Showing papers in "Journal of Medicinal Chemistry in 2015"
TL;DR: The effects of the strategic incorporation of fluorine in drug molecules and applications in positron emission tomography are provided, as well as new synthetic methodologies that allow more facile access to a wide range of fluorinated compounds.
Abstract: The role of fluorine in drug design and development is expanding rapidly as we learn more about the unique properties associated with this unusual element and how to deploy it with greater sophistication. The judicious introduction of fluorine into a molecule can productively influence conformation, pKa, intrinsic potency, membrane permeability, metabolic pathways, and pharmacokinetic properties. In addition, 18F has been established as a useful positron emitting isotope for use with in vivo imaging technology that potentially has extensive application in drug discovery and development, often limited only by convenient synthetic accessibility to labeled compounds. The wide ranging applications of fluorine in drug design are providing a strong stimulus for the development of new synthetic methodologies that allow more facile access to a wide range of fluorinated compounds. In this review, we provide an update on the effects of the strategic incorporation of fluorine in drug molecules and applications in po...
2,149 citations
TL;DR: A novel approach (pkCSM) which uses graph-based signatures to develop predictive models of central ADMET properties for drug development and performs as well or better than current methods.
Abstract: Drug development has a high attrition rate, with poor pharmacokinetic and safety properties a significant hurdle. Computational approaches may help minimize these risks. We have developed a novel approach (pkCSM) which uses graph-based signatures to develop predictive models of central ADMET properties for drug development. pkCSM performs as well or better than current methods. A freely accessible web server (http://structure.bioc.cam.ac.uk/pkcsm), which retains no information submitted to it, provides an integrated platform to rapidly evaluate pharmacokinetic and toxicity properties.
1,866 citations
TL;DR: The fatty acid moiety and the linking chemistry to GLp-1 were the key features to secure high albumin affinity and GLP-1 receptor (GLP- 1R) potency and in obtaining a prolonged exposure and action of the GLP -1 analogue.
Abstract: Liraglutide is an acylated glucagon-like peptide-1 (GLP-1) analogue that binds to serum albumin in vivo and is approved for once-daily treatment of diabetes as well as obesity. The aim of the present studies was to design a once weekly GLP-1 analogue by increasing albumin affinity and secure full stability against metabolic degradation. The fatty acid moiety and the linking chemistry to GLP-1 were the key features to secure high albumin affinity and GLP-1 receptor (GLP-1R) potency and in obtaining a prolonged exposure and action of the GLP-1 analogue. Semaglutide was selected as the optimal once weekly candidate. Semaglutide has two amino acid substitutions compared to human GLP-1 (Aib8, Arg34) and is derivatized at lysine 26. The GLP-1R affinity of semaglutide (0.38 ± 0.06 nM) was three-fold decreased compared to liraglutide, whereas the albumin affinity was increased. The plasma half-life was 46.1 h in mini-pigs following i.v. administration, and semaglutide has an MRT of 63.6 h after s.c. dosing to min...
524 citations
TL;DR: The role of sulfur interactions in protein structure and function is discussed and although relatively rare, intermolecular interactions between ligand C-S σ* orbitals and proteins are illustrated.
Abstract: Electron deficient, bivalent sulfur atoms have two areas of positive electrostatic potential, a consequence of the low-lying σ* orbitals of the C–S bond that are available for interaction with electron donors including oxygen and nitrogen atoms and, possibly, π-systems. Intramolecular interactions are by far the most common manifestation of this effect, which offers a means of modulating the conformational preferences of a molecule. Although a well-documented phenomenon, a priori applications in drug design are relatively sparse and this interaction, which is often isosteric with an intramolecular hydrogen-bonding interaction, appears to be underappreciated by the medicinal chemistry community. In this Perspective, we discuss the theoretical basis for sulfur σ* orbital interactions and illustrate their importance in the context of drug design and organic synthesis. The role of sulfur interactions in protein structure and function is discussed and although relatively rare, intermolecular interactions betwe...
514 citations
TL;DR: In this article, the authors present properties and stabilities of carbamates, reagents and chemical methodologies for the synthesis of caramates and their applications in drug design and medicinal chemistry.
