Synthesis and anti-inflammatory activity of benzophenone analogues

Synthesis and Phytocytogenotoxic Activity of N-Phenyl-2-phenoxyacetamides Derived from Thymol

The excessive use of herbicides has caused a series of problems related to human health, environmental pollution, and an increase in the resistance of plants to commercial herbicides. As an alternative, natural compounds and their semisynthetic derivatives have been widely studied to obtain environmentally friendly and more effective herbicides than the usual ones. In view of these factors, the aim of this work was to synthesize new molecules with herbicidal potential using thymol as a starting material, a natural phenol that has a pronounced phytotoxic effect. Novel N-phenyl-2-thymoxyacetamides were synthesized and characterized by MS and by 1H and 13C NMR. All prepared molecules were subjected to phytotoxic and cytotoxic activity assays using Lactuca sativa L. and Sorghum bicolor L. as model plants. Molecules containing chlorine in the para position of the thymoxy group exhibited phytotoxic and cytogenotoxic effects superior to those of the commercial herbicides 2,4-D and glyphosate.

Multi-target action of Garcinia livingstonei extract and secondary metabolites against fatty acid synthase, α-glucosidase, and xanthine oxidase

Garcinia livingstonei is a traditional herbal medicine that showed beneficial health effects and bioactivities. Four compounds have been isolated from the plant leaves and were elucidated as lupeol, betulin, podocarpusflavone A, and amentoflavone. The inhibitory activities of G. livingstonei extract and isolated metabolites against fatty acid synthase (FAS), α-glucosidase, and xanthine oxidase (XO) were investigated in vitro. The affinity of the compounds toward the studied enzymes was investigated in silico. The plant extract inhibited FAS, α-glucosidase, and XO with IC50 values of 26.34, 67.88, and 33.05 µg/mL, respectively. Among the isolated metabolites, betulin exhibited the most inhibitory activity against α-glucosidase and XO with IC50 values of 38.96 and 30.94 µg/mL, respectively. Podocarpusflavone A and betulin were the most potent inhibitors of FAS with IC50 values of 24.08 and 27.96 µg/mL, respectively. Computational studies corroborated these results highlighting the interactions between metabolites and the enzymes. In conclusion, G. livingstonei and its constituents possess the potential to modulate enzymes involved in metabolism and oxidative stress.

Structural, Hirshfeld surface and three-dimensional inter-action-energy studies of 1,3,5-triethyl 2-amino-3,5-di-cyano-4,6-bis-(4-fluoro-phen-yl)cyclo-hex-1-ene-1,3,5-tri-carboxyl-ate

In the title compound, C₂₉H₂₇F₂N₃O₆, which crystallizes in the monoclinic space group P2₁/c, the cyclo-hexenone ring is puckered and adopts an envelope conformation. The crystal structure features various inter-molecular inter-actions, such as N-H⋯O, C-H⋯N and C-H⋯O. These inter-actions were investigated using Hirshfeld surface analysis and the three-dimensional inter-action energies were calculated using the B3LYP/6-31 G(d,p) energy density model.

Effects of Ethanolic and Aqueous Extracts of Garcinia gardneriana Leaves in an In Vivo Experimental Model Induced by a Hyperlipidic Diet

The study of medicinal plants, such as the genus Garcinia (Clusiaceae), in the treatment of non-communicable chronic diseases has aroused the interest of researchers. However, there are no studies in the literature that have investigated the effects of Garcinia gardneriana in experimental models of obesity for possible metabolic alterations. Swiss mice receiving a high-fat diet were supplemented with aqueous or ethanolic extract of G. gardneriana at doses of 200 or 400 mg/kg/day. It was found that there was a reduction in food consumption in experimental groups compared with the control groups, and the group supplemented with aqueous extract at a dose of 200 mg/kg/daydisplayed a reduction in weight. The results showed an increase in the values of high density lipoprotein (HDL-c), total cholesterol, triglycerides and fasting blood glucose. G. gardneriana did not protect against insulin resistance, and caused in an increase in monocyte chemoattractant protein-1 (MCP-1) concentrations and a reduction in interleukin 10 (IL-10). In addition, hepatic steatosis and microvesicular steatosis were indicated. It was revealed that, under the experimental conditions in the study, G. gardneriana did not prevent weight gain or comorbidities; that is, a different behavior was obtained from that described in the literature with regard to the medicinal potential of the Garcinia species, which is probably related to the phytochemical properties.

