Discovery of a series of 8-(1-phenylpyrrolidin-2-yl)-6-carboxamide-2-morpholino-4H-chromen-4-one as PI3Kß/δ inhibitors for the treatment of PTEN-deficient tumours.

Attempts to lock the active conformation of compound 4, a PI3Kß/δ inhibitor (PI3Kß cell IC50 0.015µM), led to the discovery of a series of 8-(1-phenylpyrrolidin-2-yl)-6-carboxamide-2-morpholino-4H-chromen-4-ones, which showed high levels of potency and selectivity as PI3Kß/δ inhibitors. Compound 10 proved exquisitely potent and selective: PI3Kß cell IC50 0.0011µM in PTEN null MDA-MB-468 cell and PI3Kδ cell IC50 0.014µM in Jeko-1 B-cell, and exhibited suitable physical properties for oral administration. In vivo, compound 10 showed profound pharmacodynamic modulation of AKT phosphorylation in a mouse PTEN-null PC3 prostate tumour xenograft after a single oral dose and gave excellent tumour growth inhibition in the same model after chronic oral dosing. Based on these results, compound 10 was selected as one of our PI3Kß/δ preclinical candidates.

Discovery of a series of 8-(2,3-dihydro-1,4-benzoxazin-4-ylmethyl)-2-morpholino-4-oxo-chromene-6-carboxamides as PI3Kß/δ inhibitors for the treatment of PTEN-deficient tumours.

We report the discovery and optimisation of a series of 8-(2,3-dihydro-1,4-benzoxazin-4-ylmethyl)-2-morpholino-4-oxo-chromene-6-carboxamides, leading to compound 16 as a potent and selective PI3Kß/δ inhibitor: PI3Kß cell IC50 0.012 µM (in PTEN null MDA-MB-468 cell) and PI3Kδ cell IC50 0.047 µM (in Jeko-1 B-cell), with good pharmacokinetics and physical properties. In vivo, 16 showed profound pharmacodynamic modulation of AKT phosphorylation in a mouse PTEN-deficient PC3 prostate tumour xenograft after a single oral dose and gave excellent tumour growth inhibition in the same model after chronic oral dosing. Compound 16 was selected as a preclinical candidate for the treatment of PTEN-deficient tumours.

Investigation of (E)-3-[4-(2-Oxo-3-aryl-chromen-4-yl)oxyphenyl]acrylic Acids as Oral Selective Estrogen Receptor Down-Regulators.

A novel estrogen receptor down-regulator, 7-hydroxycoumarin (5, SS5020), has been reported with antitumor effects against chemically induced mammary tumors. Here, we report on our own investigation of 7-hydroxycoumarins as potential selective estrogen receptor down-regulators, which led us to the discovery of potent down-regulating antagonists, such as 33. Subsequent optimization and removal of the 7-hydroxy group led to coumarin 59, which had increased potency and improved rat bioavailability relative to SS5020.

Discovery of (R)-8-(1-(3,5-difluorophenylamino)ethyl)-N,N-dimethyl-2-morpholino-4-oxo-4H-chromene-6-carboxamide (AZD8186): a potent and selective inhibitor of PI3Kß and PI3Kδ for the treatment of PTEN-deficient cancers.

Several studies have highlighted the dependency of PTEN deficient tumors to PI3Kß activity and specific inhibition of PI3Kδ has been shown activity against human B-cell cancers. We describe the discovery and optimization of a series of 8-(1-anilino)ethyl)-2-morpholino-4-oxo-4H-chromene-6-carboxamides as PI3Kß/δ inhibitors, which led to the discovery of the clinical candidate 13, also known as AZD8186. On the basis of the lower lipophilicity of the chromen-4-one core compared to the previously utilized pyrido[1,2-a]pyrimid-4-one core, this series of compounds displayed high metabolic stability and suitable physical properties for oral administration. Compound 13 showed profound pharmacodynamic modulation of p-Akt in PTEN-deficient PC3 prostate tumor bearing mice after oral administration and showed complete inhibition of tumor growth in the mouse PTEN-deficient PC3 prostate tumor xenograft model. 13 was selected as a clinical candidate for treatment of PTEN-deficient cancers and has recently entered phase I clinical trials.

Discovery of 9-(1-anilinoethyl)-2-morpholino-4-oxo-pyrido[1,2-a]pyrimidine-7-carboxamides as PI3Kß/δ inhibitors for the treatment of PTEN-deficient tumours.

