Glucokinase target for type 2 diabetes
Larry H. Bernstein, MD, FCAP, Curator
LPBI
Pfizer’s PF 04991532 a Hepatoselective Glucokinase Activator Clinical Candidate for Treating Type 2 Diabetes Mellitus
DR ANTHONY MELVIN CRASTO, WORLD DRUG TRACKER
http://newdrugapprovals.org/2015/11/27/pfizers-pf-04991532-a-hepatoselective-glucokinase-activator-clinical-candidate-for-treating-type-2-diabetes-mellitus/
PF 04991532
GKA PF-04991532
(S)-6-{3-cyclopentyl-2-[4-(trifluoromethyl)-1H-imidazol-1-yl]propanamido}nicotinic acid
(S)-6-(3-Cyclopentyl-2-(4-(trifluoromethyl)-1H-imidazol-1-yl)propanamido)nicotinic Acid
(S)-6-(3-cyclopentyl-2-(4-(trifluoromethyl)-1H-imidazol-1-yl)propanamido)nicotinic acid
MW 396.36, MF C18 H19 F3 N4 O3
CAS 1215197-37-7
3-Pyridinecarboxylic acid, 6-[[(2S)-3-cyclopentyl-1-oxo-2-[4-(trifluoromethyl)-1H-imidazol-1-yl]propyl]amino]-
http://www.biochemj.org/content/441/3/881
Type 2 diabetes mellitus (T2DM) is a rapidly expanding public epidemic affecting over 300 million people worldwide. This disease is characterized by elevated fasting plasma glucose (FPG), insulin resistance, abnormally elevated hepatic glucose production (HGP), and reduced glucose-stimulated insulin secretion (GSIS). Moreover, long-term lack of glycemic control increases risk of complications from neuropathic, microvascular, and macrovascular diseases.
The standard of care for T2DM is metformin followed by sulfonylureas, dipeptidyl peptidase-4 (DPP-IV) inhibitors, and thiazolidinediones (TZD) as second line oral therapies. As disease progression continues, patients typically require injectable agents such as glucagon-like peptide-1 (GLP-1) analogues and, ultimately, insulin to help maintain glycemic control. Despite these current therapies, many patients still remain unable to safely achieve and maintain tight glycemic control, placing them at risk of diabetic complications and highlighting the need for novel therapeutic options.
Glucokinase (hexokinase IV) continues to be a compelling target for the treatment of type 2 diabetes given the wealth of supporting human genetics data and numerous reports of robust clinical glucose lowering in patients treated with small molecule allosteric activators. Recent work has demonstrated the ability of hepatoselective activators to deliver glucose lowering efficacy with minimal risk of hypoglycemia.
While orally administered agents require a considerable degree of passive permeability to promote suitable exposures, there is no such restriction on intravenously delivered drugs. Therefore, minimization of membrane diffusion in the context of an intravenously agent should ensure optimal hepatic targeting and therapeutic index.
Diabetes is a major public health concern because of its increasing prevalence and associated health risks. The disease is characterized by metabolic defects in the production and utilization of carbohydrates which result in the failure to maintain appropriate blood glucose levels. Two major forms of diabetes are recognized. Type I diabetes, or insulin-dependent diabetes mellitus (IDDM), is the result of an absolute deficiency of insulin. Type II diabetes, or non-insulin dependent diabetes mellitus (NIDDM), often occurs with normal, or even elevated levels of insulin and appears to be the result of the inability of tissues and cells to respond appropriately to insulin. Aggressive control of NIDDM with medication is essential; otherwise it can progress into IDDM.
As blood glucose increases, it is transported into pancreatic beta cells via a glucose transporter. Intracellular mammalian glucokinase (GK) senses the rise in glucose and activates cellular glycolysis, i.e. the conversion of glucose to glucose-6-phosphate, and subsequent insulin release. Glucokinase is found principally in pancreatic β-cells and liver parenchymal cells. Because transfer of glucose from the blood into muscle and fatty tissue is insulin dependent, diabetics lack the ability to utilize glucose adequately which leads to undesired accumulation of blood glucose (hyperglycemia). Chronic hyperglycemia leads to decreases in insulin secretion and contributes to increased insulin resistance. Glucokinase also acts as a sensor in hepatic parenchymal cells which induces glycogen synthesis, thus preventing the release of glucose into the blood. The GK processes are thus critical for the maintenance of whole body glucose homeostasis.
