Synthesis and antifungal activities of 5-(3,4,5-trimethoxyphenyl)-2-sulfonyl-1,3,4-thiadiazole and 5-(3,4,5-trimethoxyphenyl)-2-sulfonyl-1,3,4-oxadiazole derivatives

Starting from the key intermediate 5-(3,4,5-trimethoxyphenyl)-1,3,4-thiadiazole-2-thiol (4) or the oxadiazole analogue (5), the title compounds 9 and 10 are synthesized by a two-step process. Thioetherification reaction of 4 or 5 with an organic halide catalyzed by indium or indium tribromide first affords appropriate sulfide 7 or 8, which is then converted into title compounds 9 or 10 by hydrogen peroxide oxidation catalyzed by ammonium molybdate in ionic liquid [bmim]PF6. The structures are unequivocally confirmed by spectroscopic (IR, 1H and 13C NMR) data and elemental analyses. The structures of 8d and 10q are further established by X-ray crystallographic diffraction analysis. The compounds have been shown to be fungicidally active. Title compounds 10i and 10j can inhibit mycelia growth by approximately 50% (EC50) at 2.9-93.3 microg/mL in vitro against 10 kinds of fungi.     

Synthesis and cytotoxicity of 3,4-disubstituted-5-(3,4,5-trimethoxyphenyl)-4H-1,2,4-triazoles and novel 5,6-dihydro-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole derivatives bearing 3,4,5-trimethoxyphenyl moiety

A series of 3,4-disubstituted-5-(3,4,5-trimethoxyphenyl)-4H-1,2,4-triazoles and some novel 5,6-dihydro-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles bearing 3,4,5-trimethoxyphenyl moiety were synthesized and screened for their anticancer activity. The preliminary bioassay results indicated that compounds 14 and 16 showed much stronger cytotoxicity than Doxorubicin against HepG2 cell lines with IC(50) values of 0.58 and 3.17 μM, respectively. Meanwhile compound 16 also exhibited a broad spectrum of antitumor activity against MCF-7 and MKN45 with IC(50) values of 10.92 and 13.79 μM, respectively.     

Design,synthesis, cytotoxic evaluation and tubulin inhibitory activity of 4-aryl-5-(3,4,5-trimethoxyphenyl)-2-alkylthio-1H-imidazole derivatives

A new series of 4-aryl-5-(3,4,5-trimethoxyphenyl)-2-alkylthio-1H-imidazoles were synthesized and their cytotoxic activities in vitro against four different cell lines (HT-29, MCF-7, NIH-3T3, AGS) were evaluated. Compound 6g bearing 3,4,5-trimethoxyphenyl moiety on ring A and 4-methoxy substituent on ring B displayed potent cytotoxic activity against all cell lines. Flow cytometry analysis and microtubule polymerization assay confirmed that cytotoxic activities of this compound were related to inhibitory effect against microtubules polymerization. Molecular modeling studies revealed that compound 6g could strongly bind to the colchicine binding site of α,β-tubulin through hydrogen bond interactions with Thrα179 and Cysβ241.     

Lignans from Mosla scabra

Two new cyclobutane-type lignans, named moslolignans A and B, together with two known ones, andamanicin and magnosalin, were isolated from the whole plant of Mosla scabra. Their structures were established as 1beta*,2beta*,3alpha*,4alpha*-1,2-dimethyl-3-(3- methoxy-4,5-methylene-dioxyphenyl)-4-(2,4,5-trimethoxyphenyl)-cycl obutane and 1beta*,2beta*,3alpha*,4alpha*-1,2-dimethyl-3-(2, 5-dimethoxy-3,4-methylenedioxyphenyl)-4-(2,4,5-trimethoxyphenyl)-cyclobu tane by spectroscopic methods. This is the first report of naturally-occurring cyclobutane-type lignans with asymmetrical substitutions.     

