Evaluation of the Inhibitory Effects of Pyridylpyrazole Derivatives on LPS-Induced PGE2 Productions and Nitric Oxide in Murine RAW 264.7 Macrophages

A series of thirteen triarylpyrazole analogs were investigated as inhibitors of lipopolysaccharide (LPS)-induced prostaglandin E₂ (PGE₂) and nitric oxide (NO) production in RAW 264.7 macrophages. The target compounds 1a-m have first been assessed for cytotoxicity against RAW 264.7 macrophages to determine their non-cytotoxic concentration(s) for anti-inflammatory testing to make sure that the inhibition of PGE₂ and NO production would not be caused by cytotoxicity. It was found that compounds 1f and 1m were the most potent PGE₂ inhibitors with IC₅₀ values of 7.1 and 1.1 μM, respectively. In addition, these compounds also showed inhibitory effects of 11.6% and 37.19% on LPS-induced NO production, respectively. The western blots analysis of COX-2 and iNOS showed that the PGE₂ and NO inhibitory effect of compound 1m are attributed to inhibition of COX-2 and iNOS protein expression through inactivation of p38.

Therapeutic potential for coxibs-nitric oxide releasing hybrids in cystic fibrosis

This review discusses the rational for further studies of COX-2 inhibitors-NO releaser hybrids (NO-Coxibs) in the pharmacological treatment of the airway inflammation in Cystic Fibrosis (CF). Our research group developed several classes of NO-Coxibs for the pharmacological treatment of arthritis, and among them several compounds showed an outstanding in vivo efficacy and good pharmacokinetic properties. The good antiinflammatory properties displayed by these compounds during the previous screening could, by itself, suggest appropriate candidates for further testing in CF.

Transition-metal-free regioselective construction of 1,5-diaryl-1,2,3-triazoles through dehydrative cycloaddition of alcohols with aryl azides mediated by SO2F2

A novel, simple and practical method for mild, efficient, cost-effective and regioselective synthesis of highly valuable 1,5-diaryl-1,2,3-triazoles was achieved through dehydrative annulation of readily available alcohols with aryl azides. The reaction proceeded at room temperature, without any metal catalysts, exhibiting excellent compatibility to a large variety of functional groups (>50 examples), resulting in up to quantitative yields.

Screening of NO Inhibitor Release Activity from Soft Coral Extracts Origin Palu Bay, Central Sulawesi, Indonesia

BACKGROUND

As a marine organism, soft corals can be utilized to be various bioactive substances, especially terpenoids and steroids. The soft corals family which produces bioactive generally come from clavulariidae, alcyoniidae, nephtheidae and xeniidae family.

OBJECTIVE

To investigate the bioactivity of Nitric Oxide (NO) inhibitor release from soft coral crude extracts of Sinularia sp. (SCA), Nephthea sp. (SCB), Sarcophyton sp. (SCC), Sarcophyton sp. (SCD), Sinularia sp. (SCE) and Sinularia sp. (SCF).

MATERIALS AND METHODS

Soft coral is collected from Palu Bay (Central Sulawesi). NO inhibitory release activity measured according to the Griess reaction. Soft corals sample macerated with 1:2 (w/v). Then, Soft coral extracts with the best NO Inhibitor activity partitioned with Dichloromethane, Ethyl acetate, and n-butanol. The bioactive of all crude extracts were identified by GC-MS to find compounds with anti-inflammatory potential.

RESULTS

Sarcophyton sp. (SCC) and Sinularia sp. (SCF) are able to inhibit NO concentrations of 0.22 ± 0.04 and 0.20 ± 0.04 µM at 20 mg/mL, respectively. The chemical constituents determined and showed the potential as anti-inflammatory in the crude of Sinularia sp. (SCA) were Octacosane (3.25%). In Nephthea sp., (SCB) were Cyclohexene, 6-ethenyl-6- methyl-1-(1-methylethyl)-3-(1-methylethylidene)-,(S)- (0.55%); Azulene, 1,2,3,4,5,6,7,8- octahydro-1,4-dimethyl-7-(1-methylethylidene)-, (1S-cis)- (0.53%); and 1,7,7-Trimethyl- 2-vinylbicyclo[2.2.1]hept-2-ene (4.72%). In Sarcophyton sp, (SCC) were Eicosane (0.12%); Nonacosane (10.7%); 14(β)-Pregnane (0.87%); Octacosane 6.39%); and Tricosane (1.53%). In Sarcophyton sp. (SCD) were 14(β)-Pregnane (2.69%); and Octadecane (27.43%). In crude of Sinularia sp. (SCE) were Oleic Acid (0.63%); 7,10-Hexadecadienoic acid, methyl ester (0.54%); 14(β)-Pregnane (1.07%); 5,8,11,14-Eicosatetraenoic acid, ethyl ester, (all-Z)- (4.60%); Octacosane (7.75%); and 1,2-Benzisothiazole, 3-(hexahydro-1Hazepin- 1-yl)-, 1,1-dioxide (1.23%). In the crude of Sinularia sp., (SCF) were Oxirane, decyl- (1.38%); Nonacosane (0.57%); Cyclohexanol, 5-methyl-2-(1-methylethenyl)- (0.61%); 14B-Pregnane (0.76%); and Tetratriacontane (1.02%).