Starting from TGX-221, we designed a series of 9-(1-anilinoethyl)-2-morpholino-4-oxo-pyrido[1,2-a]pyrimidine-7-carboxamides as potent and selective PI3Kß/δ inhibitors. Structure-activity relationships and structure-property relationships around the aniline and the amide substituents are discussed. We identified compounds 17 and 18, which showed profound pharmacodynamic modulation of phosphorylated Akt in the PC3 prostate tumour xenograft, after a single oral dose. Compound 17 also gave significant inhibition of tumour growth in the PC3 prostate tumour xenograft model after chronic oral dosing.

Discovery of new quinoline ether inhibitors with high affinity and selectivity for PDGFR tyrosine kinases.

A new series of quinoline ether inhibitors, which potently and selectively inhibit PDGFR tyrosine kinases, is described in this Letter. Compounds 23 and 33 are selective, low nanomolar inhibitors of PDGFRα and ß, display good pharmacokinetics in rat and dog and are active in vivo at low doses when given orally twice daily. Further evaluation of these compounds is warranted.

Discovery of AZD2932, a new Quinazoline Ether Inhibitor with high affinity for VEGFR-2 and PDGFR tyrosine kinases.

A new series of Quinazoline Ether Inhibitor which potently inhibits VEGFR-2 and PDGFR tyrosine kinases is described here. In vitro, pharmacokinetics and in vivo evaluations led to the selection of AZD2932.

Inhibitors of the tyrosine kinase EphB4. Part 4: Discovery and optimization of a benzylic alcohol series.

Optimization of our bis-anilino-pyrimidine series of EphB4 kinase inhibitors led to the discovery of compound 12 which incorporates a key m-hydroxymethylene group on the C4 aniline. 12 displays a good kinase selectivity profile, good physical properties and pharmacokinetic parameters, suggesting it is a suitable candidate to investigate the therapeutic potential of EphB4 kinase inhibitors.

Preclinical anticancer activity of the potent, oral Src inhibitor AZD0530.

AZD0530, an orally available Src inhibitor, demonstrated potent antimigratory and anti-invasive effects in vitro, and inhibited metastasis in a murine model of bladder cancer. Antiproliferative activity of AZD0530 in vitro varied between cell lines (IC(50) 0.2 ->10µM). AZD0530 inhibited tumor growth in 4/10 xenograft models tested and dynamically inhibited in vivo phosphorylation of Src substrates paxillin and FAK in both growth-inhibition-resistant and -sensitive xenografts. The activity of AZD0530 in NBT-II bladder cancer cells in vitro was consistent with inhibition of cell migration and stabilization of cell-cell adhesion. These data suggest a dominant anti-invasive pharmacology for AZD0530 that may limit tumor progression in a range of cancers. AZD0530 is currently in Phase II clinical trials.

N-(5-chloro-1,3-benzodioxol-4-yl)-7-[2-(4-methylpiperazin-1-yl)ethoxy]-5- (tetrahydro-2H-pyran-4-yloxy)quinazolin-4-amine, a novel, highly selective, orally available, dual-specific c-Src/Abl kinase inhibitor.

Src family kinases (SFKs) are nonreceptor tyrosine kinases that are reported to be critical for cancer progression. We report here a novel subseries of C-5-substituted anilinoquinazolines that display high affinity and specificity for the tyrosine kinase domain of the c-Src and Abl enzymes. These compounds exhibit high selectivity for SFKs over a panel of recombinant protein kinases, excellent pharmacokinetics, and in vivo activity following oral dosing. N-(5-Chloro-1,3-benzodioxol-4-yl)-7-[2-(4-methylpiperazin-1-yl)ethoxy]-5-(tetrahydro-2H-pyran-4-yloxy)quinazolin-4-amine (AZD0530) inhibits c-Src and Abl enzymes at low nanomolar concentrations and is highly selective over a range of kinases. AZD0530 displays excellent pharmacokinetic parameters in animal preclinically and in man (t(1/2) = 40 h). AZD0530 is a potent inhibitor of tumor growth in a c-Src-transfected 3T3-fibroblast xenograft model in vivo and led to a significant increase in survival in a highly aggressive, orthotopic model of human pancreatic cancer when dosed orally once daily. AZD0530 is currently undergoing clinical evaluation in man.

New heterocyclic analogues of 4-(2-chloro-5-methoxyanilino)quinazolines as potent and selective c-Src kinase inhibitors.

