Discovery of novel 4-anilinoquinazoline derivatives as potent inhibitors of epidermal growth factor receptor with antitumor activity

Two new series of new compounds containing a 6-amino-substituted group or 6-acrylamide-substituted group linked to a 4-anilinoquinazoline nucleus have been discovered as potential EGFR inhibitors. These compounds proved efficient effects on antiproliferative activity and EGFR–TK inhibitory activity. Especially, N⁶-((5-bromothiophen-2-yl)methyl)-N⁴-(3-chlorophenyl)quinazoline-4,6-diamine (5e), showed the most potent inhibitory activity (IC₅₀ = 3.11 μM for Hep G2, IC₅₀ = 0.82 μM for A549). The EGFR molecular docking model suggested that the new compound is nicely bound to the region of EGFR, and cell morphology by Hoechst stain experiment suggested that these compounds efficiently induced apoptosis of A549 cells.     

Design,synthesis and biological evaluation of thiazolidinone derivatives as potential EGFR and HER-2 kinase inhibitors

Two series of thiazolidinone derivatives designing for potential EGFR and HER-2 kinase inhibitors have been discovered. Some of them exhibited significant EGFR and HER-2 inhibitory activity. Compound 2-(2-(5-bromo-2-hydroxybenzylidene)hydrazinyl)thiazol-4(5H)-one (12) displayed the most potent inhibitory activity (IC₅₀ = 0.09 μM for EGFR and IC₅₀ = 0.42 μM for HER-2), comparable to the positive control erlotinib. Docking simulation was performed to position compound 12 into the EGFR active site to determine the probable binding model. Antiproliferative assay results indicating that some of the thiazolidinone derivatives own high antiproliferative activity against MCF-7. Compound 12 with potent inhibitory activity in tumor growth inhibition would be a potential anticancer agent.     

Design,synthesis, and docking studies of afatinib analogs bearing cinnamamide moiety as potent EGFR inhibitors

Two series of afatinib derivatives bearing cinnamamide moiety (10a–n and 11a–h) were designed, synthesized and evaluated for the IC₅₀ values against four cancer cell lines (A549, PC-3, MCF-7 and Hela). Two selected compounds (10e, 10k) were further evaluated for the inhibitory activity against EGFR and VEGFR2/KDR kinases. Seven of the compounds showed excellent cytotoxicity activity and selectivity with the IC₅₀ values in single-digit μM to nanomole range. Three of them are equal to more active than positive control afatinib against one or more cell lines. The most promising compound 10k showed the best activity against A549, PC-3, MCF-7 and Hela cancer cell lines and EGFR kinase, with the IC₅₀ values of 0.07 ± 0.02 μM, 7.67 ± 0.97 μM, 4.65 ± 0.90 μM and 4.83 ± 1.28 μM, which were equal to more active than afatinib (0.05 ± 0.01 μM, 4.1 ± 2.47 μM, 5.83 ± 1.89 μM and 6.81 ± 1.77 μM), respectively. Activity of compounds 10e (IC₅₀ 9.1 nM) and 10k (IC₅₀ 3.6 nM) against EGFR kinase were equal to the reference compound afatinib (IC₅₀ 1.6 nM). Structure–activity relationships (SARs) and docking studies indicated that replacement of the aqueous solubility 4-(dimethylamino)but-2-enamide group by cinnamamide moiety didn’t decrease the antitumor activity. The results suggested that methoxy substitution had a significant impact on the activity and methoxy substituted on C-4 or C-2,3,4 position was benefit for the activity.     

5-Nitro-2-furfuriliden derivatives as potential anti-Trypanosoma cruzi agents: Design,synthesis, bioactivity evaluation,cytotoxicity and exploratory data analysis

