Discovery of novel NF-кB inhibitor based on scaffold hopping: 1,4,5,6,7,8-hexahydropyrido[4,3-d]pyrimidine

Discovery of anti-inflammatory agents from 3, 4-dihydronaphthalene-1(2H)-one derivatives by inhibiting NLRP3 inflammasome activation

NLRP3 inflammatory vesicles are a polymer of cellular innate immunity composed of a pair of proteins. The continuous activation of NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammatory vesicles induces the occurrence and enhancement of inflammatory response. In this study, a series of 3, 4-dihydronaphthalene-1(2H)-one derivatives (DHNs, 6a-u, 7a-e, 8a-n) were synthesized and characterized by NMR and HRMS. We evaluated the cytotoxicity and anti-inflammatory activity of all compounds in vitro, and selected 7a substituted by 7-Br in A-ring and 2-pyridylaldehyde in C-ring as effective lead compounds. Specifically, 7a can block the assembly and activation of NLRP3 inflammasome by down-regulating the expression of NLPR3 and apoptosis-associated speck-like protein containing a CARD (ASC), and inhibiting the production of reactive oxygen species (ROS) and other inflammatory mediators. In addition, 7a inhibits the phosphorylation of inhibitor kappa B alpha (IκBα) and NF-κB/p65 and the nuclear translocation of p65, thereby inhibiting nuclear factor kappa-B (NF-κB) signaling. Molecular docking analysis confirmed that 7a could reasonably bind the active sites of NLRP3, ASC and p65 proteins. Therefore, 7a is predicted as a potential NLRP3 inflammatory vesicle inhibitor and deserves further research and development.

Discovery of anti-neuroinflammatory agents from 1,4,5,6-tetrahydrobenzo[2,3]oxepino[4,5-d]pyrimidin-2-amine derivatives by regulating microglia polarization

Neuroinflammation mediated by microglia activation leads to various neurodegenerative and neurological disorders. In order to develop more and better options for this disorders, a series of 3,4-dihydrobenzo[b]oxepin-5(2H)-one derivatives (BZPs, 6-19) and novel 1,4,5,6-tetrahydrobenzo[2,3]oxepino[4,5-d]pyrimidin-2-amine derivatives (BPMs, 20-33) were synthesized and screened the anti-neuroinflamamtion effects. 3,5-bis-trifluoromethylphenyl-substituted BPM 29 showed more potent anti-neuroinflammatory activity and no toxicity to BV2 microglia cells in vitro. 29 significantly reduced the number of M1 phenotype of microglia cells, but significantly increased the number of M2 phenotype of microglia cells in lipopolysaccharide (LPS)-induced BV2 microglia cells. 29 significantly reduced the secretion of inflammatory cytokines (IL-18, IL-1β, TNF-α), but increased the secretion of anti-inflammatory cytokines (IL-10) from LPS-induced BV2 microglia cells. Also, 29 inhibited the NOD-like receptor NLRP3 inflammasome formation, and down-regulated the expression of M2 isoform of pyruvate kinase in LPS-induced BV2 microglia cells. In vivo, 29 reduced the neuroinflammation in cuprizone-induced inflammatory and demyelinating mice by reducing the expression of inducible nitric-oxide synthase, but increased the expression of CD206. Taken together, 29 might be a prospective anti-neuroinflammatory compound for neuroinflammatory and demyelinating disease by alleviating microglia activation.

Development of Piperazine- and Oxazine-Linked Pyrimidines as p65 Subunit Binders of NF-κB in Human Breast Cancer Cells

Nuclear factor kappa B (NF-κB) is a potential therapeutic target in breast cancer. In the current study, a new class of oxazine- and piperazine-linked pyrimidines was developed as inhibitors of NF-κB, overcoming the complexity of the oxazine structure found in nature and enabling synthesis under laboratory conditions. Among the series of synthesized and tested oxazine-pyrimidine and piperazine-pyrimidine derivatives, compounds 3a and 5b inhibited breast cancer cell (MCF-7) viability with an IC50 value of 9.17 and 6.29 µM, respectively. In silico docking studies showed that the pyrimidine ring of 3a and the 4-methoxybenzyl thiol group of 5b could strongly bind the p65 subunit of NF-κB, with the binding energies -9.32 and -7.32 kcal mol-1. Furthermore, compounds 3a and 5b inhibited NF-κB in MCF-7 breast cancer cells. In conclusion, we herein report newer structures that target NF-κB in BC cells.

