Hydroxyl-substituted double Schiff-base condensed 4-piperidone/cyclohexanones as potential anticancer agents with biological evaluation

A novel gemcitabine analog as a potential anticancer agent: synthesis and in-vitro evaluation against pancreatic cancer

Gemcitabine (Gem) is approved for use in pancreatic cancer chemotherapy. However, Gem undergoes rapid metabolism in the blood, producing an inactive metabolite. Due to this rapid metabolism, the effective dose of Gem is high, thereby predisposing patients to severe adverse effects. This study aimed to improve Gem's metabolic and therapeutic stability by modifying the amine group (4-NH2) with hydroxylamine to form 4-N-hydroxylGem hydrochloride (GemAGY). Micro-elemental analysis and Nuclear Magnetic Resonance (NMR) were used to characterize GemAGY, and its anticancer activity was investigated against MiaPaCa-2, BxPC-3, and PANC-1 pancreatic cancer cell lines. The GemAGY metabolic stability was evaluated in human liver microsomal solution. In the 2D cytotoxicity assay, the IC50 values of GemAGY-treated MiaPaCa-2, PANC-1, and BxPC-3 cells were significantly lower when compared to GemHCl-treated cultures. More so, in 3D spheroid assay results, GemAGY IC50 values were found to be 9.5 ± 1.1 µM and 12.6 ± 1.0 µM when compared to GemHCl IC50 values of 24.1 ± 1.6 µM and 30.2 ± 1.8 µM in MiaPaCa-2 and PANC-1 cells, respectively. GemAGY was stable, with 60% remaining intact after 2 hours of digestion in microsomal enzymes, compared to GemHCl, which had less than 45% remaining intact after 30 minutes. GemAGY-treated MiaPaCa-2 and PANC-1 cells at 3.12 and 6.25 μM concentrations demonstrated a significantly reduced cell migration towards the wound area compared to the GemHCl-treated cultures at the same concentrations. Further, GemAGY-treated MiaPaCa-2 cells significantly increased the expression of p53 and BAX compared to GemHCl-treated cells. GemAGY demonstrated significant anticancer activity and improved metabolic stability compared to GemHCl and is most likely to have potential anticancer activity against pancreatic cancer.

Crystal structure of (3E,5E)-3,5-bis(4-fluorobenzylidene)-1-((4-trifluoromethyl)benzenesulfonyl)piperidin-4-one, C26H18F5NO3S

C26H18F5NO3S, triclinic, P 1 ‾ $P‾{1}$ (no. 2), a = 7.8831(4) Å, b = 11.9591(7) Å, c = 13.3258(7) Å, α = 69.072(5)°, β = 88.556(4)°, γ = 73.730(5)°, V = 1122.48(11) Å3, Z = 2, R gt (F) = 0.0507, wR ref (F 2) = 0.1216, T = 100.0(1) K.

Trifluoromethyl-substituted 3,5-bis(arylidene)-4-piperidones as potential anti-hepatoma and anti-inflammation agents by inhibiting NF-кB activation

Some methoxy-, hydroxyl-, pyridyl-, or fluoro-substituted 3,5-bis(arylidene)-4-piperidones (BAPs) could reduce inflammation and promote hepatoma cell apoptosis by inhibiting activation of NF-κB, especially after introduction of trifluoromethyl. Herein, a series of trifluoromethyl-substituted BAPs (4-30) were synthesised and the biological activities were evaluated. We successfully found the most potential 16, which contains three trifluoromethyl substituents and exhibits the best anti-tumour and anti-inflammatory activities. Preliminary mechanism research revealed that 16 could promote HepG2 cell apoptosis in a dose-dependent manner by down-regulating the expression of Bcl-2 and up-regulating the expression of Bax, C-caspase-3. Meanwhile, 16 inhibited activation of NF-κB by directly inhibiting the phosphorylation of p65 and IκBα induced by LPS, together with indirectly inhibiting MAPK pathway, thereby exhibiting both anti-hepatoma and anti-inflammatory activities. Molecular docking confirmed that 16 could bind to the active sites of Bcl-2, p65, and p38 reasonably. The above results suggested that 16 has enormous potential to be developed as a multifunctional agent for the clinical treatment of liver cancers and inflammatory diseases.