Polyisoprenylated benzophenones and xanthones from the pericarp of Garcinia planchonii Pierre

Two new polyisoprenylated benzophenones, planchoniones A (1) and B (2), together with two known benzophenones (3, 4) and six known xanthones (5-10), were isolated from an ethyl acetate extract of the pericarp of Garcinia planchonii Pierre. Their structures were established using spectroscopic methods, mainly 1D and 2D NMR. The four benzophenones were evaluated for their cytotoxicity against MCF-7 human breast cancer cells, and showed almost no activity. Meanwhile, compounds 5-10 were investigated for their inhibitory effects towards α-glucosidase, and γ-mangostin (5) exhibited the most remarkable effect with IC₅₀ value of 15.3 ± 0.9 µM (compared with acarbose, IC₅₀ = 224.9 ± 3.6 µM).

Synthesis, Characterization, Hirshfeld Surface Analysis, Crystal Structure and Molecular Modeling Studies of 1-(4-(Methoxy(phenyl)methyl)-2-methylphenoxy)butan-2-one Derivative as a Novel α-Glucosidase Inhibitor

The crystal compound was synthesized and characterized using conventional analytical techniques. The compound C19H21O3 crystallizes in a monoclinic crystal system with the space group P21/c. The crystal structure is stabilized by C-H…O interactions. The structure is further reinforced by π-π interactions. During in vitro inhibition of α-glucosidase, the crystal compound exhibited a significant inhibition of the enzyme (IC50: 10.30 ± 0.25 µg/mL) in comparison with the control, acarbose (IC50: 12.00 ± 0.10 µg/mL). Molecular docking studies were carried out for the crystal compound with the α-glucosidase protein model, which demonstrated that the crystal molecule has a good binding affinity (−10.8 kcal/mol) compared with that of acarbose (−8.2 kcal/mol). The molecular dynamics simulations and binding free energy calculations depicted the stability of the crystal molecule throughout the simulation period (100 ns). Further, a Hirshfeld analysis was carried out in order to understand the packing pattern and intermolecular interactions. The energy difference between the frontier molecular orbitals (FMO) was 4.95 eV.

Molecular docking prediction and in vitro studies elucidate anti-inflammatory effect of Garcinia extract against inducible nitric oxide synthase and cyclooxygenase-2 targets

Background

Garcinia is a tropical plant that has been traditionally used in medicinal folklore for its potential antioxidant, antibacterial, anti-hyperlipidemic, anti-diabetic, hepatoprotective, etc. In this study, methanolic extract of Garcinia herbal supplement (GME) and its important phytoconstituents (Garcinol and hydroxycitric acid) were evaluated for their inhibitory action against important inflammatory markers iNOS and COX-2 in lipopolysaccharide-induced RAW 264.7 cells. iNOS and COX-2 play a major role in the process of inflammation, and inhibition of these molecules will help to alleviate the inflammatory process. The cells were pre-treated with two doses of GME (115 µg/ml and 230 µg/ml); Ggarcinol (6 µM and 12 µM); hydroxycitric acid (17.5 µg/ml and 35 µg/ml) followed by stimulation with 1 µg/ml of LPS for 24 h.

Results

The results of the study demonstrated that Garcinia and its active components Garcinol and HCA play an important role in suppressing LPS-induced relative mRNA expression of iNOS, COX-2, and subsequent reduction in the levels of total nitric oxide and prostaglandinE2. Molecular docking analysis of Ggarcinol and HCA with iNOS and COX-2 proteins showed potent interactions with negative binding energies.

Conclusions

This study suggests that Garcinia possess anti-inflammatory activity thus providing a possibility for drug designing as iNOS and COX-2 inhibitor.

