Biological evaluation of sulfone derivatives as anti-inflammatory and tumor cells growth inhibitory agents

Turning sulfonyl and sulfonimidoyl fluoride electrophiles into sulfur(VI) radicals for alkene ligation

Sulfonyl and sulfonimidoyl fluorides are versatile substrates in organic synthesis and medicinal chemistry. However, they have been exclusively used as S(VI)+ electrophiles for defluorinative ligations. Converting sulfonyl and sulfonimidoyl fluorides to S(VI) radicals is challenging and underexplored due to the strong bond dissociation energy of SVI-F and high reduction potentials, but once achieved would enable dramatically expanded synthetic utility and downstream applications. In this report, we disclose a general platform to address this issue through cooperative organosuperbase activation and photoredox catalysis. Vinyl sulfones and sulfoximines are obtained with excellent E selectivity under mild conditions by coupling reactions with alkenes. The synthetic utility of this method in the preparation of functional polymers and dyes is also demonstrated.

Sulfolane: Magic Extractor or Bad Actor? Pilot-Scale Study on Solvent Corrosion Potential

The sulfur-containing derivatives and their metabolites, regarded as ‘old devils of green’ chemistry, constitute a relevant class of air/water/soil contaminants in over-polluted world. In fact, some industrially-engineered solvents have become environmentally unfavorable. An attractive alternative to commonly used industrial liquids is sulfolane (C4H8SO2), an anthropogenic medium. The main objective of this paper is the comprehensive review focusing mainly on the state-of-the-art aspects of the sulfolane synthesis, application of sulfolane as an extractive solvent due to its ‘unique’ physicochemical properties as well as the potential of sulfolane to cause equipment corrosion and subsequent spills. The potential risk for groundwater contamination, danger for human health and ways of sulfolane biodegradation were briefly reviewed as well. Interestingly, the analysis performed on data stored in the Reaxys database revealed an alternating tendency of waxing and waning interest in sulfolane during the space of the last fifty years. Moreover, the primary goal of the presented case study was to verify applicability of industrial, multi-electrochemical technique for reliable detection of corrosion in low conductive process fluids. Several aspects of corrosion measurement including the impact of process parameters (temperature) and impurities (oxygen and chlorides) on stainless steel corrosion in pure sulfolane were investigated briefly.

Label-free quantitative proteomic analysis of inhibition of Xanthomonas axonopodis pv. citri by the novel bactericide Fubianezuofeng

To understand the antibacterial mechanism of the new bactericide 2-(methylsulfonyl)-5- (4-fluorobenzyl)-1, 3, 4-oxadiazole (Generic name: Fubianezuofeng), we performed label-free quantitative proteomics analysis of the response of Xanthomonas axonopodis pv. citri (Xac) strain 29-1 to Fubianezuofeng. A total of 1133 proteins were identified in the treatment and control groups. Upon treatment with the 1/2 minimum inhibitory concentration (MIC), 339 proteins were found to be differentially expressed (fold changes>1.5, p<0.05) with 99 upregulated and 240 down-regulated. In comparison, 314 proteins were differentially expressed (125 up-regulated, 189 down-regulated) at MIC. The differentially expressed proteins were enriched for those involved in the pyrimidine metabolic pathway. The results offer a complete view of the proteome changes in bacteria in response to Fubianezuofeng.

Sulfone-Containing Methacrylate Homopolymers: Wetting and Thermal Properties

Although the sulfonyl functional group has a large dipole moment and compounds containing them (sulfones) have correspondingly high dielectric constants, this chemical structure has been neglected for use as a functional group to render surfaces hydrophilic. We have prepared three methacrylate polymers containing side chains capped with sulfolane, methylsulfone, and ethylsulfone functionality. The sulfolane-containing polymer exhibits an unusually high glass transition temperature (Tg = 188°C) for a methacrylate polymer and slightly different thermal degradation behavior than the other two sulfone-containing polymers, likely due to the bulky structure of the sulfolane group in the polymer side chain. At macroscopic polymer film/water interfaces, the sulfone-containing side chains exposed to the interface impart hydrophilic properties as assessed by contact angle analysis. The hydrophilicities of sulfolane and methylsulfone surfaces are similar, and greater than the ethylsulfone surface. Although the chemical compositions of the sulfolane and ethylsulfone polymers are almost identical, the five-membered ring structure of sulfolane allows the sulfonyl moiety to be exposed at the interface in a manner similar to that of the methylsulfone polymer. The sulfonyl group at the ethylsulfone polymer/water interface is slightly masked by the ethyl group. Interestingly, the sulfolane surface displays a higher affinity to methylene iodide and n-hexadecane probe fluids compared to the other sulfone surfaces, suggesting that the five-membered ring structure of the sulfolane moiety can orient in a manner that shelters the sulfonyl group at hydrophobic interfaces.

