoptosis. In the present study, the antitumour efficacy of SK-25 was investigated on Ehrlich ascites tumour (EAT, solid), Sarcoma 180 (solid) tumour and Ehrlich ascites carcinoma. The compound was found to inhibit tumour development by 94.71% in Ehrlich ascites carcinoma (EAC), 59.06% in Ehrlich tumour (ET, solid) and 45.68% in Sarcoma-180 (solid) at 30 mg/kg dose. Additionally, SK-25 was established to be non-toxic at a maximum tolerated dose of 1000 mg/kg in acute oral toxicity in Swiss-albino mice. Computer-based predictions also show that the compounds could have an interesting DMPK profile since all 51 computed physicochemical parameters fall within the recommended range for 95% of known drugs. The current study provides insight for further investigation of the antitumour potential of the molecule.

Design and Evaluation of Licochalcone A Derivatives as Anticancer Agents

New derivatives of licochalcone A were synthesized and evaluated for their potential anticancer activities. Compounds 6 (( E)-N-(4-(3-(5-bromo-4-hydroxy-2-methoxy phenyl) acryloyl) phenyl)-4-isopropylbenzamide) and 8 (1-(3-dimethylamino-phenyl)-3-(2-trifluoromethyl-phenyl)-propenone) showed potent activity against the screened cancer cell lines with that of compound 6 ranging from 6.9 ± 0.2 μM to 22.9 ± 3.1 μM, and that of compound 8 from 4.2 ± 0.5 μM to 11.8 ± 0.7 μM. Both compounds showed stronger cytotoxicity than that of licochalcone A. These two candidates have very different substituents and could be considered as promising lead compounds for further development of potent anticancer agents.

Antipsychotic dopamine receptor antagonists, cancer, and cancer stem cells

Cancer is one of the deadliest diseases in the world. Despite extensive studies, treating metastatic cancers remains challenging. Years of research have linked a rare set of cells known as cancer stem cells (CSCs) to drug resistance, leading to the suggestion that eradication of CSCs might be an effective therapeutic strategy. However, few drug candidates are active against CSCs. New drug discovery is often a lengthy process. Drug screening has been advantageous in identifying drug candidates. Current understanding of cancer biology has revealed various clues to target cancer from different points of view. Many studies have found dopamine receptors (DRs) in various cancers. Therefore, DR antagonists have attracted a lot of attention in cancer research. Recently, a group of antipsychotic DR antagonists has been demonstrated to possess remarkable abilities to restrain and sensitize CSCs to existing chemotherapeutics by a process called differentiation approach. In this review, we will describe current aspects of CSC-targeting therapeutics, antipsychotic DR antagonists, and their extraordinary abilities to fight cancer.

2,4-Diarylpyrano[3,2-c]chromen-5(4H)-ones as Antiproliferative Agents

In the present study, a series of 2,4-diarylpyrano[3,2-c]chromen-5(4H)-ones were synthesised and evaluated as antiproliferative agents. The compounds were evaluated against a panel of human cancer cell lines. CH-1 exhibited significant cytoxicity against HCT 116 cell lines with an IC50 value of 1.4 and 4.3 µM against "MiaPaCa-2" cell lines. The compound CH-1 was found to induce apoptosis as evidenced by phase contrast microscopy, Hoechst 33258 staining and mitochondrial membrane potential (MMP) loss. The cell phase distribution studies indicated that the apoptotic population increased from 10.22% in the control sample to 57.19% in a sample treated with 20 µM compound CH-1.