Graphical Abstract

Angiogenesis as a potential treatment strategy for rheumatoid arthritis

Angiogenesis is an early and key event in the pathogenesis of rheumatoid arthritis (RA) and is crucial for the proliferation of synovial tissue and the formation of pannus. This process is regulated by both angiogenesis-stimulating factors and angiogenesis inhibitors, the basis for the "on-off hypothesis of angiogenesis." In RA, inflammation, immune imbalance, and hypoxia can further turn on the switch for blood vessel formation and induce angiogenesis. The new vasculature can recruit white blood cells, induce immune imbalance, and aggravate inflammation. At the same time, it also can provide oxygen and nutrients for the proliferating synovial tissue, which can accelerate the process of RA. The current therapies for RA mainly target the inflammatory response of autoimmune activation. Although these therapies have been greatly improved, there are still many patients whose RA is difficult to treat or who do not fully respond to treatment. Therefore, new innovative therapies are still urgently needed. This review covers the mechanism of synovial angiogenesis in RA, including the detailed process of angiogenesis and the relationship between inflammation, immune imbalance, hypoxia, and synovial angiogenesis, respectively. At the same time, in the context of the development of angiogenesis inhibition therapy for cancer, we also discuss similar treatment strategies for RA, especially the combination of targeted angiogenesis inhibition therapy and immunotherapy.

Medicinal Potential of Garcinia Species and Their Compounds

Garcinia is a genus of Clusiaceae, distributed throughout tropical Asia, Africa, New Caledonia, Polynesia, and Brazil. Garcinia plants contain a broad range of biologically active metabolites which, in the last few decades, have received considerable attention due to the chemical compositions of their extracts, with compounds which have been shown to have beneficial effects in several diseases. Our work had the objective of reviewing the benefits of five Garcinia species (G. brasiliensis, G. gardneriana, G. pedunculata, G. cambogia, and G. mangstana). These species provide a rich natural source of bioactive compounds with relevant therapeutic properties and anti-inflammatory effects, such as for the treatment of skin disorders, wounds, pain, and infections, having demonstrated antinociceptive, antioxidant, antitumoral, antifungal, anticancer, antihistaminic, antiulcerogenic, antimicrobial, antiviral, vasodilator, hypolipidemic, hepatoprotective, nephroprotective, and cardioprotective properties. This demonstrates the relevance of the genus as a rich source of compounds with valuable therapeutic properties, with potential use in the prevention and treatment of nontransmissible chronic diseases.

Design, synthesis and molecular docking of benzophenone conjugated with oxadiazole sulphur bridge pyrazole pharmacophores as anti inflammatory and analgesic agents

The prostaglandins (PG) a group of physiologically active lipid compounds having diverse hormone like effects are important mediators of the body's response to pain and inflammation, and are formed from essential fatty acids found in cell membranes. This reaction is catalyzed by cyclooxygenase, a membrane associated enzyme occurring in two isoforms, COX-1 and COX-2. Nonsteroidal anti-inflammatory drugs (NSAIDs) act by inhibiting the activity of COX. In view of this, a series of novel benzophenones conjugated with oxadiazole sulphur bridge pyrazole moiety 8a-l were designed, synthesized, characterized and subsequently evaluated for anti-inflammatory and analgesic property. The investigation of novel analogues 8a-l for potential anti-inflammatory activity showed high levels of COX-1 and COX-2 inhibitory activity. Among the series, compound 8i with electron withdrawing fluoro group at the para position of the benzoyl ring of benzophenone was characterized by highest IC₅₀ values for both COX-1 and COX-2 inhibition, which is comparable to the standard drug. Further, molecular docking studies have been performed for the potent compound.

Benzophenone: a ubiquitous scaffold in medicinal chemistry

The benzophenone scaffold represents a ubiquitous structure in medicinal chemistry because it is found in several naturally occurring molecules which exhibit a variety of biological activities, such as anticancer, anti-inflammatory, antimicrobial, and antiviral. In addition, various synthetic benzophenone motifs are present in marketed drugs. They also represent important ingredients in perfumes and can act as photoinitiators. This review will provide an overview of benzophenone moieties with medicinal aspects synthesized in the last 15 years and will cover the most potent molecule in each report. In this review, only benzophenones with substitutions on their aryl rings, i.e. diphenyl ketone analogues, have been covered.

