Sulfone Derivatives Research Articles

Cu-Catalyzed Synthesis of Alkylaminotroponyl Sulfones as Pseudomonas Aeruginosa Quorum Sensing Inhibitors Targeting lasI/R QS Circuitry.

The scarcity of novel bioactive molecules against multidrug-resistant (MDR) bacterial strains like Pseudomonas aeruginosa is alarming. This bacterial virulence is regulated via Quorum sensing (QS), a cell-cell communication process. Disabling QS circuits (las, pqs, rhl) with small molecules has been proposed as a potential strategy to prevent bacterial pathogenicity. This strategy focuses on interruption of bacterial virulence, rather than killing them to tackle the drug resistance problem. Herein, we describe the synthesis of rationally designed Alklyamionotroponyl Sulfone (ATS) derivatives by Cu-catalyzed C(sp2 )-H functionalization at tropone ring and the screening of their anti-QS activity against P. aeruginosa. Importantly, two sulfones (∼20 μM) remarkably exhibit the down regulation of the lasI/R QS genes. These molecules also inhibit swarming motility, biofilm formation and pyocyanin production, which reduce P. aeruginosa virulence in cells. Hence, ATS derivatives could be considered as potential therapeutic candidates for the treatment of P. aeruginosa infections.

Recent Advances in Organic Room-Temperature Phosphorescence of Heteroatom (B/S/P)-Containing Chromophores

Recent Advances in Organic Room-Temperature Phosphorescence of Heteroatom (B/S/P)-Containing Chromophores

Photocatalytic Desulfonylative Homocoupling of Benzylic Sulfone Derivatives

AbstractA desulfonylative homocoupling of benzylic sulfone derivatives through a photoredox Ir catalyst is described. The 3,5-bis(trifluoromethyl)phenyl group is an effective substituent on sulfonyl group in this reaction, providing the structurally diverse multiply arylated ethanes in good yields. The α-deuterated or α-fluorinated sulfones, which can be readily prepared by α-functionalization, were also applicable, highlighting an avenue to synthesize medicinally important structures.

Non-Covalent Interactions in the Crystal Structures of Perbrominated Sulfonium Derivatives of the closo-Decaborate Anion.

A new series of compounds based on perbrominated disubstituted sulfonium derivatives of the closo-decaborate anion (n-Bu4N)[2-B10Br9SR2] (R = n-Pr, i-Pr, n-Bu, n-C8H17, n-C12H25, n-C18H37) was obtained, characterised by modern physicochemical methods of analysis. According to the results of an X-ray diffraction study, some of the anions and solvate molecules were disordered. The cations (n-Bu4N)+ and anions [2-B10Br9SR2]− were associated via C-H…Br and H…H contacts. In addition, Br…Br interactions between anions were revealed. The role of these contacts was analysed in terms of Hirshfeld surface analysis, QTAIM theory and the NCI method using quantum chemical calculations. An increase in the size of the alkyl R moiety led to significant strengthening of the total energy of H…H interactions. In the case of R = -n-C18H37, a parallel mutual orientation of alkyl moieties was established that was similar to the packing of salts of fatty acids. The nature of C-H…Br and Br…Br interionic interactions was found to be attractive, in contrast to the repulsive nature of intermolecular Br…Br interactions.

Fluorescent Talarolactones from Talaromyces sp.

(+)-Talarolactone C (1), Talarolactone A (2), Talarolactone B (3, sulfoxide derivative), and Talarolactone D (4, sulfone derivative) were isolated from Talaromyces sp. which was cultured in rice medium with sodium butyrate. The structures of talarolactone analogs above were characterized by a combination of spectroscopic, X-ray crystallographic, and computational methods. These talarolactones and Talarolactone A sodium (5) with the same carbon skeleton showed different fluorescence characteristics.

Combinatorial Synthesis of Sulfonate Derivatives of α/β-Naphthol as Anti- Oomycete Agents.