Synthesis,cytotoxic evaluation and molecular docking study of 2-alkylthio-4-(2,3,4-trimethoxyphenyl)-5-aryl-thiazoles as tubulin polymerization inhibitors

A series of cis-restricted 2-alkylthio-4-(2,3,4-trimethoxyphenyl)-5-aryl-thiazole analogues of combretastatin A-4 were synthesized and investigated for inhibition of cell proliferation against three cancer cell lines, HT-29, MCF-7, and AGS, and a normal mouse fibroblastic cell line, NIH-3T3, using an MTT assay. The biological study showed that 2-(methylthio) substituted compounds showed little cytotoxic activity against the four cell lines. In contrast, the presence of the 2-(benzylthio) group on the thiazole ring resulted in a significant improvement in cytotoxic activity relative to the 2-(methylthio) substituted derivatives. Furthermore, the inhibition of tubulin polymerization by some potent compounds was evaluated. All the compounds studied were moderate tubulin polymerization inhibitors. The flow cytometry analysis confirmed that the synthesized compounds led to cell cycle arrest at the G₂/M phase. Docking simulation was performed to insert these compounds into the crystal structure of tubulin at the colchicine binding site to determine a probable binding model.     

Two neolignans from Perilla frutescens and their inhibition of nitric oxide synthase and tumor necrosis factor-alpha expression in murine macrophage cell line RAW 264.7

Two neolignans were isolated from leaves of Perilla frutescens (Labiatae) as inhibitors of nitric oxide syntheses (IC50 5.9 microM and 53.5 microM, respectively) and tumor necrosis factor-alpha in lipopolysaccharide-activated RAW 264.7 cells. Their structures were identified as 1beta,2alpha,3beta,4alpha-1,2-dimethyl-3,4-bis-(2,4,5-trimethoxyphenyl)-cyclobutane (magnosalin), and 1alpha,2beta,3beta,4alpha-1,2-dimethyl-3,4-bis-(2,4,5-trimethoxyphenyl)-cyclobutane (andamanicin), and their activities were confirmed as resulted from the suppressed expression of inducible nitric oxide synthase enzyme and from the secretion of tumor necrosis factor-alpha from activated macrophages.     

Synthesis, structure, and bioactivity of N'-substituted benzylidene-3,4,5-trimethoxybenzohydrazide and 3-acetyl-2-substituted phenyl-5-(3,4,5-trimethoxyphenyl)-2,3-dihydro-1,3,4-oxadiazole derivatives

Some 3-acetyl-2-substituted phenyl-5-(3,4,5-trimethoxyphenyl)-2,3-dihydro-1,3,4-oxadiazole derivatives were synthesized by cyclization reaction of N'-substituted benzylidene-3,4,5-trimethoxybenzohydrazide in acetic anhydride. Their structures were verified by elemental analysis, IR, (1)H NMR, and (13)C NMR. Compound 3i was provided with X-ray crystallographic data. The compounds were evaluated for their antiproliferative activities against some cancer cells in vitro by MTT method. Among them, 2a, 2b, 2c, 2f, 3l, and 3m were highly effective against PC3 cells and 2a, 2c, and 2f showed moderate activities against Bcap37 and BGC823 cells. The IC(50) values of high active compounds 2a, 2b, 2c, 2f, 3l, and 3m against PC3 cells were 0.2, 1.8, 0.2, 1.2, 1.7, and 0.3muM, respectively.     

Water soluble prodrugs of the antitumor agent 3-[(3-amino-4-methoxy)phenyl]-2-(3,4,5-trimethoxyphenyl)cyclopent-2-ene-1-one

