Yoshikazu Uto

Hypoxia-inducible factor inhibitors: a survey of recent patented compounds (2004 -- 2010)

Introduction: Hypoxia-inducible factor (HIF) is a heterodimeric transcription factor consisting of α and β subunits that regulates the expression of angiogenic factors, including VEGF, which are involved in angiogenesis, invasion/metastasis, glucose uptake and cell survival during cancer development. Areas covered: This review summarizes the information about patented HIF inhibitors over the last 7 years (2004 – 2010). The reader will gain an outline of the structure and biological activity of recently developed HIF inhibitors. Expert opinion: Inhibition of HIF is an attractive therapeutic target for tumor angiogenesis and, until now, various HIF inhibitors have been discovered and evaluated. It is expected that development of more potent and selective HIF inhibitors will provide an effective treatment of cancer and other HIF-related diseases, including inflammation and cardiovascular disorder. As VEGF plays an important role in angiogenesis during tumor growth and ischemic diseases, the inhibition of VEGF-induced HIF is an attractive approach for the suppression of hypoxia-mediated pathological angiogenesis. HIF inhibitors may not only have cytostatic antitumor effects with fewer side effects, but also synergetic effects combined with radiotherapy.

Novel and potent inhibitors of stearoyl-CoA desaturase-1. Part II: Identification of 4-ethylamino-3-(2-hydroxyethoxy)-N-[5-(3-trifluoromethylbenzyl)thiazol-2-yl]benzamide and its biological evaluation.

The continuing investigation of SAR studies of 3-(2-hydroxyethoxy)-N-(5-benzylthiazol-2-yl)-benzamides as stearoyl-CoA desaturase-1 (SCD-1) inhibitors is reported. Our prior hit-to-lead effort resulted in the identification of 1a as a potent and orally efficacious SCD-1 inhibitor. Further optimization of the structural motif resulted in the identification of 4-ethylamino-3-(2-hydroxyethoxy)-N-[5-(3-trifluoromethylbenzyl)thiazol-2-yl]benzamide (37c) with sub nano molar IC(50) in both murine and human SCD-1 inhibitory assays. This compound demonstrated a dose-dependent decrease in the plasma desaturation index in C57BL/6J mice on a non-fat diet after 7 days of oral administration.

Novel benzoylpiperidine-based stearoyl-CoA desaturase-1 inhibitors: Identification of 6-[4-(2-methylbenzoyl)piperidin-1-yl]pyridazine-3-carboxylic acid (2-hydroxy-2-pyridin-3-ylethyl)amide and its plasma triglyceride-lowering effects in Zucker fatty rats.

Starting from a known piperazine-based SCD-1 inhibitor, we obtained more potent benzoylpiperidine analogs. Optimization of the structure of the benzoylpiperidine-based SCD-1 inhibitors resulted in the identification of 6-[4-(2-methylbenzoyl)piperidin-1-yl]pyridazine-3-carboxylic acid (2-hydroxy-2-pyridin-3-yl-ethyl)amide (24) which showed strong inhibitory activity against both human and murine SCD-1. In addition, this compound exhibited good oral bioavailability and demonstrated plasma triglyceride lowering effects in Zucker fatty rats in a dose-dependent manner after a 7-day oral administration (qd).

Novel and potent inhibitors of stearoyl-CoA desaturase-1. Part I: Discovery of 3-(2-hydroxyethoxy)-4-methoxy-N-[5-(3-trifluoromethylbenzyl)thiazol-2-yl]benzamide

A series of structurally novel stearoyl-CoA desaturase-1 (SCD-1) inhibitors has been identified by optimizing a hit from our corporate library. Preliminary structure-activity relationship (SAR) studies led to the discovery of the highly potent and orally bioavailable thiazole-based SCD-1 inhibitor, 3-(2-hydroxyethoxy)-4-methoxy-N-[5-(3-trifluoromethylbenzyl)thiazol-2-yl]benzamide (23a).