CONCLUSION

The extract of Sarcophyton sp. (SCC) and Sinularia sp. (SCF) showed the best NO inhibitory release activity. This study is making soft corals from Central Sulawesi, Indonesia can become a potential organism in the discovery and development of bioactive substances anti-inflammatory.

Copper-catalyzed decarboxylative regioselective synthesis of 1,5-disubstituted 1,2,3-triazoles

A copper-catalyzed decarboxylative regioselective protocol for the synthesis of 1,5-disubstituted 1,2,3-triazoles via direct annulation of cinnamic acids with aryl azides has been developed. This is the first example of 1,5-disubstituted 1,2,3-triazoles using Cu(ii) as the catalyst, which were generally synthesized using a ruthenium(ii) catalyst.

Synthesis of New Tricyclic and Tetracyclic Fused Coumarin Sulfonate Derivatives and Their Inhibitory Effects on LPS-Induced Nitric Oxide and PGE2 Productions in RAW 264.7 Macrophages: Part 2

The synthesis of a new series of 21 fused coumarin derivatives is described, and the biological evaluation of their in vitro antiinflammatory effects as inhibitors of lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E₂ (PGE₂ ) production in RAW 264.7 macrophages. The target compounds 1a-u were first tested for cytotoxicity to determine a non-toxic concentration for antiinflammatory screening, so that the inhibitory effects against NO and PGE₂ production would not be caused by cytotoxicity. Compounds 1f and 1p were the most active PGE₂ inhibitors with IC₅₀ values of 0.89 and 0.95 µM, respectively. Western blot and cell-free COX-2 screening showed that their effects were due to inhibition of both COX-2 protein expression and COX-2 enzyme activity. Their IC₅₀ values against the COX-2 enzyme were 0.67 and 0.85 µM, respectively, which is more potent than etoricoxib. The selectivity indexes of compounds 1f and 1p against COX-2 compared to COX-1 were 41.1 and 42.5, respectively. Compound 1f showed strong inhibitory effects at 5 µM concentration on COX-2 mRNA expression in LPS-induced RAW 264.7 macrophages. Moreover, the tricyclic compounds 1l and 1n as well as the tetracyclic analog 1u were the most potent NO inhibitors, with one-digit micromolar IC₅₀ values. They showed dose-dependent inhibition of inducible nitric oxide synthase (iNOS) protein expression. The tetracyclic derivative 1u was the most potent inhibitor of NO production. It also exhibited a strong inhibitory effect on iNOS mRNA expression in LPS-induced RAW 264.7 macrophages.

Fluorophore-labeled cyclooxygenase-2 inhibitors for the imaging of cyclooxygenase-2 overexpression in cancer: synthesis and biological studies

A group of cyclooxygenase-2 (COX-2)-specific fluorescent cancer biomarkers were synthesized by linking the anti-inflammatory drugs ibuprofen, (S)-naproxen, and celecoxib to the 7-nitrobenzofurazan (NBD) fluorophore. In vitro COX-1/COX-2 inhibition studies indicated that all of these fluorescent conjugates are COX-2 inhibitors (IC₅₀ range: 0.19-23.0 μM) with an appreciable COX-2 selectivity index (SI≥4.3-444). In this study the celecoxib-NBD conjugate N-(2-((7-nitrobenzo[c][1,2,5]oxadiazol-4-yl)amino)ethyl)-4-(5-(p-tolyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl)benzenesulfonamide, which displayed the highest COX-2 inhibitory potency and selectivity (COX-2 IC₅₀ =0.19 μM; SI=443.6), was identified as an impending COX-2-specific biomarker for the fluorescence imaging of cancer using a COX-2-expressing human colon cancer cell line (HCA-7).