Potential anti-neuroinflammatory NF-кB inhibitors based on 3,4-dihydronaphthalen-1(2H)-one derivatives

Nuclear factor kappa B (NF-кB) inhibition represents a new therapeutic strategy for the treatment of neuroinflammatory diseases. In this study, a series of 3,4-dihydronaphthalen-1(2H)-one (DHN; 6a-n, 7a-c) derivatives were synthesised and characterised by NMR and HRMS. We assessed the toxicity and anti-neuroinflammatory properties of these compounds and found that 6m showed the greatest anti-neuroinflammatory properties, with relatively low toxicity. Specifically, 6m significantly reduced reactive oxygen species production, down-regulated the expression of NOD-like receptor pyrin domain-containing protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), and caspase-1 and prevented lipopolysaccharide-stimulated BV2 microglia cells polarisation towards an M1 phenotype. Furthermore, 6m significantly decreased IκBα and NF-кB p65 phosphorylation, thus inhibiting the NF-кB signalling pathway. This suggests that 6m may be explored as a functional anti-neuroinflammatory agent for the treatment of inflammatory diseases in the central nervous system, such as multiple sclerosis, traumatic brain injury, stroke and spinal cord injury.

Antiproliferative Activity and Apoptotic Efficiency of Syzygium cumini Bark Methanolic Extract against EAC Cells In Vivo

BACKGROUND

Syzygium cumini is one of the evidence-based traditional medicinal plant used in the treatment of various ailments.

OBJECTIVES

Herein, the antioxidant property and anticancer property of Syzygium cumini against Ehrlich Ascites Carcinoma (EAC) cells were examined to find effective chemotherapeutics.

METHODS

In vitro assays, and phytochemical and chromatographic analyses were used to determine antioxidant properties and chemical constituents of Syzygium cummini Bark Methanolic Extract (SCBME). Functional assays were used to measure the anticancer activity of SCBME. Fluorescence microscopy and RT-PCR were used to examine morphological and molecular changes of EAC cells followed by SCBME treatment.

RESULTS

Phytochemical and GC-MS analyses confirmed the presence of compounds with antioxidant and anticancer activities. Accordingly, we have noted a strong antioxidant activity of SCBME with an IC₅₀ value of ~10μg/ml. Importantly, SCBME exerted a dose-dependent anticancer activity with significant inhibition of EAC cell growth (71.08±3.53%; p<0.001), reduction of tumor burden (69.50%; p<0.01) and increase of life span (73.13%; p<0.001) of EAC-bearing mice at 75mg/kg/day. Besides, SCBME restored the blood toxicity towards normal in EAC-bearing mice (p<0.05).

DISCUSSION

SCBME treated EAC cells showed apoptotic features under a fluorescence microscope and fragmented DNA in DNA laddering assay. Moreover, up-regulation of the tumor suppressor p53 and pro-apoptotic Bax and down-regulation of NF-κB and anti-apoptotic Bcl-2 genes implied induction of apoptosis followed by SCBME treatment.

CONCLUSION

The antiproliferative activity of SCBME against EAC cells is likely due to apoptosis, mediated by regulation of p53 and NF-κB signaling. Thus, SCBME can be considered as a useful resource in cancer chemotherapy.

Enhancement of Cisplatin Cytotoxicity by Cu(II)-Mn(II) Schiff Base Tetradentate Complex in Human Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (SCC) is one of the most predominant tumors worldwide and the present treatment policies are not enough to provide a specific solution. We aimed to assess the cytotoxic effect of Cu(II)–Mn(II) Schiff base tetradentate complex alone or in combination with cisplatin against squamous cell carcinoma cell line (SCCs) in vitro. Oral-derived gingival mesenchymal stem cells (GMSCs) were used as control. The cell viability was assessed by MTT assay. IC50 values were calculated. Evaluation of apoptosis and DNA damage were performed. In addition, the expression of pro-apoptotic and anti-apoptotic genes and proteins were tested. IC50 values indicated less toxicity of the Schiff base complex on GMSCs compared to cisplatin. Schiff base complex treatment resulted in up-regulation of p53 and Bax genes expression and down-regulation of Bcl2 gene expression in SCCs paralleled with increased protein expression of caspase-3 and Bax and down-regulation of Bcl-2 protein. Annexin V-FITC apoptosis kit showed a higher apoptotic effect induced by a Schiff base complex compared to the cisplatin-treated group. These effects were markedly increased on the combination of Schiff base and cisplatin. The present study established that Cu(II)–Mn(II) Schiff base tetradentate complex might induce a cytotoxic effect on SCCs cells via induction of the apoptotic pathway. Moreover, this Schiff base complex augments the anticancer effect of cisplatin.