Survey of the genome of Pogostemon cablin provides insights into its evolutionary history and sesquiterpenoid biosynthesis

Pogostemon cablin (Blanco) Benth. (Patchouli) is an important traditional Chinese medicinal plant that has both essential oil value and a broad range of therapeutic effects. Here we report the first de novo assembled 1.15-Gb draft genome sequence for P. cablin from next-generation sequencing technology. Our assembly, with a misassembly rate of <4 bp per 100 kb, is ~73% of the predicted genome size (1.57 Gb). Analysis of whole-genome sequences identified 3,147,333 heterozygous single-nucleotide polymorphisms and 490,407 insertions and deletions, giving an estimated heterozygosity rate of 0.274%. A comprehensive annotation pipeline indicated that repetitive sequences make up 58.55% of the assemblies, and that there are estimated 45,020 genes. Comparative genomics analysis showed that the Phrymaceae and Lamiaceae family split ~62.80 Mya, and the divergence between patchouli and sesame occurred ~52.42 Mya, implying a potentially shared recent whole-genome duplication event. Analysis of gene homologs involved in sesquiterpenoid biosynthesis showed that patchouli contains key genes involved in more sesquiterpenoid types and has more copies of genes for each sesquiterpenoid type than several other related plant species. The patchouli genome will facilitate future research on secondary metabolic pathways and their regulation as well as potential selective breeding of patchouli.

Design, synthesis and biological evaluation of novel benzimidazole-2-substituted phenyl or pyridine propyl ketene derivatives as antitumour agents

A series of novel benzimidazole-2-subsituted phenyl or pyridine propyl ketene derivatives were designed and synthesized. The biological activities of these derivatives were then evaluated as potential antitumour agents. These compounds were assayed for growth-inhibitory activity against HCT116, MCF-7 and HepG2 cell lines in vitro. The IC50 values of compounds A1 and A7 against the cancer cells were 0.06-3.64 μM and 0.04-9.80 μM, respectively. Their antiproliferative activities were significantly better than that of 5-Fluorouracil (IC50: 56.96-174.50 μM) and were close to that of Paclitaxel (IC50: 0.026-1.53 μM). The activity of these derivatives was over 100 times more effective than other reported structures of chalcone analogues (licochalcone A). A preliminary mechanistic study suggested that these compounds inhibit p53-MDM2 binding. Compounds A1, A7 and A9 effectively inhibited tumour growth in BALB/c mice with colon carcinoma HCT116 cells. The group administered 200 mg/kg of compound A7 showed a 74.6% tumour growth inhibition with no signs of toxicity at high doses that was similar to the inhibition achieved with the 12.5 mg/kg irinotecan positive control (70.2%). Therefore, this class of benzimidazole-2-subsituted phenyl or pyridine propyl ketene derivatives represents a promising lead structure for the development of possible p53-MDM2 inhibitors as new antitumour agents.

Licochalcone C induces apoptosis via B-cell lymphoma 2 family proteins in T24 cells

The current study investigated the mechanisms by which licochalcone C induces apoptosis of T24 human malignant bladder cancer cells. Cell viability was evaluated using an MTT assay. Apoptosis was investigated using a morphological assay, flow cytometry and a caspase‑3 activity assay. Alterations in the gene expression levels of Bcl‑2 family members were measured by semi‑quantitative reverse transcription‑polymerase chain reaction assays. The protein levels of pro‑caspase‑3 and cleaved poly(ADP ribose) polymerase were measured using western blotting. The results indicated that licochalcone C induced T24 cell apoptosis in a concentration‑dependent manner. Licochalcone C treatment reduced the levels of the anti‑apoptotic mRNAs (Bcl‑2, Bcl‑w and Bcl‑XL) and increased expression of the pro‑apoptotic mRNAs (Bax and Bim). The Bcl‑2 family inhibitor (ABT‑737) reduced apoptosis induced by licochalcone C in T24 cells. The current study demonstrated that licochalcone C may be a potential adjuvant therapeutic agent for bladder cancer.