Synthesis of 1-(4-(Dimethylamino)phenyl)-3,4-diphenyl-1H-pyrrole-2,5-dione Analogues and their Anti-inflammatory Activities in Lipopolysaccharide-Induced BV2 Cells

A series of thalidomide analogues, where the fused benzene ring in the phthalimide moiety was converted into two separated diphenyl rings in maleimide moiety and N-aminoglutarimide moiety was replaced by substituted phenyl moiety, were synthesized and evaluated for their NO inhibitory activities on BV2 cells stimulated with lipopolysaccharide (LPS). Among the synthesized compounds, the dimethylaminophenyl analogue 1s (IC₅₀ = 7.1 μM) showed significantly higher inhibitory activity than the glutarimide analogue 1a (IC₅₀ > 50 μM) and suppressed NO production dose-dependently without cytotoxicity. In addition, 1s inhibited the production of pro-inflammatory cytokines and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) by blocking nuclear factor-kappa B (NF-κB) and p38 MAPK pathways. These results demonstrated that 1s showed good anti-inflammatory activity and could become a leading compound for the treatment of neuroinflammatory diseases.

1,4,5,6,7,8‑Hexahydropyrido[4,3‑d]pyrimidine inhibits HepG2 cell proliferation, migration and invasion, and induces apoptosis through the upregulation of miR‑26b‑5p by targeting CDK8

1,4,5,6,7,8-Hexahydropyrido[4,3-d]pyrimidine (PPM) promotes apoptosis of HepG2 cells and serves a role in tumor suppression. However, the role of microRNA (miRNA) regulation in initiating apoptosis remains unclear. Therefore, the present study performed reverse transcription-quantitative PCR to investigate the association between PPM and miRNA, which demonstrated that PPM upregulated the expression of miR-26b-5p. Wound healing and Transwell assays showed that PPM inhibited the migration and invasion of HepG2 cells, and EdU staining experiments showed that PPM inhibited the proliferation of HepG2 cells. Transfection with miR-26b-5p inhibitor reversed the effects of PPM on HepG2 cells. Flow cytometry results showed that PPM promoted apoptosis of HepG2 cells by upregulating miRNA (miR)-26b-5p, and Western blotting results showed that PPM promoted the expression of apoptosis-associated protein Bax and inhibited the expression of Bcl-2 by upregulating miR-26b-5p. Using a proteomic approach combined with bioinformatics analysis, CDK8 was identified as a potential target of miR-26b-5p and was downregulated by miR-26b-5p overexpression. However, PPM induced HepG2 cell cycle arrest without the involvement of miR-26b-5p. Western blotting results showed that PPM upregulation of miR-26b-5p suppresses NF-κB/p65 signaling pathway in HepG2 cells by targeting of CDK8. The present results suggested that miR-26b-5p may function as a target gene of PPM and may serve a role in hepatocellular carcinoma treatment.

Anti-inflammatory activity of fluorine-substituted benzo[h]quinazoline-2-amine derivatives as NF-κB inhibitors

Excessive inflammation can cause loss of tissue or organ function, leading to a number of chronic diseases and sometimes even death. Traditional treatment strategies for inflammation have mainly involved steroidal and non-steroidal anti-inflammatory drugs, but both have increasingly prominent side effects. Nuclear factor kappa B (NF-κB) inhibitors with anti-inflammatory properties and low toxicity are a new therapeutic strategy for the treatment of inflammatory diseases. To obtain novel NF-κB inhibitors, a series of 3,4-dihydronaphthalen-1(2H)-one derivatives (DHNs 6a-s), 1,4,5,6-tetrahydrobenzo[h]quinazolin-2-amine derivatives (BQAs 7a-c) and 5,6-dihydrobenzo[h]quinazolin-2-amine derivatives (BQAs 8a-p) were designed and synthesized, and characterized by NMR and HRMS. By evaluating toxicity and anti-inflammatory properties, fluorine-substituted 8c showed more potential anti-inflammatory activity and lower toxicity. 8c significantly reduced the phosphorylation of IκBα and p65, thereby inhibiting the NF-κB signaling pathway. In addition, 8c markedly decreased reactive oxygen species (ROS) production and downregulated the expression of NOD-like receptor pyrin domain-containing protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC) and cysteine aspartate protein hydrolase-1 (caspase-1). Therefore, compound 8c is expected to be a candidate compound for NF-κB inhibition and deserves further research and development.

Synthesis and bio-properties of 4-piperidone containing compounds as curcumin mimics

3,5-Diyliden-4-piperidone scaffold are considered as curcumin mimic exhibiting diverse bio-properties.

Discovery of anti-hepatoma agents from 1,4,5,6,7,8-hexahydropyrido[4,3-d]pyrimidine by inhibiting PI3K/AKT/NF-κB pathway activation

In order to obtain new anti-hepatoma drugs with low toxicity, some 1,4,5,6,7,8-hexahydropyrido[4,3-d]pyrimidines (PPMs, 4a-t) were synthesized in this study. Many of them showed significant anti-hepatoma effects against HCC cells and low toxicity toward HHL-5 cells. Combined with their anti-hepatoma activity and toxicity, 4-CF₃-substituted 4k was selected as an effective lead compound. Preliminary mechanistic studies revealed that 4k could up-regulate the expression levels of Bax and caspase-3 proteins, down-regulate the expression levels of Bcl-2 protein, promote significant apoptosis of HepG2, and block cells in G2-M phase to prevent cells from completing mitosis. Also, 4k could significantly inhibit the activation of PI3K/AKT/NF-κB pathway by blocking the phosphorylation of PI3K, AKT, NF-κB/p65 and IFN-γ-induced nuclear transport. Docking analysis showed that 4k could reasonably bind to the active sites of Bcl-2, NF-κB/p65, PI3K and AKT. This result suggested that 4k could be used as a new type of NF-κB inhibitor, which provides a scientific basis for further research into the treatment of hepatoma.

