Indolinone Derivatives Research Articles

Crystal structure of 1-ethyl-5-iodoindolin-2-one

In the title indolinone derivative, C10H10INO, all the non-H atoms, except the terminal methyl C atom, are almost coplanar. The mol-ecules are arranged into columns extending along the a-axis direction and inter-act with the mol-ecules in adjacent columns via C-H⋯O hydrogen bonds [H⋯O distance = 2.57 (3) Å] and I⋯I short contacts of 3.8986 (3) Å. A one-dimensional zigzag iodine chain along the a axis is apparent between two neighbouring columns.

ChemInform Abstract: Catalyst‐ and Chromatography‐Free Synthesis of Pyrrole‐Substituted Indolinone Derivatives in Water.

AbstractThis novel facile protocol allows the synthesis of pyrrole‐substituted indolinone derivatives via addition of amine (II) to isatins followed by decarboxylation and dehydration.

Development and validation of a LC-MS/MS method for assessment of an anti-inflammatory indolinone derivative by in vitro blood-brain barrier models

Development and validation of a LC-MS/MS method for assessment of an anti-inflammatory indolinone derivative by in vitro blood-brain barrier models

Catalyst- and chromatography-free synthesis of pyrrole-substituted indolinone derivatives in water

Pyrrole-substituted indolinone derivatives were synthesized by the reaction of 4-hydroxyproline and isatin derivatives in water under catalyst-free conditions. The main advantages of this protocol besides the use of water as a solvent include short reaction time, practical simplicity, and high yield.

Development and validation of a LC–MS/MS method for assessment of an anti-inflammatory indolinone derivative by in vitro blood–brain barrier models

The compound (E,Z)-3-(4-hydroxy-3,5-dimethoxybenzylidene)indolin-2-one (indolinone) was identified from lipophilic woad extracts (Isatis tinctoria L., Brassicaceae) as a compound possessing potent histamine release inhibitory and anti-inflammatory properties [1]. To further evaluate the potential of indolinone in terms of crossing the blood–brain barrier (BBB), we screened the compound in several in vitro cell-based human and animal BBB models. Therefore, we developed a quantitative LC–MS/MS method for the compound in modified Ringer HEPES buffer (RHB) and validated it according to FDA and EMA guidelines [2,3]. The calibration curve of indolinone in the range between 30.0 and 3000ng/ml was quadratic, and the limit of quantification was 30.0ng/ml. Dilution of samples up to 100-fold did not affect precision and accuracy. The carry-over was within acceptance criteria. Indolinone proved to be stable in RHB for 3h at room temperature (RT), and for three successive freeze/thaw cycles. The processed samples could be stored in the autosampler at 10°C for at least 28h. Moreover, indolinone was stable for at least 16 days in RHB when stored below −65°C. This validation study demonstrates that our method is specific, selective, precise, accurate, and capable to produce reliable results.In the immortalized human BBB mono-culture model, the apparent permeability coefficient from apical to basolateral (PappA→B), and the Papp from basolateral to apical (PappB→A) were 19.2±0.485×10−6cm/s and 21.7±0.326×10−6cm/s, respectively. For the primary rat/bovine BBB co-culture model a PappA→B of 27.1±1.67×10−6cm/s was determined. In the primary rat BBB triple co-culture model, the PappA→B and the PappB→A were 56.2±3.63×10−6cm/s and 34.6±1.41×10−6cm/s, respectively. The data obtained with the different models showed good correlation and were indicative of a high BBB permeation potential of indolinone confirmed by in silico prediction calculations. P-glycoprotein (P-gp) interaction for indolinone was studied with the aid of a calcein-AM uptake assay, and by calculation of the efflux ratio (ER) from the bidirectional permeability assays. For both bidirectional BBB models an ER below 2 was calculated, indicating that no active mediated transport mechanism is involved for indolinone. In porcine brain capillary endothelial cells (PBCECs), the calcein-AM uptake assay demonstrated that indolinone is neither a P-gp substrate nor a P-gp inhibitor and is accumulated into cells at high extent.