A Comprehensive Review on the Phytochemical Constituents and Pharmacological Activities of Pogostemon cablin Benth.: An Aromatic Medicinal Plant of Industrial Importance

Pogostemon cablin Benth. (patchouli) is an important herb which possesses many therapeutic properties and is widely used in the fragrance industries. In traditional medicinal practices, it is used to treat colds, headaches, fever, nausea, vomiting, diarrhea, abdominal pain, insect and snake bites. In aromatherapy, patchouli oil is used to relieve depression, stress, calm nerves, control appetite and to improve sexual interest. Till now more than 140 compounds, including terpenoids, phytosterols, flavonoids, organic acids, lignins, alkaloids, glycosides, alcohols, aldehydes have been isolated and identified from patchouli. The main phytochemical compounds are patchouli alcohol, α-patchoulene, β-patchoulene, α-bulnesene, seychellene, norpatchoulenol, pogostone, eugenol and pogostol. Modern studies have revealed several biological activities such as antioxidant, analgesic, anti-inflammatory, antiplatelet, antithrombotic, aphrodisiac, antidepressant, antimutagenic, antiemetic, fibrinolytic and cytotoxic activities. However, some of the traditional uses need to be verified and may require standardizing and authenticating the bioactivity of purified compounds through scientific methods. The aim of the present review is to provide comprehensive knowledge on the phytochemistry and pharmacological activities of essential oil and different plant extracts of patchouli based on the available scientific literature. This information will provide a potential guide in exploring the use of main active compounds of patchouli in various medical fields.

A new antibacterial octaketide and cytotoxic phenylethanoid glycosides from Pogostemon cablin (Blanco) Benth

A new octaketide, named cytosporone V (1), and two other known phenylethanoid glycosides (2-3), were isolated from the aerial parts of Pogostemon cablin (Blanco) Benth. The structure of 1 was elucidated by a combination of extensive spectroscopic analyses, including extensive 2D NMR and HR-MS. Compounds 1-3 displayed weak antibacterial activity against two gram-positive bacteria, Bacillus subtilis and Staphylococcus aureus. All isolates were also evaluated for their antiproliferative activities against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15). Compounds 2 and 3 showed significant cytotoxicity against A549, SK-OV-3, SK-MEL-2, and HCT-15 cell lines with IC50 values ranging from 2.73 to 9.52 μM.

Chalcone based azacarboline analogues as novel antitubulin agents: design, synthesis, biological evaluation and molecular modelling studies

The present study involves the design of a series of 3-aryl-9-acetyl-pyridazino[3,4-b]indoles as constrained chalcone analogues. A retrosynthetic route was proposed for the synthesis of target compounds. All the synthesized compounds were evaluated for in-vitro cytotoxicity against THP-1, COLO-205, HCT-116 and A-549 human cancer cell lines. The results indicated that 2a, 3a, 5a and 6a possessed significant cytotoxic potential with an IC50 value ranging from 1.13 to 5.76 μM. Structure activity relationship revealed that the nature of both Ring A and Ring B influences the activity. Substitution of methoxy groups on the phenyl ring (Ring A) and unsubstituted phenyl ring (Ring B) were found to be the preferred structural features. The most potent compound 2a was further tested for tubulin inhibition. Compound 2a was found to significantly inhibit the tubulin polymerization (IC50 value - 2.41 μM against THP-1). Compound 2a also caused disruption of microtubule assembly as evidenced by Immunoflourescence technique. The significant cytotoxicity and tubulin inhibition by 2a was rationalized by molecular modelling studies. The most potent structure was docked at colchicine binding site (PDB ID-1SA0) and was found to be stabilized in the cavity via various hydrophobic and hydrogen bonding interactions.

Synthesis, biological evaluation and molecular docking studies of trans-indole-3-acrylamide derivatives, a new class of tubulin polymerization inhibitors

In this study, we synthesized a series of trans-indole-3-acrylamide derivatives (3a-k) and investigated their activity for inhibition of cell proliferation against five human cancer cell lines (HeLa, MCF7, MDA-MB-231, Raji and HL-60) by MTT assay. Compound 3e showed significant antiproliferative activity against both the Raji and HL-60 cell lines with IC50 values of 9.5 and 5.1 μM, respectively. Compound 3e also exhibited moderate inhibitory activity on tubulin polymerization (IC50=17 μM). Flow cytometric analysis of cultured cells treated with 3e also demonstrated that the compound caused cell cycle arrest at the G2/M phase in HL-60 and HeLa cells. Moreover, 3e, the most active compound, caused an apoptotic cell death through the activation of caspase-3. Docking simulations suggested that 3e binds to the colchicine site of tubulin.