Crystal structure of (E)-7-fluoro-2-(3-fluorobenzylidene)-3,4-dihydronaphthalen-1(2H)-one, C17H12F2O1

C17H12F2O1, monoclinic, P 1 ‾ $P\overline{1}$ (no. 2), a = 7.3832(8) Å, b = 8.6467(9) Å, c = 11.3278(11) Å, α = 87.633(8)°, β = 88.022(8)°, γ = 65.364(10)°, V = 654.88(13) Å3, Z = 2, R gt (F) = 0.0369, wR ref (F 2) = 0.0987, T = 293(2) K.

Small molecule compounds with good anti-inflammatory activity reported in the literature from 01/2009 to 05/2021: a review

Inflammation and disease are closely related. Inflammation can induce various diseases, and diseases can promote inflammatory response, and two possibly induces each other in a bidirectional loop. Inflammation is usually treated using synthetic anti-inflammatory drugs which are associated with several adverse effects hence are not safe for long-term use. Therefore, there is need for anti-inflammatory drugs which are not only effective but also safe. Several researchers have devoted to the research and development of effective anti-inflammatory drugs with little or no side effects. In this review, we studied some small molecules with reported anti-inflammatory activities and hence potential sources of anti-inflammatory agents. The information was retrieved from relevant studies published between January 2019 and May, 2021 for review. This review study was aimed to provide relevant information towards the design and development of effective and safe anti-inflammation agents.

Crystal structure of (3E,5E)-1-(4-cyanobenzenesulfonyl)-3,5-bis(3-fluorobenzylidene)piperidin-4-one-dichloromethane (1/1), C27H20Cl2F2N2O3S

C27H20Cl2F2N2O3S, triclinic, P 1 ‾ $P‾{1}$ (no. 2), a = 8.7887(4) Å, b = 11.2517(6) Å, c = 13.7609(7) Å, α = 74.962(4)°, β = 81.084(4)°, γ = 71.259(4)°, V = 1240.68(11) Å3, Z = 2, R gt (F) = 0.0582, wR ref (F 2) = 0.1543, T = 100.0(1) K.

Crystal structure of (E)-2-((2-methoxy-3-pyridyl)methylene)-7-fluoro-3,4-dihydronaphthalen-1(2H)-one, C17H14FNO2

C17H14FNO2, monoclinic, P21/c (no. 14), a = 14.0279(13) Å, b = 7.0527(5) Å, c = 14.4150(16) Å, β = 113.165(12)°, V = 1311.2(2) Å3, Z = 4, Rgt (F) = 0.0524, wRref (F 2) = 0.1358, T = 100 K.

Crystal structure of (E)-2-(3,5-bis(trifluoromethyl)benzylidene)-7-methoxy-3,4-dihydronaphthalen- 1(2H)-one, C20H14F6O2

C 20 H 14 F 6 O 2 ${\text{C}}_{20}{\text{H}}_{14}{\text{F}}_{6}{\text{O}}_{2}$ , monoclinic, P21/c (no. 14), a = 14.791(2) Å, b = 8.5303(9) Å, c = 15.531(3) Å, β = 115.474(19)°, V = 1769.1(5) Å3, Z = 4, R g t ${R}_{gt}$ (F) = 0.0574, w   R ref $w\,{R}_{\text{ref}}$ (F 2) = 0.1451, T = 100 K.

CCDC no.: 2016723

Crystal structure of (E)-7-methoxy-2-((5-methoxypyridin-3-yl)methylene)-3,4- dihydronaphthalen-1(2H)-one, C18H17NO3

C18H17NO3, triclinic, P 1 ‾ $P‾{1}$ (no. 2), a = 7.3950(5) Å, b = 8.6697(5) Å, c = 11.6813(9) Å, α = 85.457(6)°, β = 76.712(6)°, γ = 82.759(5)°, V = 722.07(9) Å3, Z = 2, R gt (F) = 0.0502, wR ref (F 2) = 0.1342, T = 99.9(3) K.

Crystal structure of (3E,5E)-3,5-bis-4-methoxy-3-(trifluoromethyl)benzylidene)-1-methylpiperidin-4-one, C24H21F6NO3

C24H21F6NO3, monoclinic, P21/c (no. 14), a = 16.6493(9) Å, b = 15.3005(8) Å, c = 8.8554(5) Å, β = 99.746(6)°, V = 2223.3(2) Å3, Z = 4, R gt (F) = 0.0444, wR ref (F 2) = 0.1094, T = 100 K.