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

NF-κB is a key signaling pathway molecule linking hepatoma and chronic inflammation. Inhibition of NF-κB activation can alleviate inflammation, and promote hepatoma cell apoptosis. In this study, a series of fluoro-substituted 1,4,5,6,7,8-hexahydropyrido[4,3-d]pyrimidines (PPMs, 31-57) were synthesized from 3,5-bis(arylidene)-4-piperidones (BAPs, 4-30) based on scaffold hopping. We successfully discovered the most potent 43 substituted by electron-withdrawing substitutes (3-F and 4-CF₃) exhibited less toxicity and higher anti-inflammatory activity. Preliminary mechanistic studies revealed that 43 induced dose-dependent cell apoptosis at cell and protein level, while inhibited NF-κB activation by suppressing LPS-induced phosphorylation levels of p65, IκBα and Akt, and by indirectly suppressing MAPK signaling, and by inhibiting the nuclear translocation of NF-κB induced by TNF-α or LPS. Docking analysis verified simulated 43 could reasonably bind to the active site of Bcl-2, p65 and p38 proteins. This compound, as a novel NF-κB inhibitor, also demonstrated both anti-inflammatory and anti-hepatoma activities, warranting its further development as a potential multifunctional agent for the clinical treatment of liver cancers and inflammatory diseases.

Crystal structure and anti-inflammatory activity of (3E,5E)-3,5-bis(4-fluorobenzylidene)-1-((4-fluorophenyl)sulfonyl)piperidin-4-one-dichloromethane (1/1), C26H20Cl2F3NO3S

C26H20Cl2F3NO3S, triclinic, P1̄ (no. 2), a = 8.5616(4) Å, b = 11.6052(6) Å, c = 14.1451(8) Å, α = 66.617(6)°, β = 82.391(4)°, γ = 69.072(4)°, V = 1204.85(12) Å3, Z = 2, R gt(F) = 0.0460, wR ref(F 2) = 0.1206, T = 100.00(10) K.

Crystal structure and anti-inflammatory activity of (3E,5E)-3,5-bis(2-fluorobenzylidene)-1-((4-fluorophenyl)sulfonyl)piperidin-4-one, C25H18F3NO3S

C25H18F3NO3S, orthorhombic, Pca21 (no. 29), a = 19.1142(7) Å, b = 11.6722(5) Å, c = 9.2390(3) Å, V = 2061.26(13) Å3, Z = 4, R gt(F) = 0.0422, wR ref(F 2) = 0.0974, T = 100.02(10) K.

The crystal structure of (E)-N′-(1-(3-chloro-4-fluorophenyl) ethylidene)-2-hydroxybenzohydrazide, C15H12ClFN2O2

C15H12ClFN2O2, monoclinic, P21/c (no. 14), a = 13.9210(13) Å, b = 13.2329(15) Å, c = 18.7191(19) Å, β = 126.250(2)°, V = 2780.9(5) Å3, Z = 8, R gt(F) = 0.0499, wR ref(F 2) = 0.1420, T = 293(2) K.

Crystal structure and anti-inflammatory activity of (3E,5E)-1-((4-chlorophenyl)sulfonyl)-3-(pyridin-4-ylmethylene)-5-(2-(trifluoromethyl)benzylidene)piperidin-4-one, C25H18ClF3N2O3S

C25H18ClF3N2O3S, monoclinic, P21/n (no. 14), a = 9.9087(5) Å, b = 21.7843(10) Å, c = 10.2512(6) Å, β = 94.749(5)°, V = 2205.2(2) Å3, Z = 4, R gt(F) = 0.0448, wR ref(F 2) = 0.1028, T = 100 K.

