Compounds Showed IC50 Values Research Articles

Design, synthesis, and molecular docking studies of 2-(furan-2-yl)quinazolin-4-one derivatives as potential antiproliferative agents.

Fifteen new derivatives of quinazolin-4-one bearing the 2-furyl moiety at position 2 and a substituted phenyl moiety at position 3 were designed and synthesized to be evaluated as cytotoxic agents. Their chemical structures were confirmed by spectral and elemental analysis; cytotoxic activity evaluation was performed against HEPG2, HCT116, and MCF7 cancer cell lines using the sulforhodamine-B assay. All the tested compounds except 6a showed high potency against the HEPG2 cancer cell line (IC50 8-101 nM/mL); 11 compounds out of 15 proved to be potent against HCT116 cells (IC50 3-49 nM/mL), also 11 of the tested compounds showed high potency against MCF7 cells with IC50 values ranging from 7 to 63 nM/mL. The rest of the tested compounds showed IC50 values of more than 100 nM/mL. Compounds 3e and 4d are the most active compounds against HEPG2 cells; in addition, 3e is the most active compound against MCF7 cells. Also, compounds 4a, 3a, and 3b are the most active compounds against HCT116 cells. Compounds 3a, 3b, 3e, 4a, and 4d were also evaluated for their inhibitory activity against the EGFR tyrosine kinase (EGFR-TK) and showed a percentage inhibitory activity ranging from 53 to 84%. The most potent EGFR-TK inhibitors, 3a (84%), 3b (75%), and 3e (60%), were docked into the ATP binding site of the EGFR to explore their binding mode and possible interactions.

Design, synthesis and biological evaluation of bivalent benzoxazolone and benzothiazolone ligands as potential anti-inflammatory/analgesic agents

Benzoxazolone and benzothiazolone were used as template blocks to develop two series of dimers as anti-inflammatory and analgesic agents based on the concept of bivalent ligands. The first series (I) involved varying the carbon chain lengths extending from the piperazine core to the nitrogen atom of the dibenzo[d]oxazol-2(3H)-one or dibenzo[d]thiazol-2(3H)-one. The second series (II) was designed by changing the attachment point. All compounds were screened for their in vitro anti-inflammatory activity in terms of the inhibition of inducible nitric oxide synthase (iNOS) and nuclear factor kappa B (NF-κB). Seventeen compounds inhibited both targets. Eleven of them exhibited IC50 values below 3μM while five compounds showed IC50 values of 1μM or below. Most of the compounds were found to be devoid of cytotoxicity against mammalian kidney and solid tumors cell lines up to 25μg/mL. In vivo anti-inflammatory and antinociceptive studies revealed that compounds 3j, 5t and 8b have significant anti-inflammatory and analgesic activity comparable to that of indomethacin and ketorolac, respectively.

Bond-based bilinear indices for computational discovery of novel trypanosomicidal drug-like compounds through virtual screening

Two-dimensional bond-based bilinear indices and linear discriminant analysis are used in this report to perform a quantitative structure–activity relationship study to identify new trypanosomicidal compounds. A data set of 440 organic chemicals, 143 with antitrypanosomal activity and 297 having other clinical uses, is used to develop the theoretical models. Two discriminant models, computed using bond-based bilinear indices, are developed and both show accuracies higher than 86% for training and test sets. The stochastic model correctly indentifies nine out of eleven compounds of a set of organic chemicals obtained from our synthetic collaborators. The in vitro antitrypanosomal activity of this set against epimastigote forms of Trypanosoma cruzi is assayed. Both models show a good agreement between theoretical predictions and experimental results. Three compounds showed IC50 values for epimastigote elimination (AE) lower than 50 μM, while for the benznidazole the IC50 = 54.7 μM which was used as reference compound. The value of IC50 for cytotoxicity of these compounds is at least 5 times greater than their value of IC50 for AE. Finally, we can say that, the present algorithm constitutes a step forward in the search for efficient ways of discovering new antitrypanosomal compounds.

Synthesis and biological evaluation of 4-nitroindole derivatives as 5-HT2A receptor antagonists

A novel series of 4-nitroindole sulfonamides containing a methyleneamino-N,N-dimethylformamidine were prepared. The binding of these compounds to 5-HT2A and 5-HT2C was evaluated, and most of the compounds showed IC50 values of less than 1μM, and exhibited high selectivity for the 5-HT2C receptor. However, little selectivity was observed in the functional assay for 5-HT6 receptors. The computational modeling studies further validated the biological results and also demonstrated a reasonable correlation between the activity of compounds and the mode of superimposition with specified pharmacophoric features.