Synthesis of Unsymmetrical Sulfides and Their Oxidation to Sulfones to Discover Potent Antileishmanial Agents

Unsymmetrical sulfides were first synthesized using combinations of a 1,3-dicarbonyl, an aromatic aldehyde and a thiol in the presence of 10 mol % ethanolic piperidine. These sulfides derivatives were subsequently converted into corresponding sulfones via oxidation in the presence of m-chloroperoxybenzoic acid (m-CPBA) at ice-bath to room temperature. The former reaction was achieved at room temperature through one-pot three-component. The later was obtained in good yields using mild reaction conditions with flexibility in choice from a range of substrates. The antimicrobial properties of the newly synthesized sulfone derivatives were investigated against the protozoan parasite, Leishmania donovani, a causative agent of visceral leishmaniasis (VL). Nine sulfone derivatives were found to be efficacious and exhibited significant antimicrobial activity. Further, these compounds were nontoxic on murine peritoneal macrophages thus eliminating potential cytoxicity in the host cells. These compounds may be indicated as potential leads in the treatment of visceral leishmaniasis.

Cytotoxicity and sustained release of modified divinylsulfone from silk based 3D construct

Monovinylsulfones have been extensively studied for its biological activities but modified divinylsulfones (mDVS2) were largely neglected due to the non-availability of appropriate synthetic routes. The present report describes the potential of a unique derivative of divinylsulfone as a remedial molecule. The mDVS2, available in reasonably large amount through an easy synthesis route, incites necrosis in invasive and non-invasive breast cancer cells in a time and concentration dependent manner. This molecule is further used to fabricate mDVS2 embedded silk based 3D scaffolds in order to achieve sustained release. The entrapped molecules retain their activity over time, as 100% cell death is observed within 7 days. The findings demonstrate the cytotoxic property of mDVS and highlight the importance of under utilized mDVSs as potential therapeutic agents.

Design, synthesis, and antibacterial activity against rice bacterial leaf blight and leaf streak of 2,5-substituted-1,3,4-oxadiazole/thiadiazole sulfone derivative

A series of 2,5-substituted-1,3,4-oxadiazole/thiadiazole sulfone derivatives were synthesized and evaluated for their antibacterial activities against rice bacterial leaf blight and leaf streak caused by Xanthomonas oryzae pv. oryzae and Xanthomonas oryzae pv. oryzicolaby via the turbidimeter test in vitro. Antibacterial bioassay results indicated that most compounds demonstrated good inhibitory effect antibacterial bioactivities against rice bacterial leaf blight and leaf streak. Among the title compounds, compound 6c demonstrated the best inhibitory effect against rice bacterial leaf blight and leaf streak with half-maximal effective concentration (EC50) values of 1.07 and 7.14 μg/mL, respectively, which were even better than those of commercial agents such as Bismerthiazol and Thiediazole Copper. In vivo antibacterial activities tests at greenhouse conditions demonstrated that the controlling effect of compounds 6c (43.5%) and 6g (42.4%) against rice bacterial leaf blight were better than those of Bismerthiazol (25.5%) and Thiediazole Copper (37.5%).

Synthesis, antibacterial activities, and 3D-QSAR of sulfone derivatives containing 1, 3, 4-oxadiazole moiety

A series of sulfone derivatives containing 1, 3, 4-oxadiazole moiety were prepared and evaluated for their antibacterial activities by the turbidimeter test. Most compounds inhibited growth of Ralstonia solanacearum (R. solanacearum) from tomato and tobacco bacterial wilt with high potency, among which compounds 5a and 5b exhibited the most potent inhibition against R. solanacearum from tomato and tobacco bacterial wilts with EC50 values of 19.77 and 8.29 μg/mL, respectively. Our results also demonstrated that 5a, 5b, and a number of other compounds were more potent than commercial bactericides Kocide 3000 and Thiodiazole Copper, which inhibited R. solanacearum from tomato bacterial wilt with EC50 values of 93.59 and 99.80 μg/mL and tobacco bacterial wilt with EC50 values of 45.91 and 216.70 μg/mL, respectively. The structure-activity relationship (SAR) of compounds was studied using three-dimensional quantitative structure-activity relationship (3D-QSAR) models created by comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA) based on compound bioactivities against tomato and tobacco bacterial wilts. The 3D-QSAR models effectively predicted the correlation between inhibitory activity and steric-electrostatic properties of compounds.