Abstract: The carbamate group is a key structural motif in many approved drugs and prodrugs. There is an increasing use of carbamates in medicinal chemistry and many derivatives are specifically designed to make drug–target interactions through their carbamate moiety. In this Perspective, we present properties and stabilities of carbamates, reagents and chemical methodologies for the synthesis of carbamates, and recent applications of carbamates in drug design and medicinal chemistry.
447 citations
TL;DR: A review of the design, synthesis, properties, preclinical, and clinical studies of seven clinical-stage MDM2 inhibitors for the treatment of human cancers.
Abstract: Design of small-molecule inhibitors (MDM2 inhibitors) to block the MDM2–p53 protein–protein interaction has been pursued as a new cancer therapeutic strategy. In recent years, potent, selective, and efficacious MDM2 inhibitors have been successfully obtained and seven such compounds have been advanced into early phase clinical trials for the treatment of human cancers. Here, we review the design, synthesis, properties, preclinical, and clinical studies of these clinical-stage MDM2 inhibitors.
401 citations
TL;DR: A particular emphasis is placed on the interplay between the most critical physicochemical and pharmacokinetic parameters of CNS drugs as well as their impact on medicinal chemistry strategies toward molecules with optimal brain exposure.
Abstract: The human brain is a uniquely complex organ, which has evolved a sophisticated protection system to prevent injury from external insults and toxins. Designing molecules that can overcome this protection system and achieve optimal concentration at the desired therapeutic target in the brain is a specific and major challenge for medicinal chemists working in CNS drug discovery. Analogous to the now widely accepted rule of 5 in the design of oral drugs, the physicochemical properties required for optimal brain exposure have been extensively studied in an attempt to similarly define the attributes of successful CNS drugs and drug candidates. This body of work is systematically reviewed here, with a particular emphasis on the interplay between the most critical physicochemical and pharmacokinetic parameters of CNS drugs as well as their impact on medicinal chemistry strategies toward molecules with optimal brain exposure. A summary of modern CNS pharmacokinetic concepts and methods is also provided.
383 citations
TL;DR: The current status of research in the Na( v) field is summarized and the most relevant recent developments with respect to the molecular structure, general physiology, and pharmacology of distinct Na(v) channel subtypes are presented.
Abstract: The tremendous therapeutic potential of voltage-gated sodium channels (Na(v)s) has been the subject of many studies in the past and is of intense interest today. Na(v)1.7 channels in particular have received much attention recently because of strong genetic validation of their involvement in nociception. Here we summarize the current status of research in the Na(v) field and present the most relevant recent developments with respect to the molecular structure, general physiology, and pharmacology of distinct Na(v) channel subtypes. We discuss Na(v) channel ligands such as small molecules, toxins isolated from animal venoms, and the recently identified Na(v)1.7-selective antibody. Furthermore, we review eight characterized ligand binding sites on the Na(v) channel α subunit. Finally, we examine possible therapeutic applications of Na(v) ligands and provide an update on current clinical studies.
343 citations
TL;DR: Studies in vitro and in vivo show that RPX7009 (9f) is a broad-spectrum inhibitor, notably restoring the activity of carbapenems against KPC-producing strains, and 9f is a promising product for the treatment of multidrug resistant Gram-negative bacteria.
Abstract: The increasing dissemination of carbapenemases in Gram-negative bacteria has threatened the clinical usefulness of the β-lactam class of antimicrobials. A program was initiated to discover a new series of serine β-lactamase inhibitors containing a boronic acid pharmacophore, with the goal of finding a potent inhibitor of serine carbapenemase enzymes that are currently compromising the utility of the carbapenem class of antibacterials. Potential lead structures were screened in silico by modeling into the active sites of key serine β-lactamases. Promising candidate molecules were synthesized and evaluated in biochemical and whole-cell assays. Inhibitors were identified with potent inhibition of serine carbapenemases, particularly the Klebsiella pneumoniae carbapenemase (KPC), with no inhibition of mammalian serine proteases. Studies in vitro and in vivo show that RPX7009 (9f) is a broad-spectrum inhibitor, notably restoring the activity of carbapenems against KPC-producing strains. Combined with a carbapen...
328 citations
TL;DR: This study investigates an approach that uses lipophilicity, affinity, and similarity to known aggregators to advise on the likelihood that a candidate compound is an aggregator, and finds that 85% of the ligands acting in the 0.1 to 10 μM range in the medicinal chemistry literature are at least 85% similar to a known aggregator with these physical properties and may aggregate at relevant concentrations.