Targeting synovial neoangiogenesis in rheumatoid arthritis

In Rheumatoid arthritis (RA), neoangiogenesis is an early and crucial event to promote the development of the hyperplasic proliferative pathologic synovium. Endothelial cells are critical for the formation of new blood vessels since they highly contribute to angiogenesis and vasculogenesis. Current therapies in RA target the inflammatory consequences of autoimmune activation and despite major improvements these last years still refractory patients or incomplete responders may be seen raising the point of the need to identify complementary additive and innovative therapies. This review resumes the mechanisms of synovial neoangiogenesis in RA, including recent insights on the implication of vasculogenesis, and the regulation of synovial neoangiogenesis by angiogenic and inflammatory mediators. In line with the recent development of vascular-targeted therapies used in cancer and beyond, we also discuss possible therapeutic implications in RA, in particular the combination of targeted immunotherapies with anti-angiogenic molecules.

Ethyl 2-(4-chloro-3-methylphenoxy)acetate

In the title compound, C11H13ClO3, the pendant ethyl chain has an extended conformation and lies in the plane of the substituted benzene ring; the r.m.s. deviation of the 15 non-H atoms comprising the molecule is 0.002 Å. The crystal structure features inversion-related dimers linked by pairs of benzene–carbonyl C—H...O hydrogen bonds, generatingR22(16) loops.

2-Chloro-6-fluorophenyl 4-chlorobenzoate

In the title compound, C13H7Cl2FO2, the dihedral angle between the aromatic rings is 49.96 (12)° and the fluorine atom issynto the C=O group. In the crystal, the molecules are linked into [010] chains by C—H...O hydrogen bonds and weak C—H...Cl interactions link these chains into sheets parallel to the (101) plane.

Design and synthesis of diamide-coupled benzophenones as potential anticancer agents

A series of diamide-coupled benzophenone, 2-(4-benzoyl-phenoxy)-N-{2-[2-(4-benzoyl-phenoxy)-acetylamino]-phenyl}-acetamide analogues (9a-l) were synthesized by multistep reactions and all compounds were well characterized. Among the series (9a-l), compound 9k with three methyl groups at ortho position in rings A, B, and D and bromo group at the para position in ring E was selected as a lead compound by screening through multiple cancer cell types by in-vitro cytotoxic and antiproliferative assay systems. Also, the cytotoxic nature of the compound 9k resulted the regression of the tumor growth in-vivo, which could be due to decreased vascularisation in the peritoneum lining of the mice which regress the tumor growth. The results were reconfirmed in-vivo chorioallantoic membrane model which indicates a scope of developing 9k into potent anticancer drug in near future.

Resolving the Benzophenone DNA-Photosensitization Mechanism at QM/MM Level

Benzophenone, the parent of the diarylketone family, is a versatile compound commonly used as a UV blocker. It may also trigger triplet-based DNA photosensitization. Therefore, benzophenone is involved in DNA photodamage induction. In the absence of experimentally resolved structure, the mechanism of DNA damage production remains elusive. Employing a hybrid quantum mechanics/molecular mechanics approach, here we address the spin transfer mechanism between this drug and proximal thymine, that is, the DNA nucleobase most prone to suffer triplet damages.

Synthesis, angiopreventive activity, and in vivo tumor inhibition of novel benzophenone-benzimidazole analogs

AIM

The development of anticancer drugs with specific targets is of prime importance in modern biology. This study investigates the angiopreventive and in vivo tumor inhibition activities of novel synthetic benzophenone-benzimidazole analogs.

MAIN METHODS

The multistep synthesis of novel benzophenone-benzimidazole analogs (8a-n) allowing substitution with methoxy, methyl and halogen groups at different positions on the identical chemical backbone and the variations in the number of substituents were synthesized and characterized. The newly synthesized compounds were further evaluated for cytotoxic and antiproliferative effects against Ehrlich ascites carcinoma (EAC) cells. The potent lead compounds were further assessed for antiangiogenic effects in a CAM model and a tumor-induced vasculature in vivo model. The effect of angioprevention on tumor growth was verified in a mouse model.

KEY FINDINGS

The cytotoxicity studies revealed that compounds 8f and 8n are strongly cytotoxic. Analyzing the structure-activity relationship, we found that an increase in the number of methyl groups in addition to methoxy substitution at the para position of the benzoyl ring in compound 8n resulted in higher potency compared to 8f. Furthermore, neovessel formation in in vivo systems, such as the chorioallantoic membrane (CAM) and tumor-induced mice peritoneum models, was significantly suppressed and reflected the tumor inhibition observed in mice.