Crystal structure and anti-inflammatory activity of (3E,5E)-1-((4-bromophenyl)sulfonyl)-3-(pyridin-4-ylmethylene)-5-(2-(trifluoromethyl)benzylidene)piperidin-4-one, C25H18BrF3N2O3S

C25H18BrF3N2O3S, monoclinic, P21/n (no. 14), a = 9.9295(11) Å, b = 21.755(2) Å, c = 10.2358(11) Å, β = 95.022(10)°, V = 2202.6(4) Å3, Z = 4, R gt(F) = 0.0373, wR ref(F 2) = 0.0795, T = 100(1) K.

Crystal structure of (3E,5E)-1-((4-fluorophenyl)sulfonyl)-3,5-bis(3-nitrobenzylidene)piperidin-4-one — dichloromethane (2/1), C51H38Cl2F2N6O14S2

C51H38Cl2F2N6O14S2, triclinic, P1̄ (no. 2), a = 11.8987(6) Å, b = 14.0939(8) Å, c = 16.1915(9) Å, α = 67.590(5)°, β = 75.402(5)°, γ = 77.522(4)°, V = 2407.3(2) Å3, Z = 2, Rgt(F) = 0.0584, wRref(F2) = 0.1645, T = 100.0(1) K.

Crystal structure and anti-inflammatory activity of (3E,5E)-3-(2-fluorobenzylidene)-1-((4-acetamidophenyl)sulfonyl)-5-(pyridin-3-ylmethylene)piperidin-4-one-methanol-hydrate (2/1/1), C53H50F2N6O10S2

C53H50F2N6O10S2, monoclinic, P21/n (no. 14), a = 15.088(5) Å, b = 23.560(9) Å, c = 15.401(6) Å, β = 112.254(5)°, V = 5067(3) Å3, Z = 4, R gt(F) = 0.0509, wR ref(F 2) = 0.1336, T = 298(2) K.

Potential multifunctional agents with anti-hepatoma and anti-inflammation properties by inhibiting NF-кB activation

Inhibition of NF-κB signalling has been demonstrated as a therapeutic option in treating inflammatory diseases and cancers. Herein, we synthesized novel dissymmetric 3,5-bis(arylidene)-4-piperidones (BAPs, 83-102) and characterized fully. MTT and ELISA assay were performed to screen the anti-hepatoma and anti-inflammation properties. 96 showed the most potential bioactivity. 96 could promote HepG2 apoptosis through up-regulating the expression of C-Caspase-3 and Bax, down-regulating the expression of Bcl-2, while markedly inhibit LPS or TNF-α-induced activation of NF-κB through both inhibiting the phosphorylation of IκBα and p65, and preventing the p65 nuclear translocation to exhibit both anti-hepatoma and anti-inflammatory activities. Molecular docking verified that simulated 96 can effectively bond to the active site of Bcl-2 and NF-κB/p65 proteins. 96 inhibited xenografts growth by reducing the expression of TNF-α and Bcl-2 in the tumour tissue. This study suggested that 96 could be developed as a potential multifunctional agent for treatment of inflammatory diseases and cancers.

Synthesis, crystal structures and anti-inflammatory activity of fluorine-substituted 1,4,5,6-tetrahydrobenzo[h]quinazolin-2-amine derivatives