Developing new, efficient, and environment-friendly small molecule fungicides is the key to effectively prevent and control plant pathogenic oomycetes. α/β-Naphthol is an important raw material for drug synthesis. Due to its special structure, α/β-naphthol and its analogs possess significant biological activity. The preparation and anti-oomycete activity of novel sulfonate derivatives based on α/β-naphthol against Phytophthora capsici have not been reported yet. Thirty-two sulfonate derivatives of α/β-naphthol (4a-p and 5a-p) were prepared. The structure of all title compounds was identified by 1H NMR, MS, and m.p. The anti-oomycete activity of 4a-p and 5a-p against P. capsici was determined using the mycelial growth rate method. With our ongoing research aimed at the discovery and development of fungicidal agents, 4a-p and 5a-p were designed and synthesized, and their anti-oomycete activity against P. capsici was evaluated in vitro. Two compounds 4a and 5a were found to have good anti-oomycete activity against P. capsici, and their corresponding EC50 values were 63.41 and 65.21 mg/L, respectively. It has been observed that the substituent R in these derivatives is aliphatic, which is very important for maintaining their anti-oomycete activity. The results lay a foundation for further design and development of sulfonate derivatives of α/β-naphthol as fungicidal agents. The structure- fungicidal activity relationship of α/β-naphthol derivatives is under investigation in our laboratory.

Mixture of Anthraquinone Sulfo-Derivatives as an Inexpensive Organic Flow Battery Negolyte: Optimization of Battery Cell.

Anthraquinone-2,7-disulfonic acid (2,7-AQDS) is a promising organic compound, which is considered as a negolyte for redox flow batteries as well as for other applications. In this work we carried out a well-known reaction of anthraquinone sulfonation to synthesize 2,7-AQDS in mixture with other sulfo-derivatives, namely 2,6-AQDS and 2-AQS. Redox behavior of this mixture was evaluated with cyclic voltammetry and was almost identical to 2,7-AQDS. Mixture was then assessed as a potential negolyte of anthraquinone-bromine redox flow battery. After adjusting membrane-electrode assembly composition (membrane material and flow field)), the cell demonstrated peak power density of 335 mW cm−2 (at SOC 90%) and capacity utilization, capacity retention and energy efficiency of 87.9, 99.6 and 64.2%, respectively. These values are almost identical or even higher than similar values for flow battery with 2,7-AQDS as a negolyte, while the price of mixture is significantly lower. Therefore, this work unveils the promising possibility of using a mixture of crude sulfonated anthraquinone derivatives mixture as an inexpensive negolyte of RFB.

Tetraphenylethylene sulfonate derivative as turn-on fluorescent sensor for berberine chloride detection in aqueous solution

A negatively-charged tetraphenylethylene derivative (TPE-SE) was designed and synthesized as turn-on fluorescent sensor for berberine chloride (BBC) detection in aqueous solution. The fluorescent property and detection mechanism were elucidated by UV–vis absorption spectra, photoluminescence spectra, dynamic light scattering experiments. The results reveal that the BBC can lead to aggregation-induced emission of TPE-SE due to the electrostatic interactions, endowing TPE-SE with excellent turn-on detecting ability, high selectivity and sensitivity to BBC. The detection limit is as low as 6.58 × 10−6M. These results should be applicable to fabricate special turn-on fluorescent sensors towards various antibiotics, and it is crucially important for achieving reasonable control and intake of small biomolecules.

Total Synthesis and Functional Evaluation of IORs, Sulfonolipid-based Inhibitors of Cell Differentiation in Salpingoeca rosetta.

The choanoflagellate Salpingoeca rosetta is an important model system to study the evolution of multicellularity. In this study we developed a new, modular, and scalable synthesis of sulfonolipid IOR-1A (six steps, 27 % overall yield), which acts as bacterial inhibitor of rosette formation in S. rosetta. The synthesis features a decarboxylative cross-coupling reaction of a sulfonic acid-containing tartaric acid derivative with alkyl zinc reagents. Synthesis of 15 modified IOR-1A derivatives, including fluorescent and photoaffinity-based probes, allowed quantification of IOR-1A, localization studies within S. rosetta cells, and evaluation of structure-activity relations. In a proof of concept study, an inhibitory bifunctional probe was employed in proteomic profiling studies, which allowed to deduce binding partners in bacteria and S. rosetta. These results showcase the power of synthetic chemistry to decipher the biochemical basis of cell differentiation processes within S. rosetta.

