2080-33-3

In this work, we designed and synthesized 35 new triazolopyrimidine, pyrazolopyrimidine and quinoline derivatives as P. falciparum inhibitors (3D7 strain). Thirty compounds exhibited anti-P. falciparum activity, with IC50 values ranging from 0.030 to 9.1 μM. The [1,2,4]triazolo[1,5-a]pyrimidine derivatives were more potent than the pyrazolo[1,5-a]pyrimidine and quinoline analogues. Compounds 20, 21, 23 and 24 were the most potent inhibitors, with IC50 values in the range of 0.030–0.086 μM and were equipotent to chloroquine. In addition, the compounds were selective, showing no cytotoxic activity against the human hepatoma cell line HepG2. All [1,2,4]triazolo[1,5-a]pyrimidine derivatives inhibited PfDHODH activity in the low micromolar to low nanomolar range (IC50 values of 0.08–1.3 μM) and did not show significant inhibition against the HsDHODH homologue (0–30% at 50 μM). Molecular docking studies indicated the binding mode of [1,2,4]triazolo[1,5-a]pyrimidine derivatives to PfDHODH, and the highest interaction affinities for the PfDHODH enzyme were in agreement with the in vitro experimental evaluation. Thus, the most active compounds against P. falciparum parasites 20 (R = CF3, R1 = F; IC50 = 0.086 μM), 21 (R = CF3; R1 = CH3; IC50 = 0.032 μM), 23, (R = CF3, R1 = CF3; IC50 = 0.030 μM) and 24 (R = CF3, 2-naphthyl; IC50 = 0.050 μM) and the most active inhibitor against PfDHODH 19 (R = CF3, R1 = Cl; IC50 = 0.08 μM - PfDHODH) stood out as new lead compounds for antimalarial drug discovery. Their potent in vitro activity against P. falciparum and the selective inhibition of the PfDHODH enzyme strongly suggest that this is the mechanism of action underlying this series of new [1,2,4]triazolo[1,5-a]pyrimidine derivatives.

A series of sulfonamide derivatives were synthesized, and the enzyme inhibitory activity of the synthesized compounds on carbonic anhydrase II was evaluated. Through molecular docking studies, it was found that compounds 1b, 1e, 2a, 2b, 3a have a strong binding affinity to carbonic anhydrase II. The IC50 values of the four compounds 1e, 2b, 3a, and 3b were lower than that of the positive control drug acetazolamide. What’s more, the compounds had a high inhibitory activity for A549 lung cancer cell growth, among them, 1e and 3a could inhibit both carbonic anhydrase II and lung cancer cell proliferation.

GPR27 belongs, with GPR85 and GPR173, to a small subfamily of three receptors called “Super-Conserved Receptors Expressed in the Brain” (SREB). It has been postulated to participate in key physiological processes such as neuronal plasticity, energy metabolism, and pancreatic β-cell insulin secretion and regulation. Recently, we reported the first selective GPR27 agonist, 2,4-dichloro-N-(4-(N-phenylsulfamoyl)phenyl)benzamide (I, pEC50 6.34, Emax 100%). Here, we describe the synthesis and structure-activity relationships of a series of new derivatives and analogs of I. All products were evaluated for their ability to activate GPR27 in an arrestin recruitment assay. As a result, agonists were identified with a broad range of efficacies including partial and full agonists, showing higher efficacies than the lead compound I. The most potent agonist was 4-chloro-2,5-difluoro-N-(4-(N-phenylsulfamoyl)phenyl)benzamide (7y, pEC50 6.85, Emax 37%), and the agonists with higher efficacies were 4-chloro-2-methyl-N-(4-(N-phenylsulfamoyl)phenyl)benzamide (7p, pEC50 6.04, Emax 123%), and 2-bromo-4-chloro-N-(4-(N-phenylsulfamoyl)phenyl)benzamide (7r, pEC50 5.99, Emax 123%). Docking studies predicted the putative binding site and interactions of agonist 7p with GPR27. Selected potent agonists were found to be soluble and devoid of cellular toxicity within the range of their pharmacological activity. Therefore, they represent important new tools to further characterize the (patho)physiological roles of GPR27.