A series of 5,7-disubstituted quinazolines, bearing 4-heteroaryl substituents such as 2-pyridinylamine or 2-pyrazinylamine, has been synthetised and evaluated as c-Src kinase inhibitors. Highly potent inhibition, high selectivity and physical properties suitable for oral dosing were achieved within this series: 23d and 42 were identified as sub-0.1muM inhibitors in a c-Src-driven cell proliferation assay and displayed adequate rat pharmacokinetics after oral administration.

Discovery of a new class of anilinoquinazoline inhibitors with high affinity and specificity for the tyrosine kinase domain of c-Src.

Deregulated activity of the nonreceptor tyrosine kinase c-Src is believed to result in signal transduction, cytoskeletal and adhesion changes, ultimately promoting a tumor-invasive phenotype. We report here the discovery of a new class of anilinoquinazoline inhibitors with high affinity and specificity for the tyrosine kinase domain of the c-Src enzyme. Special attention was directed toward finding inhibitors selective against KDR tyrosine kinase in order to ensure that the in vivo profile of a specific Src inhibitor could be determined. The 4-aminobenzodioxole quinazoline series gave compounds with excellent potency and selectivity. The most interesting compounds were evaluated in vivo and displayed good pharmacokinetics following oral dosing. Compounds such as the aminobenzodioxoles were shown to be potent inhibitors of tumor growth in a c-Src-transformed 3T3 xenograft model in vivo, resulting in more than 90% growth inhibition at doses as low as 6 mg/kg po once daily. Src tyrosine kinase inhibitors such as these may provide a novel therapeutic modality for targeting cancer invasion and metastasis.

Novel 4-anilinoquinazolines with C-7 basic side chains: design and structure activity relationship of a series of potent, orally active, VEGF receptor tyrosine kinase inhibitors.

We have previously shown that 4-anilinoquinazolines can be potent inhibitors of vascular endothelial growth factor (VEGF) receptor (Flt-1 and KDR) tyrosine kinase activity. A novel subseries of 4-anilinoquinazolines that possess basic side chains at the C-7 position of the quinazoline nucleus have been synthesized. This subseries contains potent, nanomolar inhibitors of KDR (median IC(50) 0.02 microM, range 0.001-0.04 microM), which are comparatively less potent vs Flt-1 tyrosine kinase (median IC(50) 0.55 microM, range 0.02-1.6 microM). The compounds also retain some inhibitory activity against the tyrosine kinase associated to the endothelial growth factor receptor (EGFR) (median IC(50) 0.2 microM, range 0.075-0.8 microM) but demonstrate selectivity vs that associated to the FGF receptor 1 (median IC(50) 2.5 microM, range 0.9-19 microM). This selectivity profile is also evident in a growth factor-stimulated human endothelial cell (HUVEC) proliferation assay (i.e., inhibition of VEGF > EGF > FGF), with inhibition of VEGF-induced proliferation being achieved at nanomolar concentrations (median IC(50) 0.06 microM). Further examination of compound 2 (ZD6474) in recombinant enzyme assays revealed excellent selectivity for the inhibition of KDR tyrosine kinase (IC(50) 0.04 microM) vs the kinase activity of erbB2, MEK, CDK-2, Tie-2, IGFR-1R, PDK, PDGFRbeta, and AKT (IC(50) range: 1.1 to >100 microM). Anilinoquinazolines possessing basic C-7 side chains exhibited markedly improved aqueous solubility over previously described anilinoquinazolines possessing neutral C-7 side chains (up to 500-fold improvement at pH 7.4). In addition, aqueous solubility of the neutral fraction present at pH 7.4 of the basic subseries of anilinoquinazoline proved to be higher than that of the neutral analogue 1 (ZD4190). Oral administration of representative compounds to mice (50 mg/kg) produced plasma levels between 0.2 and 3 microM at 24 h after dosing. Our development candidate 2 demonstrated a very attractive in vitro profile combined with excellent solubility (330 microM at pH 7.4) and good oral bioavailability in rat and dog (> 80 and > 50%, respectively). This compound demonstrated highly significant, dose-dependent, antitumor activity in athymic mice. Once daily oral administration of 100 mg/kg of compound 2 for 21 days inhibited the growth of established Calu-6 lung carcinoma xenografts by 79% (P < 0.001, Mann Whitney rank sum test), and substantial inhibition (36%, P < 0.02) was evident with 12.5 mg/kg/day.