Fourteen prodrugs of the antitumor agent 3-[(3-amino-4-methoxy)phenyl]-2-(3,4,5-trimethoxyphenyl)cyclopent-2-ene-1-one (1) were prepared to improve its water solubility and potency. These prodrugs include alpha-amino acid (1a-1h), aliphatic amino acid (1i-1l), phosphoramidate (1m), and phosphate (1n) derivatives. All of the prodrugs showed improved water solubility. A number of the amino acid prodrugs (1a, 1b, 1d-1f, 1h, 1j, and 1k) exhibited more potent antitumor activity compared to the parent compound (1). The phosphate prodrug 1n also offered a potent antitumor activity, but the phosphoramidate 1m did not show any antitumor activity in vivo. None of the prodrugs exhibited significant toxicities in mice. These results indicate that the design and preparation of the amino acid prodrugs (1a, 1b, 1d-1f, 1h, 1j, and 1k) and phosphate prodrug (1n) are beneficial for enhancing the antitumor activity of 1. The similar approaches may be used to improve water solubility and bioactivity of other poorly soluble aromatic amines.     

Synthesis and cytotoxicity of 3,4-diaryl-2(5H)-furanones

A series of 3,4-diaryl-2(5H)-furanone derivatives were synthesized and evaluated for their cytotoxicity in a small panel of cancer cell lines. Four out of 10 compounds in this series, for example 3-(3,4,5-trimethoxyphenyl)-4-(4-methoxyphenyl)-, 3-(3,4,5-trimethoxyphenyl)-4-(3-hydroxy-4-methoxyphenyl)-, 3-(3,4,5-trimethoxyphenyl)-4-(3-amino-4-methoxyphenyl)-, and 3-(3,4,5-trimethoxyphenyl)-4-(2-naphthyl)-2(5H)-furanones, were found to have potent cytotoxic activities with ED50 values of less than 20 nM in most of the cell lines tested.     

Inhibition of P-glycoprotein-mediated Multidrug Resistance (MDR) by N,N-bis(cyclohexanol)amine aryl esters: further restriction of molecular flexibility maintains high potency and efficacy

Conformational modulation of the aryl portion of a set of N,N-bis(cyclohexanol)amine aryl esters (1a-d) that are potent Pgp-dependent MDR inhibitors has been performed. Toward this end the trans-3-(3,4,5-trimethoxyphenyl)acrylic acid present in set 1 was substituted with 3-(3,4,5-trimethoxyphenyl)propanoic and 3-(3,4,5-trimethoxyphenyl)propiolic moieties to give sets 2 and 3, respectively. While the introduction of 3-(3,4,5-trimethoxyphenyl)propanoic moiety resulted in a definite drop in potency and efficacy, esterification with 3-(3,4,5-trimethoxyphenyl)propiolic acid gave four isomers (3a-d) that maintain high potency and possess optimal efficacy. These results are discussed in terms of conformational flexibility of the different sets of compounds.     

Determination of 2,2-dimethyl-N-(2,4,6-trimethoxyphenyl)-dodecanamide, a lipid regulator, in rat plasma and mesenteric lymph by reversed-phase high-performance liquid chromatography

2,2-Dimethyl-N-(2,4,6-trimethoxyphenyl)dodecanamide (I, CI-976) has been determined in rat mesenteric lymph and plasma using a rapid and sensitive high-performance liquid chromatographic method. The samples prepared from plasma and lymph by liquid—liquid extraction were analysed on a reversed-phase C₁₈ column using isocratic conditions and ultraviolet detection. The method was applied to the determination of levels of I in Wistar rats after intraduodenal administration of 110 mg/kg of I as a lipid emulsion.     

Synthesis of N2-(substituted benzyl)-3-(4-methylphenyl)indazoles as novel anti-angiogenic agents

To search for novel compounds with potent anti-angiogenic activity, a series of N(1)-(substituted benzyl)-3-(4-methylphenyl)-1H-indazoles (16, 18, 20, 22, 24, 26, 28, 30, 32) and N(2)-(substituted benzyl)-3-(4-methylphenyl)-2H-indazoles (17, 19, 21, 23, 25, 27, 29, 31, and 33) were synthesized. The structures of these regioisomers were established by IR, UV, and NMR spectral data. 3-(4-Methylphenyl)-1H-indazole (6) and the N(2)-substituted derivatives (17, 19, 21, 23, 25, 29, 31, 33) were evaluated for their anti-angiogenic activity. Most of them showed more prominent activity than ethyl 4-(1-benzyl-1H-indazol-3-yl)benzoate (YD-3). Among these tested compounds, 2-(4-chlorobenzyl)-3-(4-methylphenyl)-2H-indazole (19), 2-(4-methylbenzyl)-3-(4-methylphenyl)-2H-indazole (25), and 2-(4-methoxybenzyl)-3-(4-methylphenyl)-2H-indazole (31) showed significant anti-angiogenic activity and are worthy of further investigation.     