It is expected that an agent that activates cellular GK will facilitate glucose-dependent secretion from pancreatic beta cells, correct postprandial hyperglycemia, increase hepatic glucose utilization and potentially inhibit hepatic glucose release. Consequently, a GK activator may provide therapeutic treatment for NIDDM and associated complications, inter alia, hyperglycemia, dyslipidemia, insulin resistance syndrome, hyperinsulinemia, hypertension, and obesity.
Several drugs in five major categories, each acting by different mechanisms, are available for treating hyperglycemia and subsequently, NIDDM (Moller, D. E., “New drug targets for Type II diabetes and the metabolic syndrome” Nature414; 821-827, (2001)): (A) Insulin secretogogues, including sulphonyl-ureas (e.g., glipizide, glimepiride, glyburide) and meglitinides (e.g., nateglidine and repaglinide) enhance secretion of insulin by acting on the pancreatic beta-cells. While this therapy can decrease blood glucose level, it has limited efficacy and tolerability, causes weight gain and often induces hypoglycemia. (B) Biguanides (e.g., metformin) are thought to act primarily by decreasing hepatic glucose production. Biguanides often cause gastrointestinal disturbances and lactic acidosis, further limiting their use. (C) Inhibitors of alpha-glucosidase (e.g., acarbose) decrease intestinal glucose absorption. These agents often cause gastrointestinal disturbances. (D) Thiazolidinediones (e.g., pioglitazone, rosiglitazone) act on a specific receptor (peroxisome proliferator-activated receptor-gamma) in the liver, muscle and fat tissues. They regulate lipid metabolism subsequently enhancing the response of these tissues to the actions of insulin. Frequent use of these drugs may lead to weight gain and may induce edema and anemia. (E) Insulin is used in more severe cases, either alone or in combination with the above agents.
Ideally, an effective new treatment for NIDDM would meet the following criteria: (a) it would not have significant side effects including induction of hypoglycemia; (b) it would not cause weight gain; (c) it would at least partially replace insulin by acting via mechanism(s) that are independent from the actions of insulin; (d) it would desirably be metabolically stable to allow less frequent usage; and (e) it would be usable in combination with tolerable amounts of any of the categories of drugs listed herein.
Substituted heteroaryls, particularly pyridones, have been implicated in mediating GK and may play a significant role in the treatment of NIDDM. For example, U.S. Patent publication No. 2006/0058353 and PCT publication Nos. WO2007/043638, WO2007/043638, and WO2007/117995 recite certain heterocyclic derivatives with utility for the treatment of diabetes. Although investigations are on-going, there still exists a need for a more effective and safe therapeutic treatment for diabetes, particularly NIDDM.
PATENT
US 20100063063
http://www.google.com/patents/US20100063063
SYNTHESIS CONSTRUCTION
6-aminonicotinic acid
BENZYL BROMIDE
FIRST KEY INTERMEDIATE
SECOND SERIES FOR NEXT INTERMEDIATE
CONDENSED WITH
4-Trifluoromethyl-1H-imidazole
TO GIVE PRODUCT SHOWN BELOW
(S)-methyl 3-cyclopentyl-2-(4-(trifluoromethyl)-1H-imidazol-1-yl)propanoate (I-8a)
CONVERTED TO ACID CHLORIDE, (S)-3-cyclopentyl-2-(4-(trifluoromethyl)-1H-imidazol-1-yl)propanoyl chloride (I-8c)
AND CONDENSED WITH
WILL GIVE BENZYL DERIVATIVE
THEN DEBENZYLATION TO FINAL PRODUCT
1H NMR (400 MHz, DMSO-d6) δ 13.10-13.25 (1H), 11.44 (1H), 8.83 (1H), 8.23-8.26 (1H), 8.09-8.12 (1H), 7.94-7.95 (2H), 5.22-5.26 (1H), 2.06-2.17 (2H), 1.29-1.64 (8H), 1.04-1.07 (1H); m/z 397.3 (M+H)+.