Synthesis, biological evaluation, and molecular docking studies of novel chalcone oxime derivatives as potential tubulin polymerization inhibitors

Compounds of novel chalcone oxime derivatives containing different substituent groups were designed, synthesized and evaluated for the inhibitory activity against tubulin polymerization and cancer cell inhibitory activity.

Concise synthesis of licochalcone C and its regioisomer, licochalcone H

Licochalone C (7a) is a retrochalcone isolated from Glycyrrhiza inflata, which shows potent antioxidant properties and inhibition of bacterial growth and cellular respiration. Biological studies have suggested that licochalcone C attenuates the lipopolysaccharide and interferon-gamma induced inflammatory response by decreasing the expression and activity of inducible nitric oxide synthase and modulating the antioxidant network activity of superoxide dismutase, catalase, and glutathione peroxidase activity. Licochalcone C also inhibits NADH-cytochrome C reductase in the membrane fraction of Micrococcus luteus. Since pharmacological activity studies of licochalcone C are ongoing and the yield of the compound is poor from natural product, we report a concise four step synthesis of licochalcone C (7a) and its regioisomer, tentatively called licochalcone H (7b), by employing acid-mediated Claisen-Schmidt condensation as a key step with 6 and 20 % overall yield, respectively.

Four new sesquiterpenes from the stems of Pogostemon cablin

Four new sesquiterpenes (1-4), together with four known compounds (5-8), were isolated from the stems of Pogostemon cablin (Blanco.) Benth. Their chemical structures were elucidated by means of spectroscopic methods, including 1D and 2D NMR, HRESIMS, IR, and UV. Hepatoprotective activities of these compounds were investigated, by studying the protective effect on HL-7702 cellular injury induced by dl-galactosamine.

Efficient Knoevenagel Condensation Reactions Catalyzed by Activated Gel Zirconium(IV) Oxide

The condensation reaction has been carried out very conveniently to obtain the corresponding substituted 2,2′-(arylmethylene)bis(3-hydroxy-5,5-dimethylcyclohex-2-enone) in excellent yields. The reaction conditions are very mild and applicable to various aldehydes as well as active methylene compounds.

Antioxidant and anti-inflammatory activities of selected Chinese medicinal plants and their relation with antioxidant content

BACKGROUND

The main aim of this study is to evaluate the antioxidant and anti-inflammatory properties of forty four traditional Chinese medicinal herbal extracts and to examine these activities in relation to their antioxidant content.

METHODS

The antioxidant activities were investigated using DPPH radical scavenging method and yeast model. The anti-inflammatory properties of the herbal extracts were evaluated by measuring their ability to inhibit the production of nitric oxide and TNF-α in RAW 264.7 macrophages activated by LPS and IFN- γ, respectively. The cytotoxic effects of the herbal extracts were determined by Alomar Blue assay by measuring cell viability. In order to understand the variation of antioxidant activities of herbal extracts with their antioxidant contents, the total phenolics, total flavonoids and trace metal (Mg, Mn, Cu, Zn, Se and Mo) quantities were estimated and a correlation analysis was carried out.

RESULTS

Results of this study show that significant levels of phenolics, flavonoids and trace metal contents were found in Ligustrum lucidum, Paeonia suffuticosa, Salvia miltiorrhiza, Sanguisorba officinalis, Spatholobus suberectus, Tussilago farfara and Uncaria rhyncophylla, which correlated well with their antioxidant and anti-inflammatory activities. Some of the plants displayed high antioxidant and anti-inflammatory activities but contained low levels of phenolics and flavonoids. Interestingly, these plants contained significant levels of trace metals (such as Zn, Mg and Se) which are likely to be responsible for their activities.