Gold nanoparticles assisted formation of cobalt species for intermolecular hydroaminomethylation and intramolecular cyclocarbonylation of olefins

The intermolecular hydroaminomethylation and the intramolecular cyclocarbonylation efficiently proceeded on cobalt oxide supported gold nanoparticles. The intermolecular reaction employing terminal olefins and N-isopropylaniline afforded hydroaminomethylated products as a mixture of regioisomers via a common reaction path consisting of hydroformylation, imine formation, and hydrogenation. In contrast, indolinone derivatives were exclusively obtained in the case of 2-alkenylanilines based on the intramolecular cyclocarbonylation mechanism. Both of these reactions were catalyzed by cobalt species derived from cobalt oxide. The active cobalt species were formed via reduction of the oxide support promoted by deposited gold nanoparticles. Characterization of the catalysts before and after the reaction was also performed.

Synthesis and pharmacological evaluation of indolinone derivatives as novel ghrelin receptor antagonists

The ghrelin receptor is a G-protein-coupled receptor (GPCR) widely expressed in the brain, stomach and the intestine. It was firstly identified during studies aimed to find synthetic modulators of growth hormone (GH) secretion. GHSR and its endogenous ligand ghrelin were found to be involved in hunger response. Through food intake regulation, they could affect body weight and adiposity. Thus GHSR antagonists rapidly became an attractive target to treat obesity and feeding disorders. In this study we describe the biological properties of new indolinone derivatives identified as a new, chiral class of ghrelin antagonists. Their synthesis as well as the structure–activity relationship will be discussed herein. The in vitro identified compound 14f was a potent GHSR1a antagonist (IC50=7nM). When tested in vivo, on gastric emptying model, 14f showed an inhibitory intrinsic effect when given alone and it dose dependently inhibited ghrelin stimulation. Compound 14f also reduced food intake stimulated both by fasting condition (high level of endogenous ghrelin) and by icv ghrelin. Moreover this compound improved glucose tolerance in ipGTT test.

Development and full validation of an UPLC-MS/MS method for the determination of an anti-allergic indolinone derivative in rat plasma, and application to a preliminary pharmacokinetic study

The natural product (E,Z)-3-(4-hydroxy-3,5-dimethoxybenzylidene)indolin-2-one (indolinone) was identified some years ago as a nanomolar inhibitor of FcɛRI-receptor dependent mast cell degranulation. To further explore the potential of the compound, we established an UPLC-MS/MS assay for dosage in rat plasma. The method was fully validated according to FDA Guidance for industry. Results of this validation and long term stability study demonstrate that the method in lithium heparinized rat plasma is specific, accurate, precise and capable of producing reliable results according to recommendations of international guidelines. The method was validated with a LLOQ of 30.0ng/mL and an ULOQ of 3000ng/mL. The response versus concentration data were fitted with a first order polynomial with 1/X2 weighting. No matrix effect was observed when using three independent sources of rat plasma. The average extraction recovery was consistent over the investigated range. This validation in rat plasma demonstrated that indolinone was stable for 190 days when stored below −65°C; for 4 days at 10°C in the autosampler; for 4h at RT, and during three successive freeze/thaw cycles at −65°C. Preliminary pharmacokinetic data were obtained in male Sprague–Dawley rats (2mg/kg BW i.v.). Blood samples taken from 0 to 12h after injection were collected, and data analyzed with WinNonlin. A short half-life (4.30±0.14min) and a relatively high clearance (3.83±1.46L/h/kg) were found.

ChemInform Abstract: Synthesis and Anticancer Activity of Indolin‐2‐one Derivatives Bearing the 4‐Thiazolidinone Moiety.

AbstractA novel series of the title indolinone derivatives (IX) (16 examples) is synthesized and evaluated in vitro for its cytotoxicity against three human cancer cell lines.