In Silico Inhibitory Activity against Caspase 3 by Zinc (II) Coordinated Complexes

Aims: The presented research paper is aimed to prevalence of apoptosis for the first time by using in silico molecular docking and simulation using caspase-3 zymogen and zinc-coordinated compounds. Antioxidant activities of the coordinated complexes were compared to the positive controls (BHT and ascorbic acid). Study design: Molecular docking analysis was performed by using Autodock 4.2, setting at 150x140x110 Gridbox, center at -57.616, 31.092, 88.666 with 0.375 A spacing. Their antioxidant activity was tested by FRAP and DPPH assay. Place and Duration of Study: Department of Chemistry and department of molecular medicine, Faculty of Medicine, University of Malaya laboratories between January 2014 – July 2014 Methodology: Compounds derived from zinc(II) ion give rise to coordination complexes exhibited CHN, NMR (H & C) and FT-IR spectra consistent with the proposed structures. Based on the xShort Research Article Gwaram and Hassandarvish; IJBcRR, 5(1): 27-38, 2015; Article no. IJBcRR.2015.004 28 ray crystal structure, one of the derivatives is a mononuclear square-pyramidal metal complex, with τ value of 0.35. The molecular docking simulation formed between compounds and caspase 3 showed the ligands bind to the active-site gorge well positioned in the active-site gorge. Results: The residues that have been involved in this protein-ligand interaction docked well by using Autodock 4.2, setting at 150x140x110 Gridbox, center at -57.616, 31.092, 88.666 with 0.375 A spacing in the hydrophobic pocket. Their antioxidant activity tested revealed their FRAP assay values of 531.11±0.021 and 1886.11±0.008 higher than value of 187.3±2.6 shown by BHT used as standard. The compounds showed IC50 values 21.50±0.009 and 14.80±0.002 lower than ascorbic acid with an IC50 value of 2.26±0.001 μg/mL. Conclusion: Synthesized zinc(II) complexes have been confirmed to inhibit the activity of caspase 3 both in silico and in vitro and were tested for antioxidant activity by both FRAP and DPPH methods.

The Useful Medicinal Properties of the Root-Bark Extract of Alstonia boonei (Apocynaceae) May Be Connected to Antioxidant Activity

Folkloric use of root-bark extract of Alstonia boonei in the treatment and management of many disease conditions may be associated with free radical scavenging as part of its mechanisms of action. We therefore evaluated the ability of different solvent fractions of the methanol extract, crude precipitate from the extract, and isolated compound from the crude precipitate for scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Phytochemical analysis revealed the presence of useful phytocompounds. Ethyl acetate fraction showed better antioxidant activity with IC50 of 54.25 μg/mL while acetone and methanol fractions have 121.79 and 141.67 μg/mL, respectively. The crude precipitate and isolated compound showed IC50 values of 364.39 and 354.94 μg/mL, respectively. The crude precipitate, fractions, and compound 1 showed antioxidant activity against DPPH radical although lower than that of ascorbic acid.

(S)-1-(Pent-4′-enoyl)-4-(hydroxymethyl)-azetidin-2-one derivatives as inhibitors of human fatty acid amide hydrolase (hFAAH): synthesis, biological evaluation and molecular modelling

A series of lipophilic ester derivatives (2a–g) of (S)-1-(pent-4′-enoyl)-4-(hydroxymethyl)-azetidin-2-one has been synthesised in three steps from (S)-4-(benzyloxycarbonyl)-azetidin-2-one and evaluated as novel, reversible, β-lactamic inhibitors of endocannabinoid-degrading enzymes (human fatty acid amide hydrolase (hFAAH) and monoacylglycerol lipase (hMAGL)). The compounds showed IC50 values in the micromolar range and selectivity for hFAAH versus hMAGL. The unexpected 1000-fold decrease in activity of 2a comparatively to the known regioisomeric structure 1a (i.e. lipophilic chains placed on N1 and C3 positions of the β-lactam core) could be explained on the basis of docking studies into a revisited model of hFAAH active site, considering one or two water molecules in interaction with the catalytic triad.

Design, synthesis and preliminary evaluation of a series of histone deacetylase inhibitors carrying a benzodiazepine ring

A series of new histone deacetylase inhibitors were designed and synthesized based on hybridization between SAHA or oxamflatin and 5-phenyl-1,4-benzodiazepines. The compounds were tested for their enzyme inhibitory activity on HeLa nuclear extracts, and on human recombinant HDAC1 and HDAC6. Antiproliferative activity was tested on different cancer cells types, while proapoptotic activity was primarily tested on NB4 cells. The compounds showed IC50 values similar to those of SAHA. Compound (S)-8 displayed interesting activity against hematological and solid malignancies.