The anti-Trypanosoma cruzi activity of 5-nitro-2-furfuriliden derivatives as well as the cytotoxicity of these compounds on J774 macrophages cell line and FN1 human fibroblast cells were investigated in this study. The most active compounds of series I and II were 4-butyl-[N′-(5-nitrofuran-2-yl) methylene] benzidrazide (3g; IC₅₀ = 1.05 μM ± 0.07) and 3-acetyl-5-(4-butylphenyl)-2-(5-nitrofuran-2-yl)-2,3-dihydro,1,3,4-oxadiazole (4g; IC₅₀ = 8.27 μM ± 0.42), respectively. Also, compound 3g was more active than the standard drugs, benznidazole (IC₅₀ = 22.69 μM ± 1.96) and nifurtimox (IC₅₀ = 3.78 μM ± 0.10). Regarding the cytotoxicity assay, the 3g compound presented IC₅₀ value of 28.05 μM (SI = 26.71) against J774 cells. For the FN1 fibroblast assay, 3g showed IC₅₀ value of 98 μM (SI = 93.33). On the other hand, compound 4g presented a cytotoxicity value on J774 cells higher than 400 μM (SI >48), and for the FN1 cells its IC₅₀ value was 186 μM (SI = 22.49). Moreover, an exploratory data analysis, which comprises hierarchical cluster (HCA) and principal component analysis (PCA), was carried out and the findings were complementary. The molecular properties that most influenced the compounds’ grouping were C log P and total dipole moment, pointing out the need of a lipophilic/hydrophilic balance in the designing of novel potential anti-T. cruzi molecules.     

Synthesis,biological evaluation,and molecular docking studies of novel 2-styryl-5-nitroimidazole derivatives containing 1,4-benzodioxan moiety as FAK inhibitors with anticancer activity

A series of 2-styryl-5-nitroimidazole derivatives containing 1,4-benzodioxan moiety (3a–3r) has been designed, synthesized and their biological activities were also evaluated as potential antiproliferation and focal adhesion kinase (FAK) inhibitors. Among all the compounds, 3p showed the most potent activity in vitro which inhibited the growth of A549 with IC₅₀ value of 3.11 μM and Hela with IC₅₀ value of 2.54 μM respectively. Compound 3p also exhibited significant FAK inhibitory activity (IC₅₀ = 0.45 μM). Docking simulation was performed for compound 3p into the FAK structure active site to determine the probable binding model.     

Design,synthesis and biological evaluation of novel 6-alkenylamides substituted of 4-anilinothieno[2,3-d]pyrimidines as irreversible epidermal growth factor receptor inhibitors

A novel series of 6-alkenylamides of 4-anilinothieno[2,3-d]pyrimidine derivatives was designed, synthesized and evaluated as irreversible inhibitors of the epidermal growth factor receptor (EGFR). Most of the compounds exhibited good potency against EGFR wild type (EGFR wt) and EGFR T790M/L858R. Among these, the half-maximal inhibitory concentration (IC₅₀) values of 17 compounds against EGFR wt were less than 0.020 μM, and those of 12 compounds were less than 0.010 μM. The IC₅₀ values of 10 compounds against EGFR T790M/L858R were less than 0.005 μM. Compounds 8l, 9n, 9o, 9q and 9v almost completely blocked the phosphorylation of EGFR in the A431 cell line at 1 μM. Compounds 8l, 9n, 9o, 9q and 9v blocked the autophosphorylation of EGFR in NCI-H1975 cells at high concentration (1 μM), and compound 8l was confirmed to be an irreversible inhibitor through the dilution method.     

Design,synthesis and molecular modeling of biquinoline–pyridine hybrids as a new class of potential EGFR and HER-2 kinase inhibitors

A new series of biquinoline–pyridine hybrids were designed and synthesized by a base-catalyzed cyclocondensation through one-pot multicomponent reaction. All compounds were tested for in vitro anticancer activities against two cancer cell lines A549 (adenocarcinomic human alveolar basal epithelial) and Hep G2 (liver cancer). Enzyme inhibitory activities of all compounds were carried out against EGFR and HER-2 kinase. Of the compounds studied, majority of the compounds showed effective anticancer activity against used cancer cell lines. Compound 9i (IC₅₀ = 0.09 μM) against EGFR and (IC₅₀ = 0.2 μM) against HER-2 kinase displayed the most potent inhibitory activity as compared to other member of the series. In the molecular modelling study, compound 9i was bound in to the active pocket of EGFR with four hydrogen bonds and two π–cation interactions having minimum binding energy ΔG_b = −54.4 kcal/mol.     

Design,synthesis and cytotoxic activity of novel sulfonylurea derivatives of podophyllotoxin

Three series of novel sulfonylurea podophyllotoxin derivatives were designed, synthesized, and evaluated for in vitro cytotoxicity against four tumor cell lines (A-549, DU-145, KB and KBvin). Compounds 14c (IC₅₀: 1.41–1.76 μM) and 14e (IC₅₀: 1.72–2.01 μM) showed superior cytotoxic activity compared with etoposide (IC₅₀: 2.03 to >20 μM), a clinically available anticancer drug. Significantly, most of the compounds exhibited comparable cytotoxicity against the drug-resistant tumor cell line KBvin, while etoposide lost activity completely. Preliminary structure–activity relationship (SAR) correlations indicated that the 4′-O-methyl functionality in podophyllotoxin analogues may be essential to maintain cytotoxic activity, while an arylsulfonylurea side chain at podophyllotoxin’s 4β position can significantly improve cytotoxic activity.     