Abstract: Colloidal aggregation of organic molecules is the dominant mechanism for artifactual inhibition of proteins, and controls against it are widely deployed. Notwithstanding an increasingly detailed understanding of this phenomenon, a method to reliably predict aggregation has remained elusive. Correspondingly, active molecules that act via aggregation continue to be found in early discovery campaigns and remain common in the literature. Over the past decade, over 12 thousand aggregating organic molecules have been identified, potentially enabling a precedent-based approach to match known aggregators with new molecules that may be expected to aggregate and lead to artifacts. We investigate an approach that uses lipophilicity, affinity, and similarity to known aggregators to advise on the likelihood that a candidate compound is an aggregator. In prospective experimental testing, five of seven new molecules with Tanimoto coefficients (Tc’s) between 0.95 and 0.99 to known aggregators aggregated at relevant conce...
327 citations
TL;DR: The chemical basis for assay interference and promiscuous enzymatic inhibition for several prominent chemotypes identified by this HTS, including some pan-assay interference compounds (PAINS) are characterized and identified.
Abstract: Significant resources in early drug discovery are spent unknowingly pursuing artifacts and promiscuous bioactive compounds, while understanding the chemical basis for these adverse behaviors often goes unexplored in pursuit of lead compounds. Nearly all the hits from our recent sulfhydryl-scavenging high-throughput screen (HTS) targeting the histone acetyltransferase Rtt109 were such compounds. Herein, we characterize the chemical basis for assay interference and promiscuous enzymatic inhibition for several prominent chemotypes identified by this HTS, including some pan-assay interference compounds (PAINS). Protein mass spectrometry and ALARM NMR confirmed these compounds react covalently with cysteines on multiple proteins. Unfortunately, compounds containing these chemotypes have been published as screening actives in reputable journals and even touted as chemical probes or preclinical candidates. Our detailed characterization and identification of such thiol-reactive chemotypes should accelerate triage...
TL;DR: A comprehensive summary of the preclinical and clinical research and development of nintedanib from the initial drug discovery process to the latest available clinical trial data is provided.
Abstract: Nintedanib (BIBF1120) is a potent, oral, small-molecule tyrosine kinase inhibitor, also known as a triple angiokinase inhibitor, inhibiting three major signaling pathways involved in angiogenesis. Nintedanib targets proangiogenic and pro-fibrotic pathways mediated by the VEGFR family, the fibroblast growth factor receptor (FGFR) family, the platelet-derived growth factor receptor (PDGFR) family, as well as Src and Flt-3 kinases. The compound was identified during a lead optimization program for small-molecule inhibitors of angiogenesis and has since undergone extensive clinical investigation for the treatment of various solid tumors, and in patients with the debilitating lung disease idiopathic pulmonary fibrosis (IPF). Recent clinical evidence from phase III studies has shown that nintedanib has significant efficacy in the treatment of NSCLC, ovarian cancer, and IPF. This review article provides a comprehensive summary of the preclinical and clinical research and development of nintedanib from the initia...
TL;DR: The identification and characterization of a series of small-molecule, orally bioavailable SERDs which are potent antagonists and degraders of ER-α and in which the ER- α degrading properties were prospectively optimized are described.
Abstract: Approximately 80% of breast cancers are estrogen receptor alpha (ER-α) positive, and although women typically initially respond well to antihormonal therapies such as tamoxifen and aromatase inhibitors, resistance often emerges. Although a variety of resistance mechanism may be at play in this state, there is evidence that in many cases the ER still plays a central role, including mutations in the ER leading to constitutively active receptor. Fulvestrant is a steroid-based, selective estrogen receptor degrader (SERD) that both antagonizes and degrades ER-α and is active in patients who have progressed on antihormonal agents. However, fulvestrant suffers from poor pharmaceutical properties and must be administered by intramuscular injections that limit the total amount of drug that can be administered and hence lead to the potential for incomplete receptor blockade. We describe the identification and characterization of a series of small-molecule, orally bioavailable SERDs which are potent antagonists and ...
TL;DR: Issues in the employed experimental protocols, review and classify reported IDO1 inhibitors, and suggest different approaches for confirming viable inhibitor scaffolds are described.