SIGNIFICANCE

These results suggest the potential clinical application of compound 8n as an antiangiogenic drug for cancer therapy.

2-Benzoyl-4-chloro-phenyl benzoate

In the title compound, C20H13ClO3, the dihedral angles between the benzoate and the chloro-benzene and benzoyl rings are 68.82 (5) and 53.76 (6)°, respectively, while the dihedral angle between the benzoyl and benzoate rings is 81.17 (5)°. The eight atoms of the benzoyl residue are essentially planar with the exception of the O atom which lies 0.1860 (5) Å out of their mean plane (r.m.s. deviation = 0.97 Å). The nine atoms of benzoate residue are also essentially planar (r.m.s. deviation = 0.20 Å) with the ester O atom showing the greatest deviation [0.407 (12) Å] from their mean plane. In the crystal, mol-ecules are connected into centrosymmetric dimers by pairs of C-H⋯O hydrogen bonds.

4-hydroxy-2,5-dimethylphenyl-benzophenone: conformational stability, FT-IR and Raman investigation

In this paper we have studied the 4-hydroxyl-2,5 dimethylphenyl-benzophenone. Also, it was analyzed the vibrational assignment (FT-IR and Raman) in conjunction with computational results. The conformational analysis showed three barrier heights where two are due to the dihedral rotation and the other one is attributed to hydroxyl rotation. While the high dihedral rotational barrier (TS1) is 6.06-7.22 kcal mol(-1), the lower one (TS2) is almost three times smaller. The variations with the change of basis set is 5-8% to TS1, and 3-15% in the values predicted to TS2. In the case of OH rotational barrier, the values range from 3.70 to 4.86 kcal mol(-1), and it is also observed that this transition state is less sensitive to the change of basis set and to the method. Two isomers was detected due to the changes in the OH rotation with the gap energy lower than 0.7 kcal mol(-1), and at this point is seen that semi-empirical methods fail into describe the most stable conformation which may be due to the small energy gap. The enthalpy formation at 0 K and 298 K was 111.71 and 102.20 kcal mol(-1), respectively.

UV filters, ingredients with a recognized anti-inflammatory effect

BACKGROUND

To explain observed differences during SPF determination using either an in vivo or in vitro method, we hypothesized on the presence of ingredients having anti-inflammatory properties.

METHODOLOGY/PRINCIPAL FINDINGS

To research our hypothesis, we studied the 21 UV filters both available on the market and authorized by European regulations and subjected these filters to the phorbol-myristate-acetate test using mice. We then catalogued the 13 filters demonstrating a significant anti-inflammatory effect with edema inhibition percentages of more than 70%. The filters are: diethylhexyl butamido triazone (92%), benzophenone-5 and titanium dioxide (90%), benzophenone-3 (83%), octocrylène and isoamyl p-methoxycinnamate (82%), PEG-25 PABA and homosalate (80%), octyl triazone and phenylbenzimidazole sulfonic acid (78%), octyl dimethyl PABA (75%), bis-ethylhexyloxyphenol methoxyphenyl triazine and diethylamino hydroxybenzoyl hexylbenzoate (70%). These filters were tested at various concentrations, including their maximum authorized dose. We detected a dose-response relationship.

CONCLUSIONS/SIGNIFICANCE

The anti-inflammatory effect of a sunscreen ingredient may affect the in vivo SPF value.

Inhibition of HIF-1alpha activity by BP-1 ameliorates adjuvant induced arthritis in rats

Rheumatoid arthritis (RA) is a chronic inflammatory, angiogenic disease. Inflamed synovitis is a hallmark of RA which is hypoxic in nature. Vascular endothelial growth factor (VEGF), one of the key regulators of angiogenesis, is overexpressed in the pathogenesis of RA. VEGF expression is regulated by hypoxia-inducible factor-1alpha (HIF-1alpha), a master regulator of homeostasis which plays a pivotal role in hypoxia-induced angiogenesis. In this study we show that synthetic benzophenone analogue, 2-benzoyl-phenoxy acetamide (BP-1) can act as a novel anti-arthritic agent in an experimental adjuvant induced arthritis (AIA) rat model by targeting VEGF and HIF-1alpha. BP-1 administered hypoxic endothelial cells and arthritic animals clearly showed down regulation of VEGF expression. Further, BP-1 inhibits nuclear translocation of HIF-1alpha, which in turn suppresses transcription of the VEGF gene. These results suggest a further possible clinical application of the BP-1 derivative as an anti-arthritic agent in association with conventional chemotherapeutic agents.