CONCLUSIONS

The results indicate that the phenolics, flavonoids and trace metals play an important role in the antioxidant activities of medicinal plants. Many of the plants studied here have been identified as potential sources of new antioxidant compounds.

Synthesis, biological evaluation, and molecular docking studies of cinnamic acyl 1,3,4-thiadiazole amide derivatives as novel antitubulin agents

A series of cinnamic acyl 1,3,4-thiadiazole amide derivatives (6a-10e) have been designed and synthesized, and their biological activities were also evaluated as potential antiproliferation and tubulin polymerization inhibitors. Among all the compounds, 10e showed the most potent activity in vitro, which inhibited the growth of MCF-7 and A549 cell lines with IC(50) values of 0.28 and 0.52μg/mL, respectively. Compound 10e also exhibited significant tubulin polymerization inhibitory activity (IC(50)=1.16μg/mL). Docking simulation was performed to insert compound 10e into the crystal structure of tubulin at colchicine binding site to determine the probable binding model. Based on the preliminary results, compound 10e with potent inhibitory activity in tumor growth may be a potential anticancer agent.

Design, synthesis and cytotoxicity of novel chalcone analogs derived from 1-cyclohexylpyrrolidin-2-one and 2,3-dihydrobenzo[f]chromen-1-one

Two divergent series of novel chalcone analogs, one derived from 1-cyclohexylpyrrolidin-2-one and the other derived from 1-benzo[f]chromanone, were designed, synthesized and evaluated for cytotoxicity against two murine cancer cell lines. Two 1-benzo[f]chromanone analogs, 4g and 4j yielded moderate toxicity against both melanoma B16 and lymphoma L1210 cell lines with IC(50) values between the range of 5 and 6 µM. With an IC(50) value of 3.4 µM, compound 4g was also active against human MDA-MB-435 melanoma cells. X-ray structures of the β-hydroxy ketone product (4a) and the α,β-unsaturated ketone (4h) were collected, and confirm the syn-configuration between the carbonyl moiety and the β-vinylic proton in 4h. X-ray structures of two 1-cyclohexylpyrrolidin-2-one derivatives were also obtained, and both showed an E-configuration for the double bond.

Design, synthesis, and cytotoxicity of novel 3-arylidenones derived from alicyclic ketones

Forty-four novel chalcone-inspired analogs having a 3-aryl-2-propenoyl moiety derived from alicyclic ketones were designed, synthesized, and investigated for cytotoxicity against murine B16 and L1210 cancer cell lines. The analogs belong to four structurally divergent series, three of which (series g, h, and i) contain differently substituted cyclopentanone units and the fourth (series j) contains a 3,3-dimethyl-4-piperidinone moiety. Of these, the analogs in series j showed potential cytotoxic activity against murine B16 (melanoma) and L1210 (lymphoma) cells. The most active compounds 5j, 11j, 15j, and 12h produced IC(50) values from 4.4 to 15 μm against both cell lines. A single-crystal X-ray structure analysis and molecular modeling studies confirmed that these chalcones have an E-geometry about the alkene bond and possess a slightly 'twisted' conformation similar to that of combretastatin A-4. At a concentration of 30 μm, compounds 5j, 11j, and 15j did not cause microtubule depolymerization in cells, suggesting that they have a different mechanism of action.

Evaluation of cytotoxicity and genotoxicity of some Philippine medicinal plants

The genotoxicity and toxicity of ethnomedicinal Philippine plants, which include Cassia fistula, Derris elliptica, Ficus elastica, Gliciridia sepium, Michelia alba, Morus alba, Pogostemon cablin and Ricinus communis, were tested using the Vitotox assay. The plants are used traditionally to treat several disorders like diabetes, weakness, menorrhagia, headache, toothache and rheumatism. The dried leaves were homogenized for overnight soaking in methanol at room temperature. The resulting alcoholic extracts were filtered and concentrated in vacuo and tested for their genotoxicity and cytotoxicity using Vitotox®. Results showed that the medicinal plants that were tested are not genotoxic nor cytotoxic, except for R. communis and P. cablin, which showed toxicity at high doses (low dilutions) in the absence of S9.