Study of differences in the VEGFR2 inhibitory activities between semaxanib and SU5205 using 3D-QSAR, docking, and molecular dynamics simulations

Semaxanib (SU5416) and 3-[4′-fluorobenzylidene]indolin-2-one (SU5205) are structurally similar drugs that are able to inhibit vascular endothelial growth factor receptor-2 (VEGFR2), but the former is 87 times more effective than the latter. Previously, SU5205 was used as a radiolabelled inhibitor (as surrogate for SU5416) and a radiotracer for positron emission tomography (PET) imaging, but the compound exhibited poor stability and only a moderate IC 50 toward VEGFR2. In the current work, the relationship between the structure and activity of these drugs as VEGFR2 inhibitors was studied using 3D-QSAR, docking and molecular dynamics (MD) simulations. First, comparative molecular field analysis (CoMFA) was performed using 48 2-indolinone derivatives and their VEGFR2 inhibitory activities. The best CoMFA model was carried out over a training set including 40 compounds, and it included steric and electrostatic fields. In addition, this model gave satisfactory cross-validation results and adequately predicted 8 compounds contained in the test set. The plots of the CoMFA fields could explain the structural differences between semaxanib and SU5205. Docking and molecular dynamics simulations showed that both molecules have the same orientation and dynamics inside the VEGFR2 active site. However, the hydrophobic pocket of VEGFR2 was more exposed to the solvent media when it was complexed with SU5205. An energetic analysis, including Embrace and MM-GBSA calculations, revealed that the potency of ligand binding is governed by van der Waals contacts.

Synthesis and biological evaluation of 2-indolinone derivatives as potential antitumor agents

Three series of 3-substituted-indolin-2-ones and azaindolin-2-ones have been synthesized and showed potential antiproliferative activity to cancer cell lines. The inhibition activities on VEGF-induced VEGFR phosphorylation were observed for selected 2-indolinones. Among the compounds synthesized, 5-fluoroindolin-2-one derivative 23 with a pyridone unit showed the most significant enzymatic and cellular activities. Flow cytometric analysis indicates that 23 plays a role in suppressing HCT-116 cell proliferation via G1 phase arrest and apoptosis in a dose dependent manner. The binding mode of compound 23 complexed with VEGFR-2 was predicted using FlexX algorithm. Described here are the chemistry and biological testing for these series which will guide the design and optimization of novel 2-indolione antitumor agents.

Diclofenac metabolism in the mouse: Novel in vivo metabolites identified by high performance liquid chromatography coupled to linear ion trap mass spectrometry

The metabolism of [14C]-diclofenac in mice was investigated following a single oral dose of 10 mg/kg. The majority of the drug-related material was excreted in the urine within 24 h of administration (49.7 %).Liquid chromatographic analyses of urine and faecal extracts revealed extensive metabolism to at least 37 components, with little unchanged diclofenac excreted. Metabolites were identified using a hybrid linear ion-trap mass spectrometer via exact mass determinations of molecular ions and subsequent multi-stage fragmentation.The major routes of metabolism identified included: 1) conjugation with taurine; and 2) hydroxylation (probably at the 4′-and 5-arene positions) followed by conjugation to taurine, glucuronic acid or glucose. Ether, rather than acyl glucuronidation, predominated. There was no evidence for p-benzoquinone-imine formation (i.e. no glutathione or mercapturic acid conjugates were detected).A myriad of novel minor drug-related metabolites were also detected, including ribose, glucose, sulfate and glucuronide ether-linked conjugates of hydroxylated diclofenac derivatives. Combinations of these hydroxylated derivatives with acyl conjugates (glucose, glucuronide and taurine) or N-linked sulfation or glucosidation were also observed. Acyl- or amide-linked-conjugates of benzoic acid metabolites and several indolinone derivatives with further hydroxylated and conjugated moieties were also evident.The mechanisms involved in the generation of benzoic acid and indolinone products indicate the formation reactive intermediates in vivo that may possibly contribute to hepatotoxicity.