Design, synthesis, spectroscopic characterizations, in vitro pancreatic lipase as well as tyrosinase inhibition evaluations and in silico analysis of novel aryl sulfonate-naphthalene hybrids

One of the primary purposes of this study is to synthesize new aryl sulfonate-naphthalene hybrid structures possessing divergent electron-withdrawing and electron-releasing functional groups. Following the improved reaction conditions, we successfully gathered ten distinct sulfonate derivatives (3a-j) with good yields. The synthesized naphthalene-based sulfonate derivatives were then characterized using appropriate analytical methods (FT-IR, 1H-NMR, 13C-NMR, HRMS, and elemental analysis). Additionally, in vitro and in silico enzyme inhibitory properties of the prepared aryl sulfonate-naphthalene hybrid structures were evaluated against pancreatic lipase and tyrosinase enzymes. Corresponding in vitro enzyme activity investigations revealed that the produced compounds inhibit pancreatic lipase and tyrosinase enzymes significantly. According to the lowest IC50 values, 3h (95.3 ± 4.0 µM) demonstrated the most effective inhibition against pancreatic lipase, whereas 3a (40.8 ± 3.3 µM) was found as the most effective inhibition against the tyrosinase. According to in silico studies, 3a exhibited the highest affinity value (−9.9 kcal/mol) against pancreatic lipase, whereas 3f demonstrated the best affinity value (−8.7 kcal/mol) against tyrosinase. Furthermore, we investigated various structural and physicochemical properties of the target molecules, namely frontier orbital’ (HOMO, LUMO, and bandgap) energies (including their corresponding contour plots), global reactivity descriptors (ionization energy and electron affinity), and electronegativity values gathered from ground-state (GS) density functional theory (DFT) calculations. These investigations demonstrated that the observed electrostatic interactions effectively contributed to the studied molecules’ experimentally demonstrated enzyme inhibition potential. Also, ADMET studies were evaluated to enlighten the molecular interactions of the compounds with the enzymes. Communicated by Ramaswamy H. Sarma

Synthesis, characterization, evaluation of metabolic enzyme inhibitors and in silico studies of thymol based 2-amino thiol and sulfonic acid compounds

Eight new aminothiols (4a-g and 5) and three new sulfonic acid derivatives (6a-c) were synthesized, and their structures were characterized. Inhibitory effects of the obtained compounds on carbonic anhydrase I and II isoforms (hCA I and hCA II), butyrylcholinesterase (BChE) and acetylcholinesterase (AChE), enzymes were investigated. The newly synthesized compounds have inhibited hCA I with Kis ranging from 7.11 ± 1.46 nM (6a) to 670.52 ± 300.41 nM (4b) and, hCA II with Kis ranging from 16.83 ± 5.72 nM (6a) to 453.34 ± 208.56 nM (4c). Acetazolamide was employed as the positive control for both hCA isoforms (Ki for hCA I 198.81 ± 14.13 nM and Ki for hCA II 211.42 ± 13.10 nM), and among the new compounds obtained, it was observed that there were compounds that were active at much lower nM levels. All compounds were also evaluated for inhibition of AChE and BChE. They inhibited AChE and BChE enzymes in the range of Ki 5.24 ± 2.27 (6c) - 48.44 ± 21.82 (4g) for AChE and 4.86 ± 0.64 (6c) - 51.75 ± 12.56 (4a) for BChE, and the results were compared with the standard inhibitor Tacrine (Ki: 14.20 ± 8.83 nM toward AChE and Ki: 3.39 ± 1.91 nM for BChE). Cholinesterase (BChE and AChE) inhibitory abilities of all synthesized molecules were also performed in situ and molecular docking and molecular dynamics (MD) simulation studies. The molecular coupling scores of the compounds and the free binding energies calculated by MM/GBSA were found to be compatible. Examining the results obtained from this study shows that it may have the potential to develop new drugs to treat some global patients such as glaucoma and Alzheimer's disease (AD).

Synthesis of Hinokitiol Sulfonate Derivatives and Their Anti-Oomycete and Nematicidal Activities.