Two polymethoxylated flavonoids with antioxidant activities and a rearranged clerodane diterpenoid from the leaf exudates of Microglossa pyrifolia

Three novel compounds; two polymethoxylated flavonoids, 5,7,4′-trihydroxy-3,8,3′,5′-tetramethoxyflavone (1), 5,7,3′-trihydroxy-3,8,4′,5′-trimethoxyflavone (2), and a clerodane diterpenoid; 8-acetoxyisochiliolide lactone (3) were characterized from the leaf exudates of Microglossa pyrifolia. In addition, three known polymethoxylated flavonoids including; 5,7,4′-trihydroxy-3,8,3′-trimethoxyflavone (4), 5,3′4′-trihydroxy-3,7,8-trimethoxyflavone (5), 5,3′4′-trihydroxy-7-methoxyflavanone (6) and a clerodane diterpenoid; 7,8-epoxyisocholiolide lactone (7) were identified. Their structures were determined on the basis of spectroscopic evidence. All the compounds did not exhibit antiplasmodial and antimicrobial activities at 47.6 μg/mL and were not cytotoxic at 5 μg/mL. Compound 6 exhibited modest antileishmanial activity with IC₅₀ value of 13.13 μg/mL with 5 and 7 showing activities with IC₅₀ values of 31.13 and 38.00 μg/mL, respectively, therefore inactive. The flavonoids (quercetin derivatives, 4 and 5) showed similar antioxidant activities, using 2,2-diphenylpicrylhydrazyl (DPPH) assay, with IC₅₀ values of 6.2 ± 0.3 μg/mL for 4 (17.3 μM) and 5 (17.8 μM) respectively. These activities were comparable to that of the standard quercetin (IC₅₀ value of 6.0 ± 0.2 μg/mL (19.9 μM)), irrespective of methylation of the characteristic hydroxyl groups expected to be responsible for activity and additional substitution at C-8 in ring A of the flavonoid ring. These studies revealed that the presence of an hydroxyl group at C-4′ positions and oxygenation at C-3 in flavone skeleton, appears to be necessary for good antioxidant activities as encountered in compounds 1, 4 and 5. Substantial reduction in antioxidant activity was shown by methoxylation of the 4′-OH as observed in compound 2 with an IC₅₀ value of 8.79 ± 0.3 μg/mL (24.4 μM).     

Incrassamarin A–D: Four new 4-substituted coumarins from Calophyllum incrassatum and their biological activities

Four new 4-substituted coumarins, incrassamarin A (1), B (2), C (3) and D (4) with (7S,8S)-7,8-dihydro-5-hydroxy-7,8-dimethyl-4-propyl-2H,6H-benzo[1,2-b;5,4-b’]dipyran-2,6-dione (5), friedelin, carpachromene, amentoflavone, epiafzelechin and L-quercitrin were isolated from the barks and leaves of Calophyllum incrassatum (Guttiferae). The compounds were isolated and purified by size-exclusion recycling HPLC and column chromatographic techniques. The structures of the compounds were determined by spectroscopic means. The compounds were tested for their cytotoxic activity towards MCF-7 and A-549 cell lines and α-glucosidase enzymatic inhibitory activity. Compound (1) displayed cytotoxic activity against A-549 cell lines with IC₅₀ 87.71 μg/mL and showed inhibition towards α-glucosidase enzymatic activity with IC₅₀ 93.25 μM. This is the first report on the isolation of phytochemicals from the barks and leaves of C. incrassatum and their bioactivities.     