Abstract: Since the discovery of indoleamine 2,3-dioxygenase 1 (IDO1) as an attractive target for anticancer therapy in 2003, the search for inhibitors has been intensely pursued both in academia and in pharmaceutical companies. Many novel IDO1 inhibitor scaffolds have been described, and a few potent compounds have entered clinical trials. However, a significant number of the reported compounds contain problematic functional groups, suggesting that enzyme inhibition could be the result of undesirable side reactions instead of selective binding to IDO1. Here, we describe issues in the employed experimental protocols, review and classify reported IDO1 inhibitors, and suggest different approaches for confirming viable inhibitor scaffolds.
TL;DR: All tested bromophenol derivatives exhibited excellent inhibitory effects, in the low nanomolar range, with Ki values in the range of 0.97-12.14 nM against hCA II, whereas they were low micromolar inhibitors against h CA IX and XII.
Abstract: Cyclopropylcarboxylic acids and esters and cyclopropylmethanols incorporating bromophenol moieties were investigated as inhibitors of the carbonic anhydrase enzyme (CA; EC 4.2.1.1). The cis- and trans-esters 5 and 6 were obtained from the reaction of 4-allyl-1,2-dimethoxybenzene (4) with ethyl diazoacetate, which after bromination with Br2 gave two isomeric monobromides (11 and 15), four isomeric dibromides (12, 13, 16, and 17), and two isomeric tribromides (14 and 18). The carboxylic acids 7, 8, and 19–26 were thereafter obtained by hydrolysis of the synthesized esters. All these bromophenol derivatives were tested against human (h) CA isoenzymes I and II (cytosolic, ubiquitous isoforms) and hCA IX and XII (transmembrane, tumor-associated enzymes). All tested bromophenols exhibited excellent inhibitory effects, in the low nanomolar range, with Ki values in the range of 0.54–59 nM against hCA I and in the range of 0.97–12.14 nM against hCA II, whereas they were low micromolar inhibitors against hCA IX and...
TL;DR: This review brings together all the available information from primary literature sources relating to both discoveries and provides for the first time a much fuller story of the earliest years of this important class of drugs.
Abstract: Published descriptions of the specific lines of research leading to the discovery of therapeutically important medicines, especially major new class medicines, have long provided value to the biopharmaceutical community as models of success, often influencing the strategies and methods of subsequent drug research. Quinolone antibacterials represent one of medicine’s most important classes of anti-infective agents; yet in contrast to many other classes of anti-infectives, astonishingly few details concerning the origin of the class or the rationale leading to the selection of the first clinical agent, nalidixic acid, were ever published by the discoverers. Moreover, earlier disclosures of an independent discovery of the quinolone class of antibacterials have been almost entirely overlooked by the scientific literature. This review brings together all the available information from primary literature sources relating to both discoveries and provides for the first time a much fuller, if still partially specu...
TL;DR: This drug annotation summarizes the mechanisms of action, scientific rationale, medicinal chemistry, pharmacokinetic properties, and human efficacy data for galeterone, which has successfully completed phase II clinical development in men with castration resistant (advanced) prostate cancer (CRPC).
Abstract: In our effort to discover potent and specific inhibitors of 17α-hydroxylase/17,20-lyase (CYP17), the key enzyme which catalyzes the biosynthesis of androgens from progestins, 3β-(hydroxy)-17-(1H-benzimidazole-1-yl)androsta-5,16-diene (Galeterone or TOK-001, formerly called VN/124-1) was identified as a selective development candidate which modulates multiple targets in the androgen receptor (AR) signaling pathway. This drug annotation summarizes the mechanisms of action, scientific rationale, medicinal chemistry, pharmacokinetic properties, and human efficacy data for galeterone, which has successfully completed phase II clinical development in men with castration resistant (advanced) prostate cancer (CRPC). Phase III clinical studies in CRPC patients are scheduled to begin in early 2015.
TL;DR: Despite considerable efforts in understanding the binding interaction with specific substrates or inhibitors, structural information available for the rational design of new hMAO-B inhibitors remains unsatisfactory and the quest for novel, potent, and selective h MAO- B inhibitors remains of high interest.