Synthesis and crystallographic analysis of benzophenone derivatives—The potential anti-inflammatory agents

Fries rearrangement of substituted phenyl benzoates 1a-j to substituted hydroxy benzophenones 2a-j was achieved in excellent yield. Further benzoylation of 2a-j to benzoyloxy benzophenones 4a-n, a benzophenone analogue was achieved in good yield. All the newly synthesized compounds were evaluated for their anti-inflammatory activity and were compared with standard drugs. Out of the compounds studied, the compounds 4c, 4e, 4g, 4h and 4k with chloro and methyl substituents at para position showed more potent activity than the standard drugs at all doses tested.

2,2′,4-Trihydroxybenzophenone: Crystal Structure, and Anti-Inflammatory and Antioxidant Activities

The crystal structure of '2,2',4-trihydroxybenzophenone' (=(2,4-dihydroxyphenyl)(2-hydroxyphenyl)methanone; 1) was determined, and its molecular structure, along with intra- and intermolecular H-bonds, was analyzed. The anti-inflammatory potential of 1, evaluated by means of the rat-paw-edema assay, with carrageenan as inflammation stimulus, was found to be similar high as that of indomethacin. In contrast, benzophenone proper (2) was hardly active in this assay. Our results indicate that these anti-inflammatory effects are related to the action of kinins and prostaglandins. The radical-scavenging properties of 1 towards DPPH were found to be similar as those of typical phenolics, but somewhat lower than that of ascorbic acid. The structure-activity relationship (SAR) of 1 is discussed.

Aspergillus fumigatus CY018, an endophytic fungus in Cynodon dactylon as a versatile producer of new and bioactive metabolites

Aspergillus fumigatus CY018 was recognized as an endophytic fungus for the first time in the leaf of Cynodon dactylon. By bioassay-guided fractionation, the EtOAc extract of a solid-matrix steady culture of this fungus afforded two new metabolites, named asperfumoid (1) and asperfumin (2), together with six known bioactive compounds including monomethylsulochrin, fumigaclavine C, fumitremorgin C, physcion, helvolic acid and 5alpha,8alpha-epidioxy-ergosta-6,22-diene-3beta-ol as well as other four known compounds ergosta-4,22-diene-3beta-ol, ergosterol, cyclo(Ala-Leu) and cyclo(Ala-Ile). Through detailed spectroscopic analyses including HRESI-MS, homo- and hetero-nuclear correlation NMR experiments (HMQC, COSY, NOESY and HMBC), the structures of asperfumoid and asperfumin were established to be spiro-(3-hydroxyl-2,6-dimethoxyl-2,5-diene-4-cyclohexone-(1,3')-5'-methoxyl-7'-methyl-(1'H, 2'H, 4'H)-quinoline-2',4'-dione) and 5-hydroxyl-2-(6-hydroxyl-2-methoxyl-4-methylbenzoyl)-3,6-dimethoxyl-benzoic methyl ester, respectively. All of the 12 isolates were subjected to in vitro bioactive assays against three human pathogenic fungi Candida albicans, Tricophyton rubrum and Aspergillus niger. As a result, asperfumoid, fumigaclavine C, fumitremorgin C, physcion and helvolic acid were shown to inhibit C. albicans with MICs of 75.0, 31.5, 62.5, 125.0 and 31.5 microg/mL, respectively.

Synthesis of some newer analogues of substituted dibenzoyl phenol as potent anti-inflammatory agents

Benzoylation of hydroxybenzophenones 1a-f affords substituted benzoyl phenyl benzoates 3a-f, which on Fries rearrangement using microwave irradiation led to a facile synthesis of solely dibenzoyl phenols 4a-f in excellent yield. The newly synthesized compounds were screened for their anti-inflammatory activity and were compared with standard drugs. Out of the compounds studied, the compound 4e showed more potent activity than the standard drugs at all doses tested.