Indoleamine 2,3-dioxygenase 1 (IDO1) as a key rate-limiting enzyme in the kynurenine pathway of tryptophan metabolism plays an important role in tumour immune escape. Herein, a variety of secondary sulphonamides were synthesised and evaluated in the HeLa cell-based IDO1/kynurenine assay, leading to the identification of new IDO1 inhibitors. Among them, compounds 5d, 5l and 8g exhibited the strongest inhibitory effect with significantly improved activity over the hit compound BS-1. The in vitro results showed that these compounds could restore the T cell proliferation and inhibit the differentiation of na?ve CD4+ T cell into highly immunosuppressive FoxP3+ regulatory T (Treg) cell without affecting the viability of HeLa cells and the expression of IDO1 protein. Importantly, the pharmacodynamic assay showed that compound 5d possessed potent antitumour effect in both CT26 and B16F1 tumours bearing immunocompetent mice but not in immunodeficient mice. Functionally, subsequent experiments demonstrated that compound 5d could effectively inhibit tumour cell proliferation, induce apoptosis, up-regulate the expression of IFN-γ and granzyme B, and suppress FoxP3+ Treg cell differentiation, thereby activate the immune system. Thus, compound 5d could be a potential and efficacious agent for further evaluation.

The rapid emergence of antibiotic-resistant Gram-negative bacteria (GNB) is becoming a global healthcare concern, and it urgently needs novel strategies to match the clinical challenge. In this work, we conjugated chitosan (CS) with LED 209, a highly selective inhibitor of QseC of GNB, to create the novel selective antimicrobial agent CS/LED. The data of FT-IR, NMR and elemental analysis for CS/LED conjugates proved the successful conjugation of CS with LED 209. Interestingly, the fluorescence signal detected in MDR-E. coli of CS/LED-FITC was about 2 times than that of CS-FITC at 3 h. The results shown that compared with CS, CS/LED exhibited higher selective antimicrobial on MDR-E. coli. Moreover, CS/LED exhibited the lower selectivity and cytotoxicity to mammalian cell than CS. Additionally, an unexpected enhancement of anti-adhesion activity against MDR-E. coli was determined by cellulose membrane coating CS/LED. The results demonstrated that CS/LED could reduce the adhesion of bacteria to the cellulose membrane by about 67.8%, while CS only reduced by about 45.3%. The dressings coated with CS/LED possessed the stronger ability to prevent microbial adhesion compared to the CS-coated dressing. Our present work firstly demonstrated that CS/LED had a highly selective activity and anti-adhesion activity against MDR-E. coli, which offered a potent and selective antimicrobial for combating multidrug-resistant GNB infections.

A newly developed chemoselective reaction of sodium arylsulfinates or arylsulfonyl chlorides with nitroarenes has been disclosed. The chemistry, in which non-toxic water and recyclable iron-based metal-organic frameworks are employed as the solvent and catalyst, respectively, provides an efficient approach for the generation of N-arylsulfonamides, which are widely present in biologically active compounds and drugs, rendering this methodology attractive to both synthetic and medicinal chemistry.

The well-known and rapidly growing phenomenon of bacterial resistance to antibiotics is caused by uncontrolled, excessive and inappropriate use of antibiotics. One of alternatives to antibiotics is Photodynamic Antibacterial Chemotherapy (PACT). In the present study, the effect of PACT using a photosensitizer Rose Bengal alone and in combination with antibiotics including methicillin and derivatives of sulfanilamide synthesized by us was tested against antibiotic-sensitive and antibiotic-resistant clinical isolates of Gram-positive S. aureus and Gram-negative P. aeruginosa. Antibiotic-sensitive and resistant strains of P. aeruginosa were eradicated by Rose Bengal under illumination and by sulfanilamide but were not inhibited by new sulfanilamide derivatives. No increase in sensitivity of P. aeruginosa cells to sulfanilamide was observed upon a combination of Rose Bengal and sulfanilamide under illumination. All tested S. aureus strains (MSSA and MRSA) were effectively inhibited by PACT. When treated with sub-MIC concentrations of Rose Bengal under illumination, the minimum inhibitory concentrations (MIC) of methicillin decreased significantly for MSSA and MRSA strains. In some cases, antibiotic sensitivity of resistant strains can be restored by combining antibiotics with PACT.