Hypoxia-inducible factor (HIF) inhibitors: a patent survey (2011-2015)

ABSTRACT Introduction: Hypoxia-inducible factor (HIF)-1α regulates the expression of genes involved in angiogenesis, cellular energy metabolism, and cell survival during cancer development. The increased expression of HIF-1α in most solid tumors is associated with poor prognoses and therapeutic outcomes. Therefore, HIF has been recognized as an attractive target for cancer therapy, and many HIF inhibitors have been reported. Areas covered: This patent survey summarizes the information about patented HIF inhibitors over the last 5 years (2011–2015). Expert opinion: Although many of the HIF inhibitors reviewed in this patent survey possess inhibitory activity against cancer and HIF-related diseases, the compounds are still in the early stages of development, most likely due to the complexity of the HIF-1 pathway and their different mechanisms of action for HIF inhibition. Most cancer cells use the glycolytic pathway for energy production and HIF-1α participates deeply in the expression of several glycolytic enzymes. Therefore, a detailed study of HIF’s function in cancer metabolisms may provide us an alternative strategy for further development of HIF inhibitors in cancer therapy.

Recent progress in the discovery and development of stearoyl CoA desaturase inhibitors

Stearoyl-CoA desaturase 1 (SCD1) is a rate-limiting enzyme in the biosynthesis of monounsaturated fatty acids from their saturated fatty acid precursors. SCD1 introduces a cis-double bond at the Δ9 position (between carbons 9 and 10) of stearoyl (C18:0) and palmitoyl-CoA (C16:0). SCD1 has been shown to be a crucial factor in lipid metabolism and body weight control. In addition, SCD1 inhibitors are claimed to be new treatments for various diseases, such as skin disorders, nonalcoholic steatohepatitis (NASH), hepatitis C virus (HCV), Alzheimers disease, or cancer. This review aims to summarize the examples of the recently reported novel SCD1 inhibitors and to highlight the emerging areas of target indications that may hold promise for the development of SCD1 inhibitors.

1,2-Benzisoxazole compounds: a patent review (2009 – 2014)

Introduction: Benzisoxazoles represent a class of heterocyclic compounds of great importance for the preparation of biologically active compounds. Benzisoxazoles are an important structure and some benzisoxazole-based medicines have been approved for human clinical use, including atypical antipsychotics (risperidone, paliperidone and iloperidone) and an anticonvulsant (zonisamide). Areas covered: This review puts emphasis on the recent progress in therapeutically attractive benzisoxazole derivatives especially 1,2-benzisoxazoles, which were published in the patent literature between 2009 and 2014. As for the class of medicines, the main focus is on atypical antipsychotics and potential therapeutic treatments for other CNS disorders. This review also covers the examples of benzisoxazole-based kinase inhibitors. Moreover, novel benzisoxazoles with significant therapeutic interest are also mentioned. Expert opinion: More recent examples of structural modification of existing drugs led to the discovery of some promising benzisoxazoles for antipsychotic use. The design of multi-target ligands is important for the manipulation of pharmacological properties and safety profiles for the use of antipsychotics. Benzisoxazoles have been widely used as pharmacophores in the search for novel drug candidates in a variety of therapeutic area. It is fair to assume that the wide and frequent use of benzisoxazoles in drug discovery and development will continue into the future.

Piperidine and pyrrolidine analogs as glycogen synthase activators; a patent evaluation (WO2011058122)

A small series of piperidine analogs that effectively activate glycogen synthase (GS) was prepared in WO2011058122. The treatment or prophylaxis of metabolic disease and disorders by these novel GS activators is claimed. These compounds represent further variations around a structural motif explored in the prior patent publications by Roche.

Imidazo[1,2-a]pyridines as cholesterol 24-hydroxylase (CYP46A1) inhibitors: a patent evaluation (WO2014061676)

A series of imidazo[1,2-a]pyridine analogs that effectively inhibit cholesterol 24-hydroxylase (CYP46A1) was reported in WO2014061676. The treatment or prophylaxis of neurodegenerative disorders, such as Alzheimer’s disease and Parkinson’s disease, by these novel CYP46A1 inhibitors is claimed in the patent. These compounds represent a novel pharmacophore that is different from other structural motifs described in the prior patent publications by Takeda Pharmaceutical Company Ltd.

Benzisoxazole analogs as glycogen synthase activators, a patent evaluation (WO2011057956)

A small series of benzisoxazole analogs that effectively activate glycogen synthase (GS) was prepared in WO2011057956. These novel GS activators are claimed to be beneficial for the treatment or prophylaxis of metabolic disease and disorders. The 1,2-benzisoxazole-3-ol moiety is utilized in the present patent as a bioisoster of benzoic acid, which has often been employed in prior examples of the GS activators.