Novel Potent Orally Active Multitargeted Receptor Tyrosine Kinase Inhibitors: Synthesis, Structure−Activity Relationships, and Antitumor Activities of 2-Indolinone Derivatives

The inhibition of receptor tyrosine kinases (RTKs) has become a successful approach in the development of anticancer agents. Many potent small-molecule kinase inhibitors have been discovered. We report herein a series of pyrrolo-fused-heterocycle-2-indolinone analogues as inhibitors of vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR), and c-Kit. Among them, some pyrrolo-fused six- and seven-membered-heterocycle derivatives such as 9, 15, 23, and 25 are potent inhibitors of VEGFR, PDGFR, and c-Kit both enzymatically (<50 nM) and cellularly (<50 nM). Furthermore, compounds 9 and 25 possess favorable pharmacokinetic profiles and demonstrate good efficacies against human HT-29 cell colon tumor xenografts in nude mice. Further evaluations are in progress.

ChemInform Abstract: Combined 3D‐QSAR Modeling and Molecular Docking Study on Indolinone Derivatives as Inhibitors of 3‐Phosphoinositide‐Dependent Protein Kinase‐1.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Combined 3D-QSAR Modeling and Molecular Docking Study on Indolinone Derivatives as Inhibitors of 3-Phosphoinositide-Dependent Protein Kinase-1

3-Phosphoinositide-dependent protein kinase-1 (PDK1) is a promising target for developing novel anticancer drugs. In order to understand the structure-activity correlation of indolinone-based PDK1 inhibitors, we have carried out a combined molecular docking and three-dimensional quantitative structure-activity relationship (3D-QSAR) modeling study. The study has resulted in two types of satisfactory 3D-QSAR models, including the CoMFA model (r(2)=0.907; q(2)=0.737) and CoMSIA model (r(2)=0.991; q(2)=0.824), for predicting the biological activity of new compounds. The detailed microscopic structures of PDK1 binding with inhibitors have been studied by molecular docking. We have also developed docking-based 3D-QSAR models (CoMFA with q(2)=0.729; CoMSIA with q(2)=0.79). The contour maps obtained from the 3D-QSAR models in combination with the docked binding structures help to better interpret the structure-activity relationship. All of the structural insights obtained from both the 3D-QSAR contour maps and molecular docking are consistent with the available experimental activity data. This is the first report on 3D-QSAR modeling of PDK1 inhibitors. The satisfactory results strongly suggest that the developed 3D-QSAR models and the obtained PDK1-inhibitor binding structures are reasonable for the prediction of the activity of new inhibitors and in future drug design.

BIBF 1120: Triple Angiokinase Inhibitor with Sustained Receptor Blockade and Good Antitumor Efficacy

Inhibition of tumor angiogenesis through blockade of the vascular endothelial growth factor (VEGF) signaling pathway is a novel treatment modality in oncology. Preclinical findings suggest that long-term clinical outcomes may improve with blockade of additional proangiogenic receptor tyrosine kinases: platelet-derived growth factor receptors (PDGFR) and fibroblast growth factor receptors (FGFR). BIBF 1120 is an indolinone derivative potently blocking VEGF receptor (VEGFR), PDGFR and FGFR kinase activity in enzymatic assays (IC(50), 20-100 nmol/L). BIBF 1120 inhibits mitogen-activated protein kinase and Akt signaling pathways in three cell types contributing to angiogenesis, endothelial cells, pericytes, and smooth muscle cells, resulting in inhibition of cell proliferation (EC(50), 10-80 nmol/L) and apoptosis. In all tumor models tested thus far, including human tumor xenografts growing in nude mice and a syngeneic rat tumor model, BIBF 1120 is highly active at well-tolerated doses (25-100 mg/kg daily p.o.), as measured by magnetic resonance imaging of tumor perfusion after 3 days, reducing vessel density and vessel integrity after 5 days, and inducing profound growth inhibition. A distinct pharmacodynamic feature of BIBF 1120 in cell culture is sustained pathway inhibition (up to 32 hours after 1-hour treatment), suggesting slow receptor off-kinetics. Although BIBF 1120 is rapidly metabolized in vivo by methylester cleavage, resulting in a short mean residence time, once daily oral dosing is fully efficacious in xenograft models. These distinctive pharmacokinetic and pharmacodynamic properties may help explain clinical observations with BIBF 1120, currently entering phase III clinical development.