Inhibition of tobacco bacterial wilt with sulfone derivatives containing an 1,3,4-oxadiazole moiety

A series of new sulfone compounds containing the 1,3,4-oxadiazole moiety were designed and synthesized. Their structures were identified by (1)H and (13)C nuclear magnetic resonance and elemental analyses. Antibacterial bioassays indicated that most compounds exhibited promising in vitro antibacterial bioactivities against tobacco bacterial wilt at 200 μg/mL. The relationship between structure and antibacterial activity was also discussed. Among the title compounds, 5'c, 5'h, 5'i, and 5'j could inhibit mycelia growth of Ralstonia solanacearum in vitro by approximately 50% (EC(50)) at 39.8, 60.3, 47.9, and 32.1 μg/mL, respectively. Among them, compound 5'j was identified as the most promising candidate due to its stronger effect than that of Kocide 3000 [Cu(OH)(2)] within the same concentration range. Field trials demonstrated that the control effect of compound 5'j against tobacco bacterial wilt was better than that of the commercial bactericide Saisentong. For the first time, the present work demonstrated that sulfone derivatives containing 1,3,4-oxadiazole can be used to develop potential bactericides for plants.

Synthesis, Anti-Arthritic, and Anti-Inflammatory Activity of N-Tosyl aza Cyclophanes

The synthesis of novel N-tosyl tetraaza cyclophanes and N-tosyl diaza cyclophane incorporating m-terphenyl as spacer units is described. Anti-arthritic activity was studied by inhibition of the protein denaturation method (bovine serum albumin). All the N-tosyl aza cyclophanes exhibit excellent anti-arthritic activity. Anti-inflammatory activity of the synthesized cyclophanes was investigated using the human red blood cells (HRBC) membrane stabilization method and some of the N-tosyl aza cyclophanes exhibited good anti-inflammatory activity.

Synthesis and antifungal activity of novel sulfone derivatives containing 1,3,4-oxadiazole moieties

A series of new sulfone compounds containing 1,3,4-oxadiazole moieties were synthesized. The structures of these compounds were confirmed by spectroscopic data (IR, ¹H- and ¹³C-NMR) and elemental analyses. Antifungal tests indicated that all the title compounds exhibited good antifungal activities against eight kinds of plant pathogenic fungi, and some showed superiority over the commercial fungicide hymexazol. Among them, compounds 5d, 5e, 5f, and 5i showed prominent activity against B. cinerea, with determined EC₅₀ values of 5.21 μg/mL, 8.25 µg/mL, 8.03 µg/mL, and 21.00 µg/mL, respectively. The present work demonstrates that sulfone derivatives such as 5d containing a 1,3,4-oxadiazole moiety can be used as possible lead compounds for the development of potential agrochemicals.

Inhibition of pro-inflammatory mediators and tumor cell proliferation by Anisomeles indica extracts

Anisomeles indica (L.) Kuntze (Labiatae), is a traditional anti-inflammatory herb used in Taiwan. The aqueous and methanolic extracts of whole plants, leaves, flowers and stems; and chloroform and n-butanol fractions of methanol extract, from A. indica were investigated for their anti-inflammatory activity on murine peritoneal macrophages. In addition, the tumor cells proliferation inhibition activities of these extracts were also evaluated against a panel of tumor cell lines such as Colon 205, PC 3, HepG2 and MCF 7. Treatment with A. indica extracts did not reduce cell viability at any dose used. However, all the extracts significantly inhibited the enhanced production of NO radicals, and pro-inflammatory cytokines (TNF-alpha, and IL-12) induced by LPS/IFN-gamma in a dose-dependent manner. Furthermore, methanolic extracts of leaves and flowers significantly and dose-dependently arrest mitogen-stimulated spleen cells in G0/G1 stage, in addition to their cell proliferation inhibition against Colon 205, MCF 7 and PC 3 by 94, 82; 98, 71; 82, 98%, respectively, at 200 microg/mL concentration. This is the first report on A. indica extracts for their growth inhibitory activities, against inflammatory mediator production, and human tumor cell lines, colon, prostate, hepatoma and breast cells proliferation.

Anti-oxidant and inflammatory mediator's growth inhibitory effects of compounds isolated from Phyllanthus urinaria

Phyllanthus urinaria Linnea (Euphorbiaceae), is a traditional anti-hepatitis herb used in Taiwan. In continuation of our search for potent natural anti-inflammatory agents, from the ethanolic extract of this plant, nine compounds including phyllanthin (1), phyltetralin (2), trimethyl-3,4-dehydrochebulate (3), methylgallate (4), and rhamnocitrin (5), methyl brevifolincarboxylate (6), beta-sitosterol-3-O-beta-d-glucopyranoside (7), quercitrin (8), and rutin (9) were isolated. The structures of compounds 3 and 6 were established based on NMR and mass spectral studies. The isolates 1-9 were investigated for their antioxidant, and anti-inflammatory activities in vitro. In the antioxidant assay, the isolates 3, 4 and 6 exhibited significant DPPH radical scavenging activity with an IC(50) value of 9.4, 9.8 and 8.9 microM, respectively. On the other hand, in the inflammatory mediators growth inhibitory assay from LPS/interferon (IFN)-gamma-activated peritoneal macrophages, all the isolates except 7, significantly and dose-dependently inhibited the enhanced production of NO radicals, and such modulation was closely associated with the inhibition of tumor necrosis factor (TNF)-alpha and interleukin (IL)-6. In addition, 30 microM of isolates 3 and 6, and 50 microM of 4, significantly arrest the mitogen-stimulated spleen cells in G0/G1 stage. This is the first report on Phyllanthus urinaria isolates for their growth inhibitory activities against inflammatory mediators, in addition to spleen cell cycle arrest in G0/G1 stage. Therefore, these isolates from Phyllanthus urinaria may be useful for the treatment of cell-mediated immune diseases.

Evaluation of the anti-inflammatory and anti-proliferation tumoral cells activities of Antrodia camphorata, Cordyceps sinensis, and Cinnamomum osmophloeum bark extracts

The extracts of chloroform (1) and methanol (2) from Antrodia camphorata (AC), and chloroform (3) and n-butanol (4) fractions of methanol extract from Cordyceps sinensis (CS), and hexane (5), ethyl acetate (6), and methanol (7) from Cinnamomum osmophloeum bark (CO) were evaluated for their anti-inflammatory as well as tumor-cell growth inhibitory activities in vitro. All the tested extracts dose dependently inhibited the enhanced production of inflammatory mediators such as nitric oxide (NO) through reducing inducible NO synthase expression, and cytokines (tumor necrosis factor (TNF)-alpha and interleukin (IL)-12 in LPS/IFN-gamma activated murine peritoneal macrophages. In addition, extracts 1 from AC, and 5 and 6 from CO significantly arrest the mitogen-stimulated spleen cells in G0/G1 stage. On the other hand, all these extracts were also evaluated for their tumor-cell proliferation activities in different type of cancer cell lines such as Jurkat, HepG2, PC 3, Colon 205, and MCF 7 as well as normal PBMCs. Compared to untreated controls, the extracts 1, 2, and 4-7 were most active and inhibited Jurkat cells with IC50 value of 22, 40, 18, 4, 5, and 45 microg/ml, respectively. In addition, the extracts 5, 6, and 7 from CO showed potent growth inhibition of HepG2 and PC 3 with IC50 values of 35, 80, 55 microg/ml; and 42, 125, and 50 microg/ml, respectively. Similarly, the extracts 1 and 5 inhibited the growth of Colon 205 and MCF 7 cells with IC50 values of 65, 33; and 95 and 30 microg/ml, respectively. Interestingly, none of the tested extract has shown cytotoxicity towards normal PBMCs up to the concentration range studies (0-150 microg/ml). Taken together, these data suggest that the anti-inflammatory and anti-cancer properties of AC, CS, and CO might result from the growth inhibition of NO, TNF-alpha and IL-12, and tumor cells proliferation, respectively.