1,4-Diaryl-substituted triazoles as cyclooxygenase-2 inhibitors: Synthesis, biological evaluation and molecular modeling studies

A novel group of 1,4-diaryl-substituted triazoles was designed and synthesized by introducing the cyclooxygenase-2 (COX-2) pharmacophore SO2NH2 attached to one aryl ring and various substituents (H, F, Cl, CH3 or OCH3) attached to the other aryl ring. The effects of size and flexibility of the compounds upon COX-1/COX-2 inhibitory potency and selectivity was studied by increasing the size of an alkyl linker chain [(-CH2)n, where n=0, 1, 2]. In vitro COX-1/COX-2 inhibition studies showed that all compounds (14-18, 21-25 and 28-32) are more potent inhibitors of COX-2 isozyme (IC50=0.17-28.0μM range) compared to COX-1 isozyme (IC50=21.0 to >100μM range). Within the group of 1,4 diaryl-substituted triazoles, 4-{2-[4-(4-chloro-phenyl)-[1,2,3]triazol-1-yl]-ethyl}-benzenesulfonamide (compound 30) displayed highest COX-2 inhibitory potency and selectivity (COX-1: IC50=>100μM, COX-2: IC50=0.17μM, SI >588). Molecular docking studies using the catalytic site of COX-1 and COX-2, respectively, provided complementary theoretical support for the obtained experimental biological structure-activity relationship data. Results of molecular docking studies revealed that COX-2 pharmacophore SO2NH2 in compound 30 is positioned in the secondary pocket of COX-2 active site; with the nitrogen atom of the SO2NH2 group being hydrogen bonded to Q192 (N⋯OC=2.85Å), and one of the oxygen atoms of SO2NH2 group forming a hydrogen bond to H90 (SO⋯N=2.38Å).

A diazen-1-ium-1,2-diolate analog of 7-azabenzobicyclo[2.2.1]heptane: synthesis, nitric oxide and nitroxyl release, in vitro hemodynamic, and anti-hypertensive studies

1-(7-Azabenzobicyclo[2.2.1]heptane)diazen-1-ium-1,2-diolate (16) was designed with the expectation that it would act as a dual nitric oxide (NO) and nitroxyl (HNO) donor that is not carcinogenic or genotoxic. Compound 16, with a suitable half-life (17.8 min) in PBS at pH 7, released NO (19%) and HNO (22%) during a 2h incubation in PBS at pH 7. In addition, compound 16 exhibited a significant in vitro positive inotropic effect, increased the rates of contraction and relaxation, and increased coronary flow rate, but did not induce a chronotropic effect. Furthermore, compound 16 (13.7 mg kg(-1), po dose) provided a significant reduction in the blood pressure of mice up to 3h post-drug administration. All these data suggest that compound 16 constitutes an attractive 'lead-compound' that could have potential applications to treat cardiovascular disease(s) such as congestive heart failure.

O2-sulfonylethyl protected isopropylamine diazen-1-ium-1,2-diolates as nitroxyl (HNO) donors: synthesis, β-elimination fragmentation, HNO release, positive inotropic properties, and blood pressure lowering studies

New types of nonexplosive O(2)-sulfonylethyl protected (-CH(2)CH(2)SO(2)R; R = OMe, NHOMe, NHOBn, Me) derivatives of isopropylamine diazen-1-ium-1,2-diolate (IPA/NO) (2-5) were developed that are designed to act as novel HNO donors. These compounds, with suitable half-lives (6.6-17.1 h) at pH 7.4, undergo a base-induced β-elimination reaction that releases a methyl vinyl sulfone product and the parent IPA/NO anion which subsequently preferentially releases HNO (46-61% range). Importantly, the O(2)-methylsulfonylethyl compound 5 exhibited a significant in vitro inotropic effect up to 283% of the baseline value and increased the rates of contraction and relaxation but did not induce a chronotropic effect. Furthermore, compound 5 (22.5 mg/kg po dose) provided a significant reduction in blood pressure up to 6 h after drug administration. All these data suggest that O(2)-sulfonylethyl protected derivatives of IPA/NO, which are efficient HNO donors, could have potential applications to treat cardiovascular disease(s) such as congestive heart failure.