Nicotinamide adenine dinucleotide (NAD+) synthetase catalyzes the last step in NAD+ biosynthesis. Depletion of NAD+ is bactericidal for both active and dormant Mycobacterium tuberculosis (Mtb). By inhibiting NAD+ synthetase (NadE) from Mtb, we expect to eliminate NAD+ production which will result in cell death in both growing and nonreplicating Mtb. NadE inhibitors have been investigated against various pathogens, but few have been tested against Mtb. Here, we report on the expansion of a series of urea-sulfonamides, previously reported by Brouillette et al. Guided by docking studies, substituents on a terminal phenyl ring were varied to understand the structure–activity-relationships of substituents on this position. Compounds were tested as inhibitors of both recombinant Mtb NadE and Mtb whole cells. While the parent compound displayed very weak inhibition against Mtb NadE (IC50 = 1000 μM), we observed up to a 10-fold enhancement in potency after optimization. Replacement of the 3,4-dichloro group on the phenyl ring of the parent compound with 4-nitro yielded 4f, the most potent compound of the series with an IC50 value of 90 μM against Mtb NadE. Our modeling results show that these urea-sulfonamides potentially bind to the intramolecular ammonia tunnel, which transports ammonia from the glutaminase domain to the active site of the enzyme. This hypothesis is supported by data showing that, even when treated with potent inhibitors, NadE catalysis is restored when treated with exogenous ammonia. Most of these compounds also inhibited Mtb cell growth with MIC values of 19–100 μg/mL. These results improve our understanding of the SAR of the urea-sulfonamides, their mechanism of binding to the enzyme, and of Mtb NadE as a potential antitubercular drug target.

The present invention relates to compounds and methods for the treatment of bacterial infections. Because their mechanism of action does not involve killing of bacteria or inhibiting their growth, the potential for these compounds to induce drug resistance in bacteria is minimized. Through inhibiting bacterial virulence, the present invention provides a novel means of treating bacterial infections.

The sulfonylation reaction of various aliphatic, alicyclic, aromatic, and hetero-aromatic amines with p-acetamidobenzenesulfonyl chloride has been investigated using different types of base catalysis under varied reaction conditions. Mg–Al hydrotalcite, characterizable as an inexpensive, reusable, and green solid catalyst, was found to be the most efficient catalyst, when the reaction is carried out in a minimum volume of solvent (acetone). The reaction was found to be accelerated drastically with the support of ultrasound irradiation, affording the sulfonamides in yields better or equivalent to those obtained under the longer lasting conventional stirring conditions.

One-step, catalytic synthesis of N-arylsulfonamides via the construction of N-S bonds from the direct coupling of sodium arylsulfinates with nitroarenes was realized in the presence of FeCl2 and NaHSO3 under mild conditions. In this process, stable and readily available nitroarenes were used as nitrogen sources, and NaHSO3 acted as a reductant to provide N-arylsulfonamides in good to excellent yields. A broad range of functional groups were very well-tolerated in this reaction system. In addition, mechanistic studies indicated that the N-S bond might be generated through direct coupling of nitroarene with sodium arylsulfinate prior to the reduction of nitroarenes by NaHSO3. Accordingly, a reaction mechanism involving N-aryl-N-arenesulfonylhydroxylamine as an intermediate was proposed.