Abstract: Accumulating evidence shows a relationship between the human MAO-B (hMAO-B) enzyme and neuropsychiatric/degenerative disorder, personality traits, type II alcoholism, borderline personality disorders, aggressiveness and violence in crime, obsessive-compulsive disorder, depression, suicide, schizophrenia, anorexia nervosa, migraine, dementia, and PD. Thus, MAO-B represents an attractive target for the treatment of a number of human diseases. The discovery, development, and therapeutic use of drugs that inhibit MAO-B are major challenges for future therapy. Various compounds and drugs that selectively target this isoform have been discovered recently. These agents are synthetic compounds or natural products and their analogues, including chalcones, pyrazoles, chromones, coumarins, xanthines, isatin derivatives, thiazolidindiones, (thiazol-2-yl)hydrazones, and analogues of marketed drugs. Despite considerable efforts in understanding the binding interaction with specific substrates or inhibitors, structural information available for the rational design of new hMAO-B inhibitors remains unsatisfactory. Therefore, the quest for novel, potent, and selective hMAO-B inhibitors remains of high interest.
TL;DR: Although a design strategy against volume of distribution can be advantageous in achieving desirable dosing regimen, it must be well-directed in order to avoid detrimental effects to other important properties.
Abstract: Volume of distribution is one of the most important pharmacokinetic properties of a drug candidate. It is a major determinant of half-life and dosing frequency of a drug. For a similar log P, a basic molecule will tend to exhibit higher volume of distribution than a neutral molecule. Acids often exhibit low volumes of distribution. Although a design strategy against volume of distribution can be advantageous in achieving desirable dosing regimen, it must be well-directed in order to avoid detrimental effects to other important properties. Strategies to increase volume of distribution include adding lipophilicity and introducing basic functional groups in a way that does not increase metabolic clearance.
TL;DR: An achievement of multifunctional ALR2 inhibitors having both potency for aldose reductase inhibition and as antioxidants is suggested.
Abstract: Quinoxalin-2(1H)-one based design and synthesis produced several series of aldose reductase (ALR2) inhibitor candidates. In particular, phenolic structure was installed in the compounds for the combination of antioxidant activity and strengthening the ability to fight against diabetic complications. Most of the series 6 showed potent and selective effects on ALR2 inhibition with IC50 values in the range of 0.032–0.468 μM, and 2-(3-(2,4-dihydroxyphenyl)-7-fluoro-2-oxoquinoxalin-1(2H)-yl)acetic acid (6e) was the most active. More significantly, most of the series 8 revealed not only good activity in the ALR2 inhibition but also potent antioxidant activity, and 2-(3-(3-methoxy-4-hydroxystyryl)-2-oxoquinoxalin-1(2H)-yl)acetic acid (8d) was even as strong as the well-known antioxidant Trolox at a concentration of 100 μM, verifying the C3 p-hydroxystyryl side chain as the key structure for alleviating oxidative stress. These results therefore suggest an achievement of multifunctional ALR2 inhibitors having both...
TL;DR: The synthesis of a collection of 3-substituted indole derivatives incorporating partially fluorinated n-propyl and n-butyl groups is described along with an in-depth study of the effects of various fluorination patterns on their properties, such as lipophilicity, aqueous solubility, and metabolic stability.
Abstract: The synthesis of a collection of 3-substituted indole derivatives incorporating partially fluorinated n-propyl and n-butyl groups is described along with an in-depth study of the effects of various fluorination patterns on their properties, such as lipophilicity, aqueous solubility, and metabolic stability. The experimental observations confirm predictions of a marked lipophilicity decrease imparted by a vic-difluoro unit when compared to the gem-difluoro counterparts. The data involving the comparison of the two substitution patterns is expected to benefit molecular design in medicinal chemistry and, more broadly, in life as well as materials sciences.
TL;DR: A series of 2,2'-diselenobisbenzoic scaffold, amino acid, and benzenesulfonamide derivatives are identified as novel HIV retroviral nucleocapsid protein 7 (NCp7) inhibitors and their mechanism of action is based on NCp7 inhibition.
Abstract: The interest in the synthesis of Se-containing compounds is growing with the discovery of derivatives exhibiting various biological activities. In this manuscript, we have identified a series of 2,2′-diselenobisbenzamides (DISeBAs) as novel HIV retroviral nucleocapsid protein 7 (NCp7) inhibitors. Because of its pleiotropic functions in the whole viral life cycle and its mutation intolerant nature, NCp7 represents a target of great interest which is not reached by any anti-HIV agent in clinical use. Using the diselenobisbenzoic scaffold, amino acid, and benzenesulfonamide derivatives were prepared and biologically profiled against different models of HIV infection. The incorporation of amino acids such as glycine and glutamate into DISeBAs 7 and 8 resulted in selective anti-HIV activity against both acutely and chronically infected cells as well as an interesting virucidal effect. DISeBAs demonstrated broad antiretroviral activity, encompassing HIV-1 drug-resistant strains including clinical isolates, as w...
TL;DR: The discovery and development of orally bioavailable SERDs provide the opportunity to evaluate the utility of eliminating ERα expression in advanced metastatic breast cancers, and the mechanisms underlying resistance to existing agents are complex.
Abstract: Drugs that inhibit estrogen receptor alpha (ERα) or that block the production of estrogens remain frontline interventions in the treatment and management of breast cancer at all stages. However, resistance to endocrine therapies, especially in the setting of advanced disease, remains an impediment to durable clinical responses. Although the mechanisms underlying resistance to existing agents are complex, preclinical studies suggest that selective estrogen receptor downregulators (SERDs), molecules which eliminate ERα expression, may have particular utility in the treatment of breast cancers that have progressed on tamoxifen and/or aromatase inhibitors. The discovery and development of orally bioavailable SERDs provide the opportunity to evaluate the utility of eliminating ERα expression in advanced metastatic breast cancers.
TL;DR: The discovery of an orally bioavailable selective estrogen receptor downregulator (SERD) with equivalent potency and preclinical pharmacology to the intramuscular SERD fulvestrant is described.
Abstract: The discovery of an orally bioavailable selective estrogen receptor downregulator (SERD) with equivalent potency and preclinical pharmacology to the intramuscular SERD fulvestrant is described. A directed screen identified the 1-aryl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole motif as a novel, druglike ER ligand. Aided by crystal structures of novel ligands bound to an ER construct, medicinal chemistry iterations led to (E)-3-(3,5-difluoro-4-((1R,3R)-2-(2-fluoro-2-methylpropyl)-3-methyl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-1-yl)phenyl)acrylic acid (30b, AZD9496), a clinical candidate with high oral bioavailability across preclinical species that is currently being evaluated in phase I clinical trials for the treatment of advanced estrogen receptor (ER) positive breast cancer.
TL;DR: Antitumor mechanism and target profiling studies indicate that compound 66c is the first-in-class triple topoisomerase I/topoisomersase II/tubulin inhibitor.
Abstract: A critical question in natural product-based drug discovery is how to translate the product into drug-like molecules with optimal pharmacological properties. The generation of natural product-inspired scaffold diversity is an effective but challenging strategy to investigate the broader chemical space and identify promising drug leads. Extending our efforts to the natural product evodiamine, a diverse library containing 11 evodiamine-inspired novel scaffolds and their derivatives were designed and synthesized. Most of them showed good to excellent antitumor activity against various human cancer cell lines. In particular, 3-chloro-10-hydroxyl thio-evodiamine (66c) showed excellent in vitro and in vivo antitumor efficacy with good tolerability and low toxicity. Antitumor mechanism and target profiling studies indicate that compound 66c is the first-in-class triple topoisomerase I/topoisomerase II/tubulin inhibitor. Overall, this study provided an effective strategy for natural product-based drug discovery.
TL;DR: It is discovered that the number of structurally validated type II inhibitors that can be found in the PDB and that are also represented in publicly available biochemical profiling studies of kinase inhibitors is very small.
Abstract: Structural coverage of the human kinome has been steadily increasing over time. The structures provide valuable insights into the molecular basis of kinase function and also provide a foundation for understanding the mechanisms of kinase inhibitors. There are a large number of kinase structures in the PDB for which the Asp and Phe of the DFG motif on the activation loop swap positions, resulting in the formation of a new allosteric pocket. We refer to these structures as “classical DFG-out” conformations in order to distinguish them from conformations that have also been referred to as DFG-out in the literature but that do not have a fully formed allosteric pocket. We have completed a structural analysis of almost 200 small molecule inhibitors bound to classical DFG-out conformations; we find that they are recognized by both type I and type II inhibitors. In contrast, we find that nonclassical DFG-out conformations strongly select against type II inhibitors because these structures have not formed a large...