Two fluorine-substituted 1,4,5,6-tetrahydrobenzo[h]quinazolin-2-amine (BQA) derivatives, namely 2-amino-4-(2-fluorophenyl)-9-methoxy-1,4,5,6-tetrahydrobenzo[h]quinazolin-3-ium chloride, (8), and 2-amino-4-(4-fluorophenyl)-9-methoxy-1,4,5,6-tetrahydrobenzo[h]quinazolin-3-ium chloride, (9), both C₁₉H₁₉FN₃O⁺·Cl^-, were generated by Michael addition reactions between guanidine hydrochloride and the α,β-unsaturated ketones (E)-2-(2-fluorobenzylidene)-7-methoxy-3,4-dihydronaphthalen-1(2H)-one, C₁₈H₁₅FO₂, (6), and (E)-2-(4-fluorobenzylidene)-7-methoxy-3,4-dihydronaphthalen-1(2H)-one, (7). Because both sides of α,β-unsaturated ketones (6) or (7) can be attacked by guanidine, we obtained a pair of isomers in (8) and (9). Single-crystal X-ray diffraction indicates that each isomer has a chiral C atom and both (8) and (9) crystallize in the achiral space group P2₁/c. The chloride ion, as a hydrogen-bond acceptor, plays an important role in the formation of multiple hydrogen bonds. Thus, adjacent molecules are connected through intermolecular hydrogen bonds to generate a banded structure. Furthermore, these bands are linked into an interesting 3D network via hydrogen bonds and π-π interactions. Fortunately, the solubilities of (8) and (9) were distinctly improved and can exceed 50 mg ml^-1 in water or PBS buffer system (pH 7.4) at room temperature. In addition, the results of an investigation of anti-inflammatory activity show that (8) and (9), with o- and p-fluoro substituents, respectively, display more potential for inhibitory effects on LPS-induced NO secretion than starting ketones (6) and (7).

Crystal structure of (3E,5E)-3,5-bis(3-nitrobenzylidene)-1-((4-(trifluoromethyl)phenyl)sulfonyl)piperidin-4-one — dichloromethane (2/1), C53H38Cl2F6N6O14S2

C53H38Cl2F6N6O14S2, triclinic, P1̄ (no. 2), a = 12.1975(6) Å, b = 13.9973(7) Å, c = 16.3818(10) Å, α = 69.365(5)°, β = 76.620(5)°, γ = 77.292(4)°, V = 2516.8(3) Å3, Z = 2, R gt(F) = 0.0540, wR ref(F 2) = 0.1413, T = 100.02(10) K.

Crystal structure of (3E,5E)-3,5-bis(4-cyanobenzylidene)-1-((4-fluorophenyl)sulfonyl)piperidin-4-one, C27H18FN3O3S

C27H18FN3O3S, monoclinic, P21/c (no. 14), a = 8.091(6) Å, b = 42.84(3) Å, c = 7.096(6) Å, β = 107.806(10)°, V = 2342(3) Å3, Z = 4, R gt(F) = 0.0616, wR ref(F 2) = 0.1321, T = 173(2) K.

Dissymmetric pyridyl-substituted 3,5-bis(arylidene)-4-piperidones as anti-hepatoma agents by inhibiting NF-κB pathway activation

To get new anti-hepatoma agents with anti-inflammatory activity and hypotoxicity, a series of dissymmetric pyridyl-substituted 3,5-bis(arylidene)-4-piperidones (BAPs, 25-82) were designed and synthesized. Many of them exhibited potential anti-hepatoma properties against human hepatocellular carcinoma cell lines (HepG2, QGY-7703, SMMC-7721) and hypotoxicity for human normal heptical cell line (HHL-5, LO2), and prominently inhibited lipopolysaccharides (LPS) induced IL-6, TNF-α secretion to exert its anti-inflammatory effect. Combining the data of cytotoxicity, cytocompatibility and anti-inflammatory activity, 3-pyridyl and -CF₃ substituted 67 may be the potential anti-hepatoma agent. 67 effectively promoted cell apoptosis through up-regulating cleaved caspase-3 and Bax expression and down-regulating Bcl-2 expression. Furthermore, 67 prominently inhibited NF-κB pathway activation by blocking the phosphorylation of IκBα, p65 and the nuclear translocation of NF-κB induced by TNF-α and LPS. In addition, 67 could reasonably bind to the active site of Bcl-2 and NF-κB/p65 protein proved by Molecular docking analyses. Moreover, 67 significantly suppressed the growth and inflammatory response of HepG2 xenografts in nude mice and was relatively nontoxic to mice. These results suggest that 67 may be effective and hypotoxicity anti-hepatoma agent for the clinical treatment of liver cancers.