Organic Process Research & Development (2012), 16(10), 1635-1645
http://pubs.acs.org/doi/abs/10.1021/op300194c

This work describes the process development and manufacture of early-stage clinical supplies of a hepatoselective glucokinase activator, a potential therapy for type 2 diabetes mellitus. Critical issues centered on challenges associated with the synthesis of intermediates and API bearing a particularly racemization-prone α-aryl carboxylate functionality. In particular, a T3P-mediated amidation process was optimized for the coupling of a racemization-prone acid substrate and a relatively non-nucleophilic amine. Furthermore, an unusually hydrolytically-labile amide in the API also complicated the synthesis and isolation of drug substance. The evolution of the process over multiple campaigns is presented, resulting in the preparation of over 110 kg of glucokinase activator.
(S)-6-(3-Cyclopentyl-2-(4-(trifluoromethyl)-1H-imidazol-1-yl)propanamido)nicotinic Acid (1)
Journal of Medicinal Chemistry (2012), 55(3), 1318-1333
http://pubs.acs.org/doi/abs/10.1021/jm2014887

Glucokinase is a key regulator of glucose homeostasis, and small molecule allosteric activators of this enzyme represent a promising opportunity for the treatment of type 2 diabetes. Systemically acting glucokinase activators (liver and pancreas) have been reported to be efficacious but in many cases present hypoglycaemia risk due to activation of the enzyme at low glucose levels in the pancreas, leading to inappropriately excessive insulin secretion. It was therefore postulated that a liver selective activator may offer effective glycemic control with reduced hypoglycemia risk. Herein, we report structure–activity studies on a carboxylic acid containing series of glucokinase activators with preferential activity in hepatocytes versus pancreatic β-cells. These activators were designed to have low passive permeability thereby minimizing distribution into extrahepatic tissues; concurrently, they were also optimized as substrates for active liver uptake via members of the organic anion transporting polypeptide (OATP) family. These studies lead to the identification of 19 as a potent glucokinase activator with a greater than 50-fold liver-to-pancreas ratio of tissue distribution in rodent and non-rodent species. In preclinical diabetic animals, 19 was found to robustly lower fasting and postprandial glucose with no hypoglycemia, leading to its selection as a clinical development candidate for treating type 2 diabetes.
Bioorganic & Medicinal Chemistry Letters (2013), 23(24), 6588-6592
http://www.sciencedirect.com/science/article/pii/S0960894X13012638
Figure 1.
Structure of Hepatoselective GKA PF-04991532 (1).
Pfizer’s PF 04937319 glucokinase activators for the treatment of Type 2 diabetes
DR ANTHONY MELVIN CRASTO, WORLD DRUG TRACKER
http://newdrugapprovals.org/2015/11/27/pfizers-pf-04937319-glucokinase-activators-for-the-treatment-of-type-2-diabetes/
PF 04937319
N,N-dimethyl-5-(2-methyl-6-((5-methylpyrazin-2-yl)-carbamoyl)benzofuran-4-yloxy)pyrimidine-2-carboxamide
MW 432.43
A trial to assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of single doses of PF-04937319 in subjects with type 2 diabetes mellitus (NCT01044537)
SYNTHESIS
Glucokinase is a key regulator of glucose homeostasis and small molecule activators of this enzyme represent a promising opportunity for the treatment of Type 2 diabetes. Several glucokinase activators have advanced to clinical studies and demonstrated promising efficacy; however, many of these early candidates also revealed hypoglycemia as a key risk. In an effort to mitigate this hypoglycemia risk while maintaining the promising efficacy of this mechanism, we have investigated a series of substituted 2-methylbenzofurans as “partial activators” of the glucokinase enzyme leading to the identification ofN,N-dimethyl-5-(2-methyl-6-((5-methylpyrazin-2-yl)-carbamoyl)benzofuran-4-yloxy)pyrimidine-2-carboxamide as an early development candidate.