TL;DR: An overview of the discovery of the potent and selective p53:MDM2 inhibitor NVP-CGM097 with an excellent in vivo profile is provided, which is currently in phase 1 clinical development.
Abstract: As a result of our efforts to discover novel p53:MDM2 protein–protein interaction inhibitors useful for treating cancer, the potent and selective MDM2 inhibitor NVP-CGM097 (1) with an excellent in vivo profile was selected as a clinical candidate and is currently in phase 1 clinical development. This article provides an overview of the discovery of this new clinical p53:MDM2 inhibitor. The following aspects are addressed: mechanism of action, scientific rationale, binding mode, medicinal chemistry, pharmacokinetic and pharmacodynamic properties, and in vivo pharmacology/toxicology in preclinical species.
TL;DR: Mechanistic insights indicate that both Pt1 and Pt2 display low toxicity and could be novel anticancer drug candidates.
Abstract: Two G-quadruplex ligands [Pt(L(a))(DMSO)Cl] (Pt1) and [Pt(L(b))(DMSO)Cl] (Pt2) have been synthesized and fully characterized. The two complexes are more selective for SK-OV-3/DDP tumor cells versus normal cells (HL-7702). It was found that both Pt1 and Pt2 could be a telomerase inhibitor targeting G-quadruplex DNA. This is the first report demonstrating that telomeric, c-myc, and bcl-2 G-quadruplexes and caspase-3/9 preferred to bind with Pt2 rather than Pt1, which also can induce senescence and apoptosis. The different biological behavior of Pt1 and Pt2 may correlate with the presence of a 6-hydroxyl group in L(b). Importantly, Pt1 and Pt2 exhibited higher safety in vivo and more effective inhibitory effects on tumor growth in the HCT-8 and NCI-H460 xenograft mouse model, compared with cisplatin. Taken together, these mechanistic insights indicate that both Pt1 and Pt2 display low toxicity and could be novel anticancer drug candidates.
TL;DR: Findings indicate that the pyrimidine-thiourea-based LSD1 inactivator may serve as a leading compound targeting LSD1 overexpressed cancers.
Abstract: Histone lysine specific demethylase 1 (LSD1) was reported to be overexpressed in several human cancers and recognized as a promising anticancer drug target. In the current study, we designed and synthesized a novel series of pyrimidine–thiourea hybrids and evaluated their potential LSD1 inhibitory effect. One of the compounds, 6b, containing a terminal alkyne appendage, was shown to be the most potent and selective LSD1 inhibitor in vitro and exhibited strong cytotoxicity against LSD1 overexpressed gastric cancer cells. Compound 6b also showed marked inhibition of cell migration and invasion as well as significant in vivo tumor suppressing and antimetastasis role, without significant side effects by oral administration. Our findings indicate that the pyrimidine–thiourea-based LSD1 inactivator may serve as a leading compound targeting LSD1 overexpressed cancers.
TL;DR: Lead optimization efforts focused on in vitro potency, ADME, and pharmaceutical properties that led to the discovery of a potent, ATP-competitive, D2-selective, and orally bioavailable p97 inhibitor 71, CB-5083 are described.
Abstract: The AAA-ATPase p97 plays vital roles in mechanisms of protein homeostasis, including ubiquitin–proteasome system (UPS) mediated protein degradation, endoplasmic reticulum-associated degradation (ERAD), and autophagy. Herein we describe our lead optimization efforts focused on in vitro potency, ADME, and pharmaceutical properties that led to the discovery of a potent, ATP-competitive, D2-selective, and orally bioavailable p97 inhibitor 71, CB-5083. Treatment of tumor cells with 71 leads to significant accumulation of markers associated with inhibition of UPS and ERAD functions, which induces irresolvable proteotoxic stress and cell death. In tumor bearing mice, oral administration of 71 causes rapid accumulation of markers of the unfolded protein response (UPR) and subsequently induces apoptosis leading to sustained antitumor activity in in vivo xenograft models of both solid and hematological tumors. 71 has been taken into phase 1 clinical trials in patients with multiple myeloma and solid tumors.