Synthesis, biological evaluation, and molecular modeling of cinnamic acyl sulfonamide derivatives as novel antitubulin agents

A series of novel cinnamic acyl sulfonamide derivatives (9a-16e) have been designed and synthesized and their biological activities were also evaluated as potential tubulin polymerization inhibitors. Among all the compounds, 10c showed the most potent growth inhibitory activity against B16-F10 cancer cell line in vitro, with an IC(50) value of 0.8μg/mL. Docking simulation was performed to insert compound 10c into the crystal structure of tubulin at colchicine binding site to determine the probable binding model. Based on the preliminary results, compound 10c with potent inhibitory activity in tumor growth may be a potential anticancer agent.

Anti-inflammatory effect of patchouli alcohol isolated from Pogostemonis Herba in LPS-stimulated RAW264.7 macrophages

Pogostemonis Herba has long been used in traditional Chinese medicine for the treatment of inflammation-related disorders. Patchouli alcohol (PA) isolated from Pogostemonis Herba is a tricyclic sesquiterpene that is known to exert a variety of pharmacological activities. The present study aimed to investigate the anti-inflammatory effect of PA on lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Pre-treatment with PA at concentrations of 10, 20 or 40 μM dose-dependently decreased the production of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, nitric oxide (NO) and prostaglandin E(2) in LPS-stimulated RAW264.7 cells. In addition, PA treatment also reversed the increased mRNA expression of TNF-α, IL-1β, IL-6, inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 caused by LPS in RAW264.7 cells. These results indicate that PA is an important anti-inflammatory constituent of Pogostemonis Herba and that its anti-inflammatory effect may be mediated, at least in part, by down-regulation of the mRNA expression of a panel of inflammatory mediators, such as TNF-α, IL-1β, IL-6, iNOS and COX-2.

Synthesis, biological evaluation, and molecular docking studies of resveratrol derivatives possessing chalcone moiety as potential antitubulin agents

Twenty-three resveratrol derivatives possessing chalcone moiety were synthesized and characterized, and their biological activities were also evaluated as potential antiproliferation and tubulin polymerization inhibitors. Compound C19 exhibited the most potent activity in vitro, which inhibited the growth of HepG2, B16-F10, and A549 cell lines with IC(50) values of 0.2, 0.1, and 1.4 μg/mL, respectively. Compound C19 also exhibited significant tubulin polymerization inhibitory activity (IC(50)=2.6 μg/mL). Docking simulation was performed to position compound C19 into the tubulin-colchicine binding site to determine the probable binding mode.

Analgesic and Anti-Inflammatory Activities of the Methanol Extract from Pogostemon cablin

Pogostemon cablin (PC) is a herbal medicine traditionally applied to treat not only common cold, nausea and diarrhea but also headache and fever. The aim of this study was to investigate the analgesic and anti-inflammatory properties of standardized PC methanol extract (PCMeOH) in vivo. Investigations were performed in mice with two analgesic models. One was acetic acid-induced writhing response and the other formalin-induced paw licking. The anti-inflammatory effect was tested by λ-carrageenan (Carr)-induced mice paw edema. These analgesic experimental results indicated that PCMeOH (1.0 g/kg) decreased the acetic acid-induced writhing responses and PCMeOH (0.5 and 1.0 g/kg) decreased the licking time in the second phase of the formalin test. Moreover, Carr-induced paw edema inflammation was significantly reduced in a dose-dependent manner when PCMeOH (0.5 and 1.0 g/kg) was administered 3 and 4 h after the Carr injection. Mechanistic studies showed that PCMeOH decreased the levels of malondialdehyde in the edema paw by increasing the activities of anti-oxidant enzymes, such as superoxide dismutase, glutathione peroxidase and glutathione reductase, in the liver and decreasing the cyclooxygenase 2 and tumor necrosis factor-α activities in the edema paw. This study has demonstrated the analgesic and anti-inflammatory effects of PCMeOH, thus verifying its popular use in traditional medicine.