Extracellular matrix-derived peptide binds to alpha(v)beta(3) integrin and inhibits angiogenesis

Angiogenesis is associated with several pathological disorders as well as with normal physiological maintenance. Components of vascular basement membrane are speculated to regulate angiogenesis in both positive and negative manner. Recently, we reported that tumstatin (the NC1 domain of alpha 3 chain of type IV collagen) and its deletion mutant tum-5 possess anti-angiogenic activity. In the present study, we confirm that the anti-angiogenic activity of tumstatin and tum-5 is independent of disulfide bond requirement. This property of tum-5 allowed us to use overlapping synthetic peptide strategy to identify peptide sequence(s) which possess anti-angiogenic activity. Among these peptides, only the T3 peptide (69-88 amino acids) and T7 peptide (74-98 amino acids) inhibited proliferation and induced apoptosis specifically in endothelial cells. The peptides, similar to tumstatin and the tum-5 domain, bind and function via alpha(v)beta(3) in an RGD-independent manner. Restoration of a disulfide bond between two cysteines within the peptide did not alter the anti-angiogenic activity. Additionally, these studies show that tumstatin peptides can inhibit proliferation of endothelial cells in the presence of vitronectin, fibronectin, and collagen I. Anti-angiogenic effect of the peptides was further confirmed in vivo using a Matrigel plug assay in C57BL/6 mice. Collectively, these experiments suggest that the anti-angiogenic activity of tumstatin is localized to a 25-amino acid region of tumstatin and it is independent of disulfide bond linkage. Structural features and potency of the tumstatin peptide make it highly feasible as a potential anti-cancer drug.     

Synthesis,antitumor activity and molecular docking study of some novel 3-benzyl-4(3H)quinazolinone analogues

A novel series of 3-benzyl-substituted-4(3H)-quinazolinones were designed, synthesized and evaluated for their in vitro antitumor activity. The results of this study demonstrated that 2-(3-benzyl-6-methyl-4-oxo-3,4-dihydroquinazolin-2-ylthio)-N-(3,4,5-trimethoxyphenyl)acetamide, 2-(3-benzyl-6,7-dimethoxy-4-oxo-3,4-dihydroquinazolin-2-ylthio)-N-(3,4,5-trimethoxyphenyl)acetamide and 3-(3-benzyl-6-methyl-4-oxo-3,4-dihydroquinazolin-2-ylthio)-N-(3,4,5-trimethoxyphenyl)-propanamide have shown amazing broad spectrum antitumor activity with mean GI₅₀ (10.47, 7.24 and 14.12?µM. respectively), and are nearly 1.5–3.0-fold more potent compared with the positive control 5-FU with mean GI₅₀, 22.60?µM. On the other hand, compounds 6 and 10 yielded selective activities toward CNS, renal and breast cancer cell lines, whereas compound 9 showed selective activities towards leukemia cell lines. Molecular docking methodology was performed for compounds 7 and 8 into ATP binding site of EGFR-TK which showed similar binding mode to erlotinib, while compound 11 into ATP binding site of B-RAF kinase inhibited the growth of melanoma cell lines through inhibition of B-RAF kinase, similar to PLX4032.     

The inhibition of tube formation in a collagen-fibrinogen, three-dimensional gel by cleaved kininogen (HKa) and HK domain 5 (D5) is dependent on Src family kinases

Cleaved high molecular weight kininogen (HKa), as well as its domain 5 (D5), inhibits migration and proliferation induced by angiogenic factors and induces apoptosis in vitro. To study its effect on tube formation we utilized a collagen-fibrinogen, three-dimensional gel, an in vitro model of angiogenesis. HKa, GST-D5 and D5 had a similar inhibitory effect of tube length by 90+/-4.5%, 86+/-5.5% and 77+/-12.9%, respectively. D5-derived synthetic peptides: G440-H455 H475-H485 and G486-K502 inhibited tube length by 51+/-3.7%, 54+/-3.8% and 77+/-1.7%, respectively. By a comparison of its inhibitory potency and its sequences, a functional sequence of HKa was defined to G486-G496. PP2, a Src family kinase inhibitor, prevented tube formation in a dose-dependent manner (100-400 nM), but PP3 at 5 microM, an inactive analogue of PP2, did not. HKa and D5 inhibited Src 416 phosphorylation by 62+/-12.3% and 83+/-6.1%, respectively. The C-terminal Src kinase (Csk) inhibits Src kinase activity. Using a siRNA to Csk, expression of Csk was down-regulated by 86+/-7.0%, which significantly increased tube length by 27+/-5.8%. The addition of HKa and D5 completely blocked this effect. We further showed that HKa inhibited Src family kinase activity by disrupting the complex of uPAR, alphavbeta3 integrin and Src. Our results indicate that the anti-angiogenic effect of HKa and D5 is mediated at least in part through Src family kinases and identify a potential novel target for therapeutic inhibition of neovascularization in cancer and inflammatory arthritis.     

Anti-angiogenic activity of basic-type, selective cyclooxygenase (COX)-1 inhibitors

Indole- and indoline-type basic COX-1-selective competitive inhibitors, 5-amino-1-(3,5-dimethylbenzoyl)-1H-indole (1) and 5-amino-1-(3,5-dimethylphenyl)-2,3-dihydro-1H-indole (2), were found to possess anti-angiogenic activity estimated as a tube formation-inhibition using human umbilical vein endothelial cells (HUVECs).     

trans-2,5-Bis-(3,4,5-trimethoxyphenyl)tetrahydrofuran. An orally active specific and competitive receptor antagonist of platelet activating factor

trans-2,5-Bis(3,4,5-trimethoxyphenyl)tetrahydrofuran (L-652,731) is found to be a potent and orally active platelet activating factor (PAF)-specific and competitive receptor antagonist. It potently inhibits [3H]PAF (1 nM) binding to receptor sites on rabbit platelet membranes with an ED50 of 2 X 10(-8) M under the assay condition without the addition of mono- or divalent cations. In a comparative study, it is more potent than CV-3988, kadsurenone, and ginkgolide B as a receptor antagonist. The equilibrium dissociation constants (KB) of L-652,731 obtained either from the inhibition of receptor binding or from the inhibition of PAF-induced aggregation of gel-filtered rabbit platelet are 2.7 X 10(-8) and 2.1 X 10(-8) M, respectively. The agreement of these KB determinations based on receptor and cellular function suggests that L-652,731 does not inhibit other steps following PAF-receptor binding. L-652,731 does not antagonize the binding of several radioligands to their respective receptor. It shows no inhibitory effect on platelet aggregation induced by other aggregating agents including thrombin, collagen, A-23187, arachidonic acid, epinephrine, and ADP. L-652,731 is orally active; it inhibits PAF-induced rat cutaneous vascular permeability with an ED50 of 30 mg/kg orally. Significant inhibitory results of L-652,731 suggest that PAF may be partially involved in cutaneous vascular permeability induced by histamine and bradykinin.     