Novel 5-substituted 1H-tetrazoles as cyclooxygenase-2 (COX-2) inhibitors

A series of novel 5-substituted 1H-tetrazoles as cyclooxygenase-2 (COX-2) inhibitors was prepared via treatment of various diaryl amides with tetrachlorosilane/sodium azide. All compounds were tested in cyclooxygenase (COX) assays in vitro to determine COX-1 and COX-2 inhibitory potency and selectivity. Tetrazoles contained a methylsulfonyl or sulfonamide group as COX-2 pharmacophore displayed only low inhibitory potency towards COX-2. Most potent compounds showed IC50 values of 6 and 7μM for COX-2. All compounds showed IC50 values greater 100μM for COX-1 inhibition.

Design, synthesis and biological evaluation of peptidyl-vinylaminophosphonates as novel cysteine protease inhibitors

We report herein, design and synthesis of vinylaminophosphonates, a novel class of compounds as possible cysteine protease inhibitors. The synthesis of vinylaminophosphonates has been accomplished employing Tsuji–Trost reaction as a key step. The synthesized compounds were assayed against papain, a model cysteine protease and some of our synthesized compounds showed IC50 values in the range of 30–54μM thereby suggesting that these chemical entities thus could constitute an interesting template for the design of potential novel protease inhibitors.

Synthesis and biological evaluation of (phenylpiperazinyl-propyl)arylsulfonamides as selective 5-HT2A receptor antagonists

A novel series of 5-HT2A ligands that contain a (phenylpiperazinyl-propyl)arylsulfonamides skeleton was synthesized. Thirty-seven N-(cycloalkylmethyl)-4-methoxy-N-(3-(4-arylpiperazin-1-yl)propyl)-arylsulfonamide and N-(4-(4-arylpiperazin-1-yl)butan-2-yl)-arylsulfonamide compounds were obtained. The binding of these compounds to the 5-HT2A, 5-HT2C, and 5-HT7 receptors was evaluated. Most of the compounds showed IC50 values of less than 100nM and exhibited high selectivity for the 5-HT2A receptor. Among the synthesized compounds, 16a and 16d showed good affinity at 5-HT2A (IC50=0.7nM and 0.5nM) and good selectivity over 5-HT2C (50–100 times) and 5-HT7 (1500–3000 times).

Synthesis, Biological Evaluation, and Modeling of Dimeric PPI Analogues as Novel DNA Minor Groove Binders

A series of symmetrical dimeric proton pump inhibitor (PPI) analogues, designed as novel type DNA minor groove binders, was synthesized and evaluated for anti-tumor activity. Some of these new compounds showed IC50 values below 10 μM in an in vitro anti-tumor test. A molecular modeling study was performed to confirm the sequence selectivity of these compounds towards AT base pairs in DNA. Two effective compounds were selected and docked into the minor groove of DNA. The snug binding may be responsible for their cytotoxic and anti-tumor effects.

Novel Pyrazolopyrimidopyridazinones with Potent and Selective Phosphodiesterase 5 (PDE5) Inhibitory Activity as Potential Agents for Treatment of Erectile Dysfunction

Pyrazolo[1',5':1,6]pyrimido[4,5-d]pyridazin-4(3H)-ones and their analogues, potentially useful for the treatment of erectile dysfunction, were synthesized and evaluated as inhibitors of phosphodiesterase 5 (PDE5). Several compounds showed IC50 values in the low nanomolar range, and in particular, compound 5r, displaying high potency toward PDE5 (IC50 = 8.3 nM) and high selectivity versus PDE6 (240-fold) appeared to be a very promising new lead both in comparison with the potent but not selective sildenafil and in comparison with some analogues previously reported by us. SAR studies in this triheterocyclic scaffold led us to conclude that the best arranged groups are a methyl in position 1, a benzyl in position 3, a phenyl in position 9, and a linear four-carbon chain in position 6.

Virtual screening for inhibitors of human aldose reductase.