Synthesis and antiproliferative activity of two diastereomeric lignan amides serving as dimeric caffeic acid-l-DOPA hybrids

Two new diastereomeric lignan amides (4 and 5) serving as dimeric caffeic acid-l-DOPA hybrids were synthesized. The synthesis involved the FeCl₃-mediated phenol oxidative coupling of methyl caffeate to afford trans-diester 1a as a mixture of enantiomers, protection of the catechol units, regioselective saponification, coupling with a suitably protected l-DOPA derivative, separation of the two diastereomers thus obtained by flash column chromatography and finally global chemoselective deprotection of the catechol units. The effect of hybrids 4 and 5 and related compounds on the proliferation of two breast cancer cell lines with different metastatic potential and estrogen receptor status (MDA-MB-231 and MCF-7) and of one epithelial lung cancer cell line, namely A-549, was evaluated for concentrations ranging from 1 to 256 μM and periods of treatment of 24, 48 and 72 h. Both hybrids showed interesting and almost equipotent antiproliferative activities (IC₅₀ 64–70 μM) for the MDA-MB-231 cell line after 24–48 h of treatment, but they were more selective and much more potent (IC₅₀ 4–16 μM) for the MCF-7 cells after 48 h of treatment. The highest activity for both hybrids and both breast cancer lines was observed after 72 h of treatment (IC₅₀ 1–2 μM), probably as the result of slow hydrolysis of their methyl ester functions.     

Design,modification and 3D QSAR studies of novel naphthalin-containing pyrazoline derivatives with/without thiourea skeleton as anticancer agents

Two series of novel naphthalin-containing pyrazoline derivatives C1–C14 and D1–D14 have been synthesized and evaluated for their EGFR/HER-2 inhibitory and anti-proliferation activities. Compound D14 displayed the most potent activity against EGFR and A549 cell line (IC₅₀ = 0.05 μM and GI₅₀ = 0.11 μM), being comparable with the positive control Erlotinib (IC₅₀ = 0.03 μM and GI₅₀ = 0.03 μM) and more potent than our previous compounds C0–A (IC₅₀ = 5.31 μM and GI₅₀ = 33.47 μM) and C0–B (IC₅₀ = 0.09 μM and GI₅₀ = 0.34 μM). Meanwhile, compound C14 displayed the most potent activity against HER-2 and MCF-7 cell line (IC₅₀ = 0.88 μM and GI₅₀ = 0.35 μM), being a little less potent than Erlotinib (IC₅₀ = 0.16 μM and GI₅₀ = 0.08 μM) but far more potent than C0–A (IC₅₀ = 6.58 μM and GI₅₀ = 27.62 μM) and C0–B (IC₅₀ = 2.77 μM and GI₅₀ = 3.79 μM). The docking simulation was performed to analyze the probable binding models and the QSAR models were built for reasonable design of EGFR/HER-2 inhibitors at present and in future. The structural modification of introducing naphthalin moiety reinforced the combination of our compounds and the receptor, resulting in progress of bioactivity. Moreover, the replacement of thiourea skeleton by using benzene ring resulted in the slight diversity of the two series towards specific targets.     

New coumestan and coumaronochromone derivatives from Dalbergia boehmii Taub. (Fabaceae)

Chemical investigation of leaves and heartwood of Dalbergia boehmii resulted in the isolation of two new phenolic compounds, designated dalbergestan (1) and dalbergichromone (2), along with eleven known compounds, carpachromene (3), proanthocyanidin A-2 (4); piceatannol (5); biochanin A (6); macckiain (7); homopterocarpin (8); angolensin (9); medicarpin (10); 2′,7-dihydroxy-4′,5′-dimethoxyisoflavone (11); 2′-methoxyformononetin (12); and genistein (13). The structures of the new compounds were elucidated on the basis of extensive spectroscopic analyses including, IR, UV, 1D and 2D – NMR as well as HRMS data. Some of the isolated compounds were evaluated for their in vitro insulin secretion activity on isolated mice islets, leishmanicidal activity against L. major (DESTO) promastigotes and in vitro cytotoxicity on MCF-7 cell lines. All tested compounds were inactive on glucose-stimulated insulin secretion at stimulatory glucose (20.0 mM) from MIN6 cells. Compounds 3 (IC₅₀, 70.0 μg/ml), 6 (IC₅₀, 60.3 μg/ml), 7 (IC₅₀, 86.5 μg/ml) and 13 (IC₅₀, 62.6 μg/ml) exhibited low leishmanicidal activity while compound 12 (IC₅₀, 56.8 μg/ml) displayed a moderate activity. Compounds 3 and 5 were found to be active against MCF-7 at 50 μM with IC₅₀ value 33.2 ± 3.79 μg/ml and 42.64 ± 5.05 μg/ml respectively.     