Four sulfanilamide derivatives N-[4-(phenylsulfamoyl)phenyl]acetamide (1), 4-amino-N-phenylbenzenesulfonamide (2), N-[4-(phenylsulfamoyl)phenyl]benzamide (3) and N-{4-[(3-chlorophenyl)sulfamoyl]phenylbenzamide (4) were synthesized and characterized by Infra-Red (IR), Nuclear Magnetic Resonance (NMR) and UV-visible (UV-Vis) spectra. Also Liquid Chromatographic (LCMS) and High Resolution Mass Spectrometric (HRMS) methods were used. Crystal structures of 1-4 were determined by single crystal X-ray diffraction (XRD) and their conformational and hydrogen bond (HB) network properties were examined with survey of the literature data. Compounds 1 and 2 crystallize in the same orthorhombic Pbca symmetry with equivalent molecular conformation (tilted V-shape) but showed distinct packing and hydrogen bonding models. Compounds 3 and 4 crystallize in monoclinic and triclinic crystal systems, albeit exhibiting identical molecular conformation (L-shaped). Same donor acceptor pairs both on 3 and 4 result to different kind of HB network. Thermogravimetric (TG) and differential scanning calorimetric (DSC) methods were used to evaluate thermal properties of the substances. All sulfanilamide derivatives have melting points between195-227 C, initiation of thermal decomposition between 259-271 C and enthalpies of fusion ΔHfusT = 38.96, 36.60, 46.23 and 44.81 kJ mol -1 were determined for 1-4, respectively. The derivatives were screened for their antibacterial and antifungal activities against various bacterial and fungal strains. It is observed that there is no significant antibacterial activity with the introduction of the benzene ring to CO-NH group or SO2-NH moiety, and none of the compounds exhibited antifungal activity.

Four series of forty-five nitrogen-containing polyhydroxylated aromatics based on caffeic acid phenethyl ester were designed and synthesized as HIV-1 integrase (IN) inhibitors. Most of these compounds inhibited IN catalytic activities in low micromolar range. Among these new analogues, compounds 9e and 9f were the most potent IN inhibitors with IC50 value of 0.7 μM against strand transfer reaction. Their key structure-activity relationships were also discussed.

The reaction of 3-chloropyridazine 1 with N -(un)Substituted 4-aminosulfonamides 3 gave the 3-substituted aminopyridazines 4. Also In addition, pyridazine-3-sulfonamides 7 were prepared from the reaction of pyridazine-3-sulfonylchloride 6 with different amines. All of these derivatives have been characterized by analytical and spectroscopic studies, and also were tested for their in vitro antibacterial and antifungal activity against a variety of microorganisms.

A series of nitrogen-containing polyhydroxylated aromatics from caffeic acid phenethyl ester were designed and synthesized as HIV-1 integrase inhibitors. Most of these compounds exhibited potent inhibitory activities at micromolar concentrations against HIV-1 integrase in the 3′-end processing and the strand transfer. Their key structure-activity relationship was also discussed.

The preparation of N-acylsulfonamides is described using primary amines, arylsulfonyl chlorides and acyl chlorides. Reaction of primary aryl amines with arylsulfonyl chlorides in the presence of NaHCO3 produced N-arylsulfonamides, which reacted in situ with benzoyl chloride furnishing the corresponding N-benzoyl-N-arylsulfonamides in 72-96% yields. Accordingly, 4-nitrobenzoyl chloride and 3,5-dinitrobenzoyl chloride were used as acylating agents. All the reactions were carried out under solvent-free conditions at room temperature and the products were isolated after simple work-up in high yields and purity.

Sulfonamides are viable replacements for the phenylsulfonyl and benzoyl moieties initially described for the anilide tertiary carbinol series of K(ATP) potassium channel openers. The SAR of this new series and the synthetic chemistry employed to generate its members are described.

N-Aryl-substituted 3(4)-aminobenzenesulfonamides were synthesized.They are the starting compounds for the production of the corresponding substituted 3(4)-(3-methyl-5-oxo-2-pyrazolin-1-yl)-N-phenylbenzenesulfonamides.Data from the IR, PMR, and mass spectra are presented, and the fragmentation of the molecules is discussed.

2,4-Dichloro, 2,5-dichloro and 3,4-dichloro-benzene-sulfanilides react with chlorosulfonic acid at low temperature to give good yields of the corresponding dichlorobenzenesulfonyl sulfanilyl chlorides.A number of chlorides have been converted into derivatives by reaction with nucleophiles, such as dimethylamine, hydrazine and sodium azide.N4-Acetamidobenzenesulfonylsulfanilyl derivatives have been prepared by the condensation of N4-acetylsulfanilyl chloride with the appropriate sulfanilyl derivative.Methylsulfonanilide reacts with chlorosulfonic acid to give N4-(methylsulfonyl)sulfanilyl chloride.The compounds have been tested for their antibacterial and antifungal activity.