The chemistry of homophthalic acid: a new synthetic strategy for construction of substituted isocoumarin and indole skeletons

Homophthalic acid was reacted with thionylchloride/DMF and chloroethylformate/NEt 3 in the presence and absence of NaN 3. In all cases completely different isocoumarin derivatives were obtained. These unusual isocoumarin derivatives were isolated and characterized and their formation mechanisms are discussed. The homophthalic acid monomethyl ester was converted into the corresponding isocyanate. Reaction of the isocyanate with different amines produced the urea derivatives. Base-supported condensation reactions of these products gave first an indolinone derivative, which underwent further intermolecular condensation to give substituted indole derivatives. However, when the condensation reaction was carried out in the presence of acetic anhydride, the intermolecular reactions were suppressed. This methodology opens up a new way of synthesizing of various five-membered ring substituted indole derivatives.

Synthesis of 1-(2,6-dichlorophenyl)-3-methylene-1,3-dihydro-indol-2-one derivatives and in vitro anticancer evaluation against SW620 colon cancer cell line

A small library of 2-indolinone derivatives with the 2,6-dichlorophenyl ring at the N 1 position and with varying substitutions including aryl groups at the 3-position were synthesized, and their structures were confirmed by spectral analysis. All molecules were screened for their in vitro cytotoxic activity on SW620 colon cancer cell lines. Among the designed series compounds 4c, 4f and 4j were found to be active at concentrations of 2–15 μg/ml. Some 3D-QSAR models were also built to understand the structure–activity relationship.

Synthesis of novel lactam derivatives and their evaluation as ligands for the dopamine receptors, leading to a D 4-selective ligand

The preparation of some lactam (cyclic amide) derivatives bearing various phenylpiperazinylbutyl side chains attached to the amide nitrogen together with their dopamine receptor affinity study is described. The synthesis of the target compounds involved the preparation of the intermediate bromobutyl derivatives of the appropriate lactam followed by N-alkylation of the appropriate phenylpiperazines with these intermediates. Radioligand binding studies at D 2–D 5 receptor subtypes and a functional calcium assay of the target compounds at D 2 and D 5 receptor subtypes were performed. All compounds, except 12a and 12b, showed selectivity towards the D 2-like receptor subtypes. Selectivity of the indolinone derivatives 11a– d at the D 4 receptors was observed. Compound 11b exhibited a remarkable affinity to hD 4 receptors with K i value of 0.04 ± 0.02 nm and was >43,000-fold selective over the hD 2 receptor. In the functional assay, all the active compounds were of antagonistic activity.

Growth inhibition and induction of apoptosis in acute myeloid leukemia cells by new indolinone derivatives targeting fibroblast growth factor, platelet-derived growth factor, and vascular endothelial growth factor receptors

In acute myeloid leukemia (AML), receptor tyrosine kinase ligands promote growth and survival and contribute to AML-associated marrow neoangiogenesis. We have tested simultaneous inhibition of vascular endothelial growth factor, fibroblast growth factor, and platelet-derived growth factor receptor signaling by novel indolinone derivatives using 14 myeloid, including 11 human leukemic, cell lines. Compounds inhibited colony formation of all cell lines in a dose-dependent fashion. Inhibitory concentrations for 50% of the colony formation/survival (IC50) for BIBF1000 were <100 nmol/L for 3 of 11, <or=500 nmol/L for 6 of 11, and <1,000 nmol/L for 10 of 11 leukemic cell lines, with one cell line being resistant in the dose range <1,000 nmol/L. BIBF1120 was less effective with 4 of 11 leukemic cell lines being resistant within the dose range <1,000 nmol/L. Testing of myeloid 32D cells transfected with empty vector, wild-type Flt3, or Flt3 carrying an internal tandem duplication mutation revealed higher resistance for the internal tandem duplication mutant. These effects of the compounds were associated with inhibition of tyrosine phosphorylation and the mitogen-activated protein kinase pathway. Furthermore, both compounds induced apoptosis in the sensitive cell lines. In Mono-Mac1 cells, the compounds had a direct proapoptotic effect that was increasing the proapoptotic effect of 1-beta-D-arabinofuranosylcytosine. The data provide a rationale for clinical evaluation of these tyrosine kinase inhibitors in AML.