Design,synthesis and biological evaluation of N,N-3-phenyl-3-benzylaminopropanamide derivatives as novel cholesteryl ester transfer protein inhibitor

A series of N,N-3-phenyl-3-benzylaminopropanamide derivatives were identified as novel CETP (cholesteryl ester transfer protein) inhibitors. In our previous study, lead compound L10 was discovered by pharmacophore-based virtual screening (Dong-Mei Zhao et al., 2014). Based on L10 (IC₅₀ 8.06 μM), compound HL6 (IC₅₀ 10.7 μM) was discovered following systematic structure variation and biological tests. Further optimization of the structure–activity relationship (SAR) resulted in N,N-3-phenyl-3-benzylaminopro panamides derivatives as novel CETP inhibitors. They were synthesized and evaluated against CETP by BODIPY-CE fluorescence assay. Among them, HL16 (IC₅₀ 0.69 μM) was a highly potent CETP inhibitor in vitro. In addition, HL16 exhibited favorable HDL-C enhancement and LDL-C reduction in vivo by hamster. The molecular docking of HL16 into the CETP was performed. The binding mode demonstrated that HL16 occupied the CETP binding site and formed interactions with the key amino acid residues.     

Design,synthesis and biological evaluation of novel 4-anilinoquinazolines with C-6 urea-linked side chains as inhibitors of the epidermal growth factor receptor

A novel series of anilinoquinazoline compounds with C-6 urea-linked side chains was designed and synthesized as reversible inhibitors of epidermal growth factor receptor (EGFR) based on the structure–activity relationships (SARs) of anilinoquinazoline inhibitors. All compounds demonstrated good inhibition of EGFR wild type (EGFR wt) (IC₅₀ = 0.024–1.715 μM) and inhibited proliferation of A431cell line (IC₅₀ = 0.116–22.008 μM). The binding mode of compounds 8a, 8d, 8k and 8o was consistent with the biological results. Moreover, compounds 8k and 8l almost completely blocked the phosphorylation of EGFR in A431 cell line at 0.01 μM. Interestingly, all of the compounds also demonstrated moderate inhibition of EGFR/T790M/L858R (IC₅₀ = 0.049–5.578 μM). In addition, compounds 8f and 8h blocked the autophosphorylation of EGFR in NCI-H1975 cells at high concentration (10 μM), and compound 8f was confirmed to be an irreversible inhibitor through the dilution method. Importantly, the compounds with C-6 urea-linked side chains which did not contain Michael acceptors demonstrated moderate to strong irreversible EGFR inhibition.     

Aspernolides F and G,new butyrolactones from the endophytic fungus Aspergillus terreus

Two new butyrolactones: aspernolides F (6) and G (7), together with three stigmasterol derivatives: (22E,24R)-stigmasta-5,7,22-trien-3-β-ol (1), stigmast-4-ene-3-one (2), and stigmasta-4,6,8(14), 22-tetraen-3-one (3), two meroterpenoids: terretonin A (4) and terretonin (5), and a butyrolactone derivative: butyrolactone VI (8) have been isolated from the endophytic fungus Aspergillus terreus isolated from the roots of Carthamus lanatus (Asteraceae). Their structures were determined by spectroscopic means (1D, 2D NMR, and HRESIMS), as well as optical rotation measurement and comparison with literature data. The isolated compounds were evaluated for their anti-microbial, anti-malarial, anti-leishmanial, and cytotoxic activities. Compound 1 displayed a potent activity against MRSA and C. neoformans with IC₅₀ values of 0.96 μg/mL and 4.38 μg/mL, respectively compared to ciprofloxacin (IC₅₀ 0.07 μg/mL) and amphotericin B (IC₅₀ 0.34 μg/mL), respectively. While, 6 showed good activity against C. neoformans (IC₅₀ 5.19 μg/mL) and mild activity against MRSA (IC₅₀ 6.39 μg/mL). Moreover, 1 and 2 exhibited very good anti-leishmanial activity towards L. donovani with IC₅₀ values of 4.61 and 6.31 μg/mL, respectively and IC₉₀ values of 6.02 and 16.71 μg/mL, respectively.     

Schiff’s base derivatives bearing nitroimidazole and quinoline nuclei: New class of anticancer agents and potential EGFR tyrosine kinase inhibitors

New Schiff’s base derivatives 5a–j have been synthesized by reaction between 2-phenoxyquinoline-3-carbaldehydes 3a–j and 2-(2-methyl-5-nitro-1H-imidazol-1-yl)acetohydrazide 4 in presence of nickel(II) nitrate as a catalyst in ethanol under reflux in good yield (78–92%). All compounds were tested for anticancer and inhibition of EGFR. Of the compounds studied, majority of the compounds showed effective antiproliferation and inhibition of EGFR and HER-2 activities. Compound 5h showed most effective inhibition (IC₅₀ = 0.12 ± 0.05 μM) by binding in to the active pocket of EGFR receptor with minimum binding energy (ΔG_b = −58.3691 kcal/mol). The binding was stabilized by two hydrogen bonds, two π–cation and one π–sigma interactions. Compound 5d showed most effective inhibition (IC₅₀ = 0.37 ± 0.04 μM).     