It is expected that an agent that activates cellular GK will facilitate glucose-dependent secretion from pancreatic beta cells, correct postprandial hyperglycemia, increase hepatic glucose utilization and potentially inhibit hepatic glucose release. Consequently, a GK activator may provide therapeutic treatment for NIDDM and associated complications, inter alia, hyperglycemia, dyslipidemia, insulin resistance syndrome, hyperinsulinemia, hypertension, and obesity. Several drugs in five major categories, each acting by different mechanisms, are available for treating hyperglycemia and subsequently, NIDDM (Moller, D. E., “New drug targets for Type 2 diabetes and the metabolic syndrome” Nature 414; 821 -827, (2001 )): (A) Insulin secretogogues, including sulphonyl-ureas (e.g., glipizide, glimepiride, glyburide) and meglitinides (e.g., nateglidine and repaglinide) enhance secretion of insulin by acting on the pancreatic beta-cells. While this therapy can decrease blood glucose level, it has limited efficacy and tolerability, causes weight gain and often induces hypoglycemia. (B) Biguanides (e.g., metformin) are thought to act primarily by decreasing hepatic glucose production. Biguanides often cause gastrointestinal disturbances and lactic acidosis, further limiting their use. (C) Inhibitors of alpha-glucosidase (e.g., acarbose) decrease intestinal glucose absorption. These agents often cause gastrointestinal disturbances. (D) Thiazolidinediones (e.g., pioglitazone, rosiglitazone) act on a specific receptor (peroxisome proliferator-activated receptor-gamma) in the liver, muscle and fat tissues. They regulate lipid metabolism subsequently enhancing the response of these tissues to the actions of insulin. Frequent use of these drugs may lead to weight gain and may induce edema and anemia. (E) Insulin is used in more severe cases, either alone or in combination with the above agents. Ideally, an effective new treatment for NIDDM would meet the following criteria: (a) it would not have significant side effects including induction of hypoglycemia; (b) it would not cause weight gain; (c) it would at least partially replace insulin by acting via mechanism(s) that are independent from the actions of insulin; (d) it would desirably be metabolically stable to allow less frequent usage; and (e) it would be usable in combination with tolerable amounts of any of the categories of drugs listed herein.
Substituted heteroaryls, particularly pyridones, have been implicated in mediating GK and may play a significant role in the treatment of NIDDM. For example, U.S. Patent publication No. 2006/0058353 and PCT publication No’s. WO2007/043638, WO2007/043638, and WO2007/117995 recite certain heterocyclic derivatives with utility for the treatment of diabetes. Although investigations are on-going, there still exists a need for a more effective and safe therapeutic treatment for diabetes, particularly NIDDM.
Designing glucokinase activators with reduced hypoglycemia risk: discovery of N,N-dimethyl-5-(2-methyl-6-((5-methylpyrazin-2-yl)-carbamoyl)benzofuran-4-yloxy)pyrimidine-2-carboxamide as a clinical candidate for the treatment of type 2 diabetes mellitus
E-mail: jeffrey.a.pfefferkorn@pfizer.com
Tel: +860 686 3421
DOI: 10.1039/C1MD00116G
http://pubs.rsc.org/en/content/articlelanding/2011/md/c1md00116g/unauth#!divAbstract
http://www.rsc.org/suppdata/md/c1/c1md00116g/c1md00116g.pdf
N,N-Dimethyl-5-(2-methyl-6-((5-methylpyrazin-2-yl)carbamoyl)-benzofuran-4- yloxy)pyrimidine-2-carboxamide (28).
PAPER
http://pubs.rsc.org/en/content/articlelanding/2013/md/c2md20317k#!divAbstract
PAPER
Bioorganic & Medicinal Chemistry Letters (2013), 23(16), 4571-4578
http://www.sciencedirect.com/science/article/pii/S0960894X13007452
Figure 1.
Glucokinase activators 1 and 2.
PATENT
WO 2010103437
https://www.google.co.in/patents/WO2010103437A1?cl=en
Scheme I outlines the general procedures one could use to provide compounds of the present invention having Formula (I).

Preparations of Starting Materials and Key Intermediates
Beebe, D.A.; Ross, T.T.; Rolph, T.P.; Pfefferkorn, J.A.; Esler, W.P.
The glucokinase activator PF-04937319 improves glycemic control in combination with exercise without causing hypoglycemia in diabetic rats
74th Annu Meet Sci Sess Am Diabetes Assoc (ADA) (June 13-17, San Francisco) 2014, Abst 1113-P
Amin, N.B.; Aggarwal, N.; Pall, D.; Paragh, G.; Denney, W.S.; Le, V.; Riggs, M.; Calle, R.A.
Two dose-ranging studies with PF-04937319, a systemic partial activator of glucokinase, as add-on therapy to metformin in adults with type 2 diabetes
Diabetes Obes Metab 2015, 17(8): 751
Study to compare single dose of three modified release formulations of PF-04937319 with immediate release material-sparing-tablet (IR MST) formulation previously studied in adults with type 2 diabetes mellitus (NCT02206607)
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