The inhibition of aldose reductase (AR) provides an interesting strategy to prevent the complications of chronic diabetes. Although a large number of different AR inhibitors are known, very few of these compounds exhibit sufficient efficacy in clinical trials. We performed a virtual screening based on the ultrahigh resolution crystal structure of the inhibitor IDD594 in complex with human AR. AR operates on a large scale of structurally different substrates. To achieve this pronounced promiscuity, the enzyme can adapt rather flexibly to its substrates. Likewise, it has a similar adaptability for the binding of inhibitors. We applied a protocol of consecutive hierarchical filters to search the Available Chemicals Directory. In the first selection step, putative ligands were chosen that exhibit functional groups to anchor the anion-binding pocket of AR. Subsequently, a pharmacophore model based on the binding geometry of IDD594 and the mapping of the binding pocket in terms of putative "hot spots" of binding was applied as a second consecutive filter. In a third and final filtering step, the remaining candidate molecules were flexibly docked into the binding pocket of IDD594 with FlexX and ranked according to their estimated DrugScore values. Out of 206 compounds selected by this search and complemented by a cluster analysis and visual inspection, 9 compounds were selected and subjected to biological testing. Of these, 6 compounds showed IC50 values in the micromolar range. According to the proposed binding mode, the two inhibitors BTB02809 (IC50 = 2.4 +/- 0.5 microM) and JFD00882 (IC50 = 4.1 +/- 1.0 microM) both place a nitro group into the hydrophobic specificity pocket of human AR in an orientation coinciding with the position of the bromine atom of IDD594. The interaction of this Br with Thr113 has been identified as a key feature that is responsible for selectivity enhancement.

Design and synthesis of sulfur based inhibitors of matrix metalloproteinase-1.

Fibroblast collagenase (MMP-1), a member of the matrix metalloproteinases family, is believed to be a pathogenesis of arthritis, by cleaving triple-helical type II collagen in cartilage. From the similarity of the active site zinc binding mode with hydroxamate, we designed and synthesized alpha-mercaptocarbonyl possessing compounds (3-5), which incorporated various peptide sequences as enzyme recognition sites. The P4-P1 peptide incorporating compound (3) exhibited as potent inhibition as the hydroxamate (1) and the carboxylate (2) type inhibitors, with an IC50 of 10(-6) M order against MMP-1. But the inhibitor (3) related compounds (6-8) displayed decreased or no inhibitory potencies. These results suggest that the existence of both the carbonyl and thiol groups might be critical for the inhibition, and the distance between the two functional groups is important for inhibitory potency. For Pn' peptide incorporating compounds (4a-k), except for 4h and 4k, all compounds showed IC50 values under sub-nanomolar. Among them, for potent inhibition, Leu was better than Phe and Val as the P1' amino acid, and the P2' position amino acid was necessary, and preferentially Phe. Insertion of the Pn peptide into 4d or 4k, giving compounds 5a-c, did not increase the activities of 4d and 4k. Substitution of the mercapto group with other functional groups lost the activity of compound 4a. The stereochemical preference at the thiol-attached position was also determined by preparation of both isomers of 4a. It was found that the S configuration compound (36b) is approximately 100 times more potent than the corresponding R-isomer (36a).

New selective cytotoxic diterpenylquinones and diterpenylhydroquinones.

A new series of diterpenylquinone/hydroquinones has been prepared by Diels-Alder cycloaddition between three labdanic diterpenoids (myrceocommunic acid, methyl myrceocommunate, and myrceocommunyl acetate) and p-benzoquinone or 1,4-naphthoquinone. Influences of the quinone/hydroquinone fragment and other structural features, such as the different functionalities in the terpenic core, are considered in relation to the cytotoxicity toward neoplastic cells and the selectivity of these diterpenylnaphthoquinones/hydroquinones and anthraquinones. Several compounds showed IC50 values under the micromolar level, and four of these derivatives were evaluated at the NCI screening panel. The results showed an important selectivity toward renal cancer lines, identifying these compounds as a very promising group of antineoplastics.

Patent Evaluation: Azadecalin Amides as Cholesterol Biosynthesis Inhibitors

SummaryNovelty: Azadecalin amides and thioamides are disclosed. These compounds are said to inhibit cholesterol biosynthesis by virtue of their squalene epoxidase and/or oxidosqualene cyclase inhibitory activity and are potentially useful for the prevention of arteriosclerosis.Biology: Oxidosqualene cyclase inhibition was demonstrated in vitro in HepG2 cells and against purified liver microsomal enzyme; two selected compounds showed IC50 values of 0.7 and 52.0 μM.Chemistry: Synthesis of the compounds is outlined in a multistep preparative scheme which is exemplified in seventeen cases. The compound N-[1-oxo-5-(3-methyl-butylmercapto)pentyl]-8-aza-4α,10-dimethyl-trans-decalin-3β-ol is specifically claimed.Structure: