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The glucokinase-glucokinase regulatory protein (GK-GKRP) complex plays an important role in controlling glucose homeostasis in the liver. We have recently disclosed a series of arylpiperazines as in vitro and in vivo disruptors of the GK-GKRP complex with efficacy in rodent models of type 2 diabetes mellitus (T2DM). Herein, we describe a new class of aryl sulfones as disruptors of the GK-GKRP complex, where the central piperazine scaffold has been replaced by an aromatic group. Conformational analysis and exploration of the structure-activity relationships of this new class of compounds led to the identification of potent GK-GKRP disruptors. Further optimization of this novel series delivered thiazole sulfone 93, which was able to disrupt the GK-GKRP interaction in vitro and in vivo and, by doing so, increases cytoplasmic levels of unbound GK.

Small molecule activators of glucokinase have shown robust efficacy in both preclinical models and humans. However, overactivation of glucokinase (GK) can cause excessive glucose turnover, leading to hypoglycemia. To circumvent this adverse side effect, we chose to modulate GK activity by targeting the endogenous inhibitor of GK, glucokinase regulatory protein (GKRP). Disrupting the GK-GKRP complex results in an increase in the amount of unbound cytosolic GK without altering the inherent kinetics of the enzyme. Herein we report the identification of compounds that efficiently disrupt the GK-GKRP interaction via a previously unknown binding pocket. Using a structure-based approach, the potency of the initial hit was improved to provide 25 (AMG-1694). When dosed in ZDF rats, 25 showed both a robust pharmacodynamic effect as well as a statistically significant reduction in glucose. Additionally, hypoglycemia was not observed in either the hyperglycemic or normal rats.

11Beta-hydroxysteroid dehydrogenase type 1 regulates glucocorticoid action and inhibition of this enzyme is a viable therapeutic strategy for the treatment of type 2 diabetes and the metabolic syndrome. Here, we report a potent and selective 11beta-hydroxysteroid dehydrogenase type 1 inhibitor with a binding mode elucidated from the co-crystal structure with the human 11beta-hydroxysteroid dehydrogenase type 1. The inhibitor is bound to the steroid-binding pocket making contacts with the catalytic center and the solvent channel. The inhibitor binding is facilitated by two direct hydrogen bond interactions involving Tyrosine183 of the catalytic motif Tyr-X-X-X-Lys and Alanine172. In addition, the inhibitor makes many hydrophobic interactions with both the enzyme and the co-factor nicotinamide adenine dinucleotide phosphate (reduced). In lean C57BL/6 mice, the compound inhibited both the in vivo and ex vivo 11beta-hydroxysteroid dehydrogenase type 1 activities in a dose-dependent manner. The inhibitory effects correlate with the plasma compound concentrations, suggesting that there is a clear pharmacokinetic and pharmacodynamic relationship. Moreover, at the same doses used in the pharmacokinetic/pharmacodynamic studies, the inhibitor did not cause the activation of the hypothalamic-pituitary-adrenal axis in an acute mouse model, suggesting that this compound exhibits biological effects with minimal risk of activating the hypothalamic-pituitary-adrenal axis.

A series of 2-anilinothiazolones were prepared as inhibitors of 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1). The most potent compounds contained a 2-chloro or 2-fluoro group on the aniline ring with an isopropyl substituent on the 5-position of the thiazolone ring (compounds 2 and 3, respectively). The binding mode was determined through the X-ray co-crystal structure of the enzyme with compound 3. This compound was also approximately 70-fold selective over 11beta-HSD2 and was orally bioavailable in rat pharmacokinetic studies. However, compound 3 was >580-fold less active in the 11beta-HSD1 cell assay when tested in the presence of 3% human serum albumin.

We have recently reported a novel approach to increase cytosolic glucokinase (GK) levels through the binding of a small molecule to its endogenous inhibitor, glucokinase regulatory protein (GKRP). These initial investigations culminated in the identification of 2-(4-((2S)-4-((6-amino-3-pyridinyl)sulfonyl)-2-(1-propyn-1-yl)-1-piperazinyl)phenyl)-1,1,1,3,3,3-hexafluoro-2-propanol (1, AMG-3969), a compound that effectively enhanced GK translocation and reduced blood glucose levels in diabetic animals. Herein we report the results of our expanded SAR investigations that focused on modifications to the aryl carbinol group of this series. Guided by the X-ray cocrystal structure of compound 1 bound to hGKRP, we identified several potent GK-GKRP disruptors bearing a diverse set of functionalities in the aryl carbinol region. Among them, sulfoximine and pyridinyl derivatives 24 and 29 possessed excellent potency as well as favorable PK properties. When dosed orally in db/db mice, both compounds significantly lowered fed blood glucose levels (up to 58%).

In the previous report , we described the discovery and optimization of novel small molecule disruptors of the GK-GKRP interaction culminating in the identification of 1 (AMG-1694). Although this analogue possessed excellent in vitro potency and was a useful tool compound in initial proof-of-concept experiments, high metabolic turnover limited its advancement. Guided by a combination of metabolite identification and structure-based design, we have successfully discovered a potent and metabolically stable GK-GKRP disruptor (27, AMG-3969). When administered to db/db mice, this compound demonstrated a robust pharmacodynamic response (GK translocation) as well as statistically significant dose-dependent reductions in fed blood glucose levels.

Proteins of the tissue inhibitor of metalloproteinase (TIMP) family bind and inactivate matrix metalloproteinases such as collagenases and gelatinases. We report the cloning and sequencing of cDNAs encoding a novel human TIMP, which we designated TIMP-3, the third member of the human TIMP family. Degenerate PCR primers derived from highly conserved regions of TIMP family cDNAs amplified a 402-bp product from human fetal kidney cDNA. This product and a related 333-bp PCR product were used as probes to screen two cDNA libraries. Three TIMP-3 cDNA clones were isolated, including a 1240-bp fetal kidney clone that contained a complete TIMP-3 precursor coding region of 211 amino acids (aa). The deduced precursor protein includes twelve Cys and 27 other aa that are invariant in the TIMP family. The predicted aa sequence is 89, 39 and 46% identical to those of ChIMP-3, human TIMP-1 and human TIMP-2, respectively. Northern blot analyses detected three TIMP-3 mRNA bands of 2.2, 2.5 and 4.4 kb in several human cell lines.

The insulin-like growth factor-1 receptor (IGF-1R) plays an important role in the regulation of cell growth and differentiation, and in protection from apoptosis. IGF-1R has been shown to be an appealing target for the treatment of human cancer. Herein, we report the synthesis, structure-activity relationships (SAR), X-ray cocrystal structure and in vivo tumor study results for a series of 2,4-bis-arylamino-1,3-pyrimidines.

A series of compounds containing the 2-amino-1,3-thiazol-4(5H)-one core were found to be potent inhibitors of the enzyme 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1). One of our lead compounds from this series activated the human nuclear xenobiotic receptor, pregnane X receptor (PXR). To try and mitigate the PXR activity, we prepared analogues of our lead series that contained polar groups on the right-hand side of the thiazolone. Several analogues containing amides or alcohols appended to the C-5 position of the thiazolone showed a significant reduction in PXR activity. Through these structure-activity efforts, a compound containing a tert-alcohol group off the C-5 position, analogue (S)-33a, was found to have an 11beta-HSD1 Ki = 35 nM and negligible PXR activity. Compound (S)-33a was advanced into a pharmacodynamic model in cynomolgus monkeys, where it inhibited adipose 11beta-HSD1 activity after being orally administered.

11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) is the enzyme that converts cortisone to cortisol. A growing body of evidence suggests that selective inhibition of 11beta-HSD1 could potentially treat metabolic syndrome as well as type 2 diabetes. Through modification of our initial lead 1, we have discovered trifluoromethyl thiazolone 17. This compound had a Ki of 22 nM, possessed low in vivo clearance, and showed a 91% inhibition of adipose 11beta-HSD1 enzymatic activity in a mouse ex vivo pharmacodynamic model.