In order to explore novel natural product-based anti-oomycete and nematicidal agents, sixteen unreported 2-sulfonyloxyhinokitiol derivatives were prepared using the principle of active splicing, and structurally confirmed by proton nuclear magnetic resonance (1 H-NMR), carbon-13 nuclear magnetic resonance (13 C-NMR), high-resolution mass spectrometry (HRMS), and melting point. Moreover, we evaluated the title compounds as anti-oomycete and nematicidal agents against two serious agricultural pests of Phytophthora capsici and Meloidogyne incongnita. Among the sixteen hinokitiol esters tested: (1) Compounds 3a and 3m exhibited the most potent anti-oomycete activity compared to zoxamide against P. capsici, and the median effective concentration (EC50 ) values of 3a, 3m, and zoxamide were 18.64, 21.11, and 23.15 mg/L, respectively; Further studies showed that the existence of seven membered ring and carbonyl group was the necessary condition for the high anti-oomycete activity of hinokitiol. (2) Compounds 3n and 3p exhibited more promising nematicidal activity than hinokitiol, and the median lethal concentration (LC50 ) values of 3n, 3p and 1 against M. incongnita were 0.2111, 0.2079, and 0.3933 mg/L, respectively. This result will pave the way for further modification of hinokitiol to develop potential new fungicides and nematicides.

Sulfonic Acid Derivatives in the Production of Stable Co-Amorphous Systems for Solubility Enhancement

Co-amorphization is a promising approach to stabilize drugs in the amorphous form. Olanzapine, a poorly water-soluble drug was used in this study. Sulfonic acids (saccharin, cyclamic acid and acesulfame), free and in salt forms, were used as co-formers and compared with carboxylic acids commonly used in the preparation of co-amorphous systems. Several manufacturing techniques were tested, and the co-amorphous systems characterized by differential scanning calorimetry, X-ray powder diffraction, thermogravimetry and Fourier-transform infrared spectroscopy. Free sulfonic acids produced co-amorphous systems with the drug, unlike their salts. Spectroscopy data suggests the formation of salts between olanzapine and the sulfonic acids, used as co-formers. The co-amorphous system produced with saccharin by solvent evaporation, showed the most notable solubility enhancement (145 times). The stability of amorphous and co-amorphous olanzapine systems was assessed upon exposure to stress conditions during storage. Amorphized olanzapine readily reconverted back to the crystalline form while sulfonic acids:olanzapine co-amorphous were stable for up to 24 weeks in low/medium humidity conditions (11-75% RH). Results highlight the potential advantages offered by sulfonic acids as co-formers to produce stable and more soluble co-amorphous olanzapine.

Synthesis of Metalorganic Copolymers Containing Various Contorted Units and Iron(II) Clathrochelates with Lateral Butyl Chains: Conspicuous Adsorbents of Lithium Ions and Methylene Blue.

We report the synthesis of three highly soluble metalorganic copolymers, TCP1–3, that were made from a one-pot complexation of iron(II) clathrochelate units that are interconnected by various thioether-containing contorted groups. TCP1–3 were converted into their poly(vinyl sulfone) derivatives OTCP1–3 quantitatively via the selective oxidation of the thioether moieties into their respective sulfones. All of the copolymers, TCP1–3 and OTCP1–3, underwent structural analysis by various techniques; namely, 1H- and 13C-nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and gel permeation chromatography (GPC). The copolymers were tested as potent lithium ions adsorbents revealing a maximum adsorption (qm) value of 2.31 mg g−1 for OTCP2. Furthermore, this same copolymer was found to be a promising adsorbent of methylene blue (MEB); an isothermal adsorption study divulged that OTCP2’s uptake of MEB from an aqueous solution (following the Langmuir model) was, at maximum adsorption capacity, (qm) of 480.77 mg g−1; whereas the kinetic study divulged that the adsorption follows pseudo second-order kinetics with an equilibrium adsorption capacity (qe,cal) of 45.40 mg g−1.

Synthesis and antifungal/anti-oomycete activity of novel camphor-based sulfonate derivatives as potential SDH inhibitors

In this work, fourteen novel sulfonate derivatives 3a-3n bearing camphor scaffold were designed, synthesized and characterized by 1H-NMR, 13C-NMR, HR-MS and FT-IR spectra. The crystal structure of compound 3b was determined by X-ray diffraction analysis. In the preliminary antifungal activity bioassay, the title compounds presented moderate to prominent antifungal activity toward five crop pathogenic fungi and two crop pathogenic oomycetes. Among them, compound 3k exhibited prominent in vitro and in vivo antifungal activity toward P. capsici. The primary fungicide mechanism showed that 3k had a good capacity to destroy the surface morphology of P. capsici and interfere with the mycelial growth. Further, compound 3k exhibited potent SDH inhibitory activity with IC50 value of 0.66 µM, which was superior to carboxin (IC50 = 3.63 µM). Molecular docking results revealed that compound 3k well docked into the active site of SDH. These results indicated that compound 3k could be a novel monoterpene-derived SDHI inhibitor and is worthy of further study as a promising lead for fungicide development.

Distribution and metabolism of daidzein and its benzene sulfonates in vivo (in mice) based on MALDI-TOF MSI.

Daidzein (D1) has been proved to be of great benefit to human health. More and more attention was paid to the metabolic process of D1. Most studies focused on the metabolites of D1 and analogs were determined through the excretion of animals and humans by traditional HPLC-MS, while their in situ distribution and metabolism in organs in vivo has not been reported. In our group, novel daidzein sulfonate derivatives were synthesized and confirmed to have excellent pharmaceutical properties. They exhibited good anti-inflammatory, inhibitory activities on human vascular smooth muscle cell proliferation and other bioactivities. Compared with traditional analytical methods, matrix-assisted laser desorption ionization time-of-flight mass spectrometry imaging (MALDI-TOF MSI) can directly analyze the distribution of compounds in tissues and organs. In this study, we investigate the in situ distribution and metabolism of D1 and its derivatives (DD2, DD3) in the organs of mice based on MALDI-TOF MSI for the first time. Trace prototype compounds were detected in the plasma 4 h after the intravenous injection of D1, DD2, and DD3. Seven phase I metabolites and seven phase II metabolites were detected. D1 sulfates were found in the plasma and in organs except the heart. The presence of D1 and DD3 monosulfates in the brain indicated that they could penetrate the blood–brain barrier. DD2 and DD3 could be hydrolyzed into D1 and their metabolic pathways were similar to those of D1. In addition, a ligand-receptor docking of D1 and DD2 with mitogen-activated protein kinase 8 (JNK1) was performed because of their significant anti-inflammatory activities through the JNK signaling pathway. It showed that the binding energy of DD2 with JNK1 was obviously lower than that of D1 which was consistent with their anti-inflammatory activities. It provided a theoretical basis for further validation of their anti-inflammatory mechanism at the protein level. In summary, the research will provide beneficial guidance for further pharmacological, toxicological studies and the clinical-use research of these compounds.

Synthesis of (E)‐β‐Iodovinyl Sulfones via Photoredox Catalyzed Difunctionalization of Terminal Alkynes

AbstractA photoredox mediated approach enabling the synthesis of (E)‐β‐iodovinyl sulfones at room temperature using simple alkynes and thiols as the coupling partners in the presence of TBAI as iodine source is reported. The direct conversion of thiols into sulfones following the tandem introduction of C−I and C−S bonds is achieved using SeO2 as an oxidizing agent. The method is viable with a wide range of alkynes and thiols at room temperature, employs mild conditions, and has good yields. Besides, we could also use β‐iodovinyl sulfones as the starting material to access different β‐functionalized sulfone derivatives.

Study of Novel Furocoumarin Derivatives on Anti-Vitiligo Activity, Molecular Docking and Mechanism of Action.