Synthesis and anti breast cancer activity of biphenyl based chalcones

A series of (2E,2'E)-1,1'-(3-hydroxy-5-methylbiphenyl-2,6-diyl)-bis(3-pheylprop-2-ene-1-ones (5-33) were prepared by the reaction of 1,3-diacetyl biphenyls (1-4) with different aldehydes in presence of catalytic amount of solid KOH in ethanol in excellent yields. The compounds were evaluated for anticancer activity against human breast cancer MCF-7 (estrogen responsive proliferative breast cancer model) and MDA-MB-231 (estrogen independent aggressive breast cancer model) cell lines, HeLa (cervical cancer) cell line, and human embryonic kidney (HEK-293) cells. Most of the compounds preferentially inhibited the growth of the aggressive human breast cancer cell lines, MDA-MB-231 in the range of 4.4-30 μM. The two compounds 9 and 29 proved to be better anticancer agents than the standard drug tamoxifen against the MDA-MB-231 cell lines. Mode of action of these compounds was established to be apoptosis, cell cycle arrest and loss of mitochondrial membrane potential.

A Facile and General Synthesis of Tropolonyl-Substituted Chalcone Derivatives

A facile and general synthesis of a series of new troplonyl-substituted chalcone derivatives by Claisen–Schmidt condensation reaction from 3-acetyltropolone and substituted benzaldehydes as well as pyridine aldehydes is described. The method using 5% aq. KOH as catalyst and 50% aq. methanol as solvent is attractive since it specifically generates (E)-isomers with high yields under mild reaction conditions.

Antispasmodic activity of licochalcone A, a species-specific ingredient of Glycyrrhiza inflata roots

Licochalcone A, a species-specific and characteristic retrochalcone ingredient of Glycyrrhiza inflata root, has been shown to possess multiple bioactive properties. However, its muscle relaxant activity has not been reported previously. Licochalcone A showed a concentration-dependent relaxant effect on the contraction induced by carbachol (50% effective concentration (EC50) = 5.64 ± 1.61 μm). KCl (EC50 5.12 ± 1.68 μm), BaCl2 (EC50 1.97 ± 0.48 μm) and A23187 (EC50 2.63 ± 2.05 μm). Pretreatment with licochalcone A enhanced the relaxant effect of forskolin, an adenylyl cyclase activator, on the contraction in a similar manner to 3-isobutyl-1-methylxanthine (IBMX), a phosphodiesterase (PDE) inhibitor. Furthermore, the IC50 (22.1 ± 10.9 μm) of licochalcone A against cAMP PDE was similar to that of IBMX (26.2 ± 7.4 μm). These results indicated that licochalcone A may have been responsible for the relaxant activity of G. inflata root and acted through the inhibition of cAMP PDE.

Solvent free synthesis of 1,3-diaryl-2-propenones catalyzed by commercial acid-clays under ultrasound irradiation

This paper presents a novel solvent free method of synthesis of trans-chalcones. The method was based on ultrasound irradiation of the reagents (aryl methyl ketones and aryl aldehydes) in presence of commercial acid-montmorillonites as catalysts. The trans-chalcones were synthesized in high yields (85-95%) and excellent selectivity in a short reaction time.

A concise synthesis of licochalcone E and its regio-isomer, licochalcone F

Licochalone E is one of the retrochalcones isolated from Glycyrrhiza inflata which shows potent cytotoxicty against human tumor cell lines. Biological studies suggested that topoisomerase I inhibition correlates with cytotoxic properties. Other research revealed that licochalcone E modulats the nuclear factor (NF)-kB and Bcl-2 families to induce endothelial cell apoptosis. Since licochalcone E has been isolated recently, synthetic information on this compound has not been reported yet. Therefore we report the concise synthesis of licochalcone E and its regio-isomer, tentatively called licochalcone F, by employing Claisen rearrangement for key intermediate synthesis.