Synthesis and biological evaluation of compounds which contain pyrazole,thiazole and naphthalene ring as antitumor agents

A series of compounds which contain pyrazole, thiazole and naphthalene ring (1a–7a, 1b–7b, 1c–7c, 1d–7d) were firstly synthesized and their anti-proliferative activity, EGFR inhibitory activity, cytotoxicity and inhibition to Hela cell migration were evaluated. Compound 2-(3-(3,4-dimethylphenyl)-5-(naphthalen-2-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazol-4(5H)-one (7d) displayed the most potent inhibitory activity (IC₅₀ = 0.86 μM for Hela and IC₅₀ = 0.12 μM for EGFR). Structure–activity relationship (SAR) analysis showed that the anti-proliferative activity was affected by A-ring-substituent (–OCH₃ > –CH₃ > –H > –Br > –Cl > –F). Docking simulation of compound 7d into EGFR active site showed that naphthalene ring of 7d with LYS721 formed two p–π bonds, which enhanced antitumor activity. Therefore, compound 7d may be developed as a potential antitumor agent.     

Synthesis of dammarane-type triterpene derivatives and their ability to inhibit HIV and HCV proteases

We synthesized dammarane-type triterpene derivatives and evaluated their ability to inhibit HIV-1 and HCV proteases to understand their structure–activity relationships. All of the mono- and di-succinyl derivatives (5a–5f) were powerful inhibitors of HIV-1 protease (IC₅₀ < 10 μM). However, only di-succinyl (5e) and 2,3-seco-2,3-dioic acid (3b) derivatives similarly inhibited HCV protease (IC₅₀ < 10 μM). A-nor dammarane-type triterpenes (4a and 4b, IC₅₀ 10.0 and 29.9 μM, respectively) inhibited HIV-1 protease moderately or strongly, but were inactive against HCV protease. All compounds that powerfully inhibited HIV-1 or HCV protease did not appreciably inhibit the general human proteases, renin and trypsin (IC₅₀ > 1000 μM). These findings indicated that the mono-succinyl dammarane type derivatives (5a–5d) selectively inhibited HIV-1 protease and that the di-succinyl (5e, 5f) as well as 2,3-seco-2,3-dioic acid (3b) derivatives preferably inhibited both viral proteases.     

Design,synthesis, and docking studies of phenylpicolinamide derivatives bearing 1H-pyrrolo[2,3-b]pyridine moiety as c-Met inhibitors

Four series of phenylpicolinamide derivatives bearing 1H-pyrrolo[2,3-b]pyridine moiety (12a–e, 13a–f, 14a–f and 15a–i) were designed, synthesized and evaluated for the IC₅₀ values against three cancer cell lines (A549, PC-3 and MCF-7) and c-Met kinase. Five selected compounds (13b, 15b, 15d, 15e and 15f) were further evaluated for the activity against HepG2 and Hela cell lines. Eighteen of the compounds showed excellent cytotoxicity activity and selectivity with the IC₅₀ valuables in single-digit μM to nanomole range. Seven of them are equal to more active than positive control Foretinib against one or more cell lines. The most promising compound 15f showed superior activity to Foretinib, with the IC₅₀ values of 1.04 ± 0.11 μM, 0.02 ± 0.01 μM and 9.11 ± 0.55 μM against A549, PC-3 and MCF-7 cell lines, which were 0.62 to 19.5 times more active than Foretinib (IC₅₀ values: 0.64 ± 0.26 μM, 0.39 ± 0.11 μM, 9.47 ± 0.22 μM), respectively. Structure–activity relationships (SARs) and docking studies indicated that replacement of quinoline nucleus of the previous active compounds with 1H-pyrrolo[2,3-b]pyridine moiety maintained even improved the potent cytotoxic activity. The results suggested that the introduction of fluoro atoms to the aminophenoxy part of target compounds or the phenyl group of pyrimidine substituted on C-4 position was benefit for the activity.