Vitiligo is a common chronic dermatological abnormality that afflicts tens of millions of people. Furocoumarins isolated from Uygur traditional medicinal material Psoralen corylifolia L. have been proven to be highly effective for the treatment of vitiligo. Although many furocoumarin derivatives with anti-vitiligo activity have been synthesized, their targets with respect to the disease are still ambiguous. Fortunately, the JAKs were identified as potential targets for the disease and its inhibitors have been proved to be effective in the treatment of vitiligo in many clinical trials. Thus, sixty-five benzene sulfonate and benzoate derivatives of furocoumarins (7a–7ad, 8a–8ag) with superior anti-vitiligo activity targeting JAKs were designed and synthesized based on preliminary research. The SAR was characterized after the anti-vitiligo-activity evaluation in B16 cells. Twenty-two derivatives showed more potent effects on melanin synthesis in B16 cells than the positive control (8-MOP). Among them, compounds 7y and 8 not only could increase melanin content, but they also improved the catecholase activity of tyrosinase in a concentration-dependent manner. The docking studies indicated that they were able to interact with amino acid residues in JAK1 and JAK2 via hydrogen bonds. Furthermore, candidate 8 showed a moderate inhibition of CXCL−10, which plays an important role in JAK–STAT signaling. The RT-PCR and Western blotting analyses illustrated that compounds 7y and 8 promoted melanogenesis by activating the p38 MAPK and Akt/GSK-3β/β-catenin pathways, as well as increasing the expressions of the MITF and tyrosinase-family genes. Finally, furocoumarin derivative 8 was recognized as a promising candidate for the fight against the disease and worthy of further research in vivo.

Thiapillar[6]arene: Synthesis, Functionalization, and Properties

AbstractThe design and synthesis of new macrocycles with well-defined cavities represent a promising avenue for the development of new supramolecular hosts. Moreover, the ability to diversify a macrocycle through chemical manipulations enables the fine-tuning and tailoring of properties. In this report, the synthesis and functionalization of thiapillar[6]arene, a pillar[6]arene analogue in which the bridging methylene groups are replaced by sulfurs, are described. First, we demonstrate the scalable synthesis of the parent thiapillar[6]arene. Next, the diversification of thiapillar[6]arene is demonstrated via functionalization of the phenols and oxidation of the sulfur atoms. The solid-state structures of two thiapillar[6]arene derivatives are reported, and the effect of sulfur oxidation state on the macrocyclic conformation is discussed. All sulfone derivatives described were found to demonstrate high luminescence quantum yields (ΦF = 0.43–0.66) in CH2Cl2 with emission maxima between λ = 404 and 462 nm. Lastly, assessment of the electrochemical properties of the sulfone derivatives by square-wave voltammetry revealed electron-accepting ability owing to the oxidation of the sulfur atoms, with four reduction events observed for the analogues surveyed. Overall, this work implicates thiapillar[6]arene as a modular scaffold amenable for further applications in host–guest chemistry and sensing.

A colorimetric method to measure in vitro nitrogenase functionality for engineering nitrogen fixation

Biological nitrogen fixation (BNF) is the reduction of N2 into NH3 in a group of prokaryotes by an extremely O2-sensitive protein complex called nitrogenase. Transfer of the BNF pathway directly into plants, rather than by association with microorganisms, could generate crops that are less dependent on synthetic nitrogen fertilizers and increase agricultural productivity and sustainability. In the laboratory, nitrogenase activity is commonly determined by measuring ethylene produced from the nitrogenase-dependent reduction of acetylene (ARA) using a gas chromatograph. The ARA is not well suited for analysis of large sample sets nor easily adapted to automated robotic determination of nitrogenase activities. Here, we show that a reduced sulfonated viologen derivative (S2Vred) assay can replace the ARA for simultaneous analysis of isolated nitrogenase proteins using a microplate reader. We used the S2Vred to screen a library of NifH nitrogenase components targeted to mitochondria in yeast. Two NifH proteins presented properties of great interest for engineering of nitrogen fixation in plants, namely NifM independency, to reduce the number of genes to be transferred to the eukaryotic host; and O2 resistance, to expand the half-life of NifH iron-sulfur cluster in a eukaryotic cell. This study established that NifH from Dehalococcoides ethenogenes did not require NifM for solubility, [Fe-S] cluster occupancy or functionality, and that NifH from Geobacter sulfurreducens was more resistant to O2 exposure than the other NifH proteins tested. It demonstrates that nitrogenase components with specific biochemical properties such as a wider range of O2 tolerance exist in Nature, and that their identification should be an area of focus for the engineering of nitrogen-fixing crops.