(2E)-1-(2,4,6-Trimethoxyphenyl)-3-(4-chlorophenyl)prop-2-en-1-one,a Chalcone Derivative,Promotes Apoptosis by Suppressing RAS-ERK and AKT/FOXO3a Pathways in Hepatocellular Carcinoma Cells

Background : Liver cancer is an extremely common cancer with the highest mortality rate and poor prognosis. Owing to their low systemic toxicity and few side effects, natural compounds may provide better therapeutic effects for patients. (2E)-1-(2,4,6-trimethoxyphenyl)-3-(4-chlorophenyl)prop-2-en-1-one (TMOCC), a chalcone derivative, exhibits cytotoxicity towards many tumor cells. However, the anticancer mechanism of TMOCC has not been elucidated in human hepatocellular carcinoma (HCC). Methods : Cell Counting Kit-8 and colony formation assays were used to evaluate the effects of TMOCC on viability and proliferation. Mitochondrial transmembrane potential and flow cytometry assays were used to detect apoptosis. The expression levels of proteins related to apoptosis, the RAS-ERK and AKT/FOXO3a signaling pathways were assessed using western blot. Potential targets of TMOCC were detected using molecular docking analysis. Results : TMOCC inhibited viability and proliferation, and induced the loss of mitochondrial transmembrane potential, apoptosis and DNA double-strand breaks in both HCC cells. The RAS-ERK and AKT/FOXO3a signaling pathways were suppressed by TMOCC. Finally, ERK1, PARP-1, and BAX were identified as potential targets of TMOCC. Conclusion : Taken together, our results show that TMOCC promotes apoptosis by suppressing the RAS-ERK and AKT/FOXO3a signaling pathways. TMOCC may be a potential multi-target compound that is effective against liver cancer.     

Chemistry of tris(2,4,6-trimethoxyphenyl)phosphine with rhodium(I) and iridium(I) olefin complexes

Rh(I) and Ir(I) complexes of the type [Rh(cod)(η²-TMPP)]¹⁺ (1) and M(cod)(η²-TMPP-O) (M = Rh (2), Ir (3); cod = cyclooctadiene; TMPP = tris(2,4,6-trimethoxyphenyl)phosphine; TMPP-O = mono-demethylated form of TMPP) have been isolated from reactions of [M(cod)Cl]₂ with M′BF₄ (M′ = Ag⁺, K⁺, Na⁺) followed by addition of the tertiary phosphine ligand. This chemistry is dependent on the identity of the metal, as both the cationic phosphine complex and the neutral phosphino-phenoxide compound are stable for Rh(I), whereas only the latter is stable for Ir(I). The three complexes have been characterized by IR and NMR (¹H and ³¹P) spectroscopies as well as by cyclic voltammetry. The ¹H NMR spectrum of [Rh(cod)(η²-TMPP)]¹⁺ (1) is in accord with the formula and reveals that the TMPP phenyl rings are undergoing rapid exchange between coordinated and non-coordinated modes; the corresponding spectra of 2 and 3 support free rotation about the P---C bonds of the unbound phenyl rings with no fluxionality of the bound demethylated ring. The ³¹P{¹H} NMR spectrum of the neutral species 2 exhibits a significant upfield shift with respect to the analogous cationic compound 1. This shielding is the result of improved electron donation to the metal from a phenoxide group as compared to an ether substituent. In situ addition of CO to the reaction between TMPP and [Rh(cod)Cl]₂ or [Ir(cod)Cl]₂ in the presence of M′BF₄ results in the isolation of the monocarbonyl species [Rh(TMPP)(η²-TMPP)(CO)][BF₄] (5) and the stable dicarbonyl compound [Ir(TMPP)₂(CO)₂][BF₄] (4), respectively. Single crystal X-ray data for

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. The geometry of 4 is square planar, with essentially ideal angles for the mutually trans disposed phosphine and carbonyl ligands, as found in earlier studies for the analogous Rh dicarbonyl compound. The ¹H NMR spectrum of 4 supports the assignment of magnetically equivalent phosphorus nuclei in solution. The results of this study indicate that cyclooctadiene is a particularly strong ligand for monovalent late transition metals ligated by TMPP, to the extent that it is inert with respect to substitution in the absence of π-acceptor ligands such as carbon monoxide.