ABSTRACT
Reported herein is the design, synthesis, and pharmacologic characterization of a class of TRPV1 antagonists constructed on a benzo[d]imidazole platform that evolved from a biaryl amide lead. This design composes three sections: a 2-substituted 5-phenyl headgroup attached to the benzo[d]imidazole platform, which is tethered at the two position to a phenyl tail group. Optimization of this design led to the identification of 4 (mavatrep), comprising a trifluoromethyl-phenyl-vinyl tail. In a TRPV1 functional assay, using cells expressing recombinant human TRPV1 channels, 4 antagonized capsaicin-induced Ca(2+) influx, with an IC50 value of 4.6 nM. In the complete Freund's adjuvant- and carrageenan-induced thermal hypersensitivity models, 4 exhibited full efficacy, with ED80 values of 7.8 and 0.5 mg/kg, respectively, corresponding to plasma levels of 270.8 and 9.2 ng/mL, respectively. On the basis of its superior pharmacologic and safety profile, 4 (mavatrep) was selected for clinical development for the treatment of pain.
Subject(s)
Analgesics/chemistry , Benzimidazoles/chemistry , TRPV Cation Channels/antagonists & inhibitors , Analgesics/pharmacokinetics , Analgesics/pharmacology , Animals , Benzimidazoles/pharmacokinetics , Benzimidazoles/pharmacology , Biological Availability , Carrageenan , Dogs , Freund's Adjuvant , HEK293 Cells , Haplorhini , Hot Temperature , Humans , Hyperalgesia/chemically induced , Hyperalgesia/drug therapy , Hyperalgesia/physiopathology , Inflammation/chemically induced , Inflammation/drug therapy , Inflammation/physiopathology , Male , Mice , Microsomes, Liver/metabolism , Pain/chemically induced , Pain/drug therapy , Pain/physiopathology , Rats , Rats, Sprague-Dawley , Structure-Activity RelationshipABSTRACT
Thermosensitive transient receptor potential melastatin 8 (TRPM8) antagonists are considered to be potential therapeutic agents for the treatment of cold hypersensitivity. The discovery of a new class of TRPM8 antagonists that shows in vivo efficacy in the rat chronic constriction injury (CCI)-induced model of neuropathic pain is described.
Subject(s)
Analgesics/chemistry , Analgesics/therapeutic use , Benzimidazoles/chemistry , Benzimidazoles/therapeutic use , Hyperalgesia/drug therapy , Neuralgia/drug therapy , TRPM Cation Channels/antagonists & inhibitors , Analgesics/pharmacokinetics , Analgesics/pharmacology , Animals , Benzimidazoles/pharmacokinetics , Benzimidazoles/pharmacology , Cold Temperature , Dogs , HEK293 Cells , Humans , Rats , TRPM Cation Channels/metabolismABSTRACT
A series of piperidine carboxamides were developed as potent antagonists of the transient receptor potential vanilloid-1 (TRPV1), an emerging target for the treatment of pain. A focused library of polar head groups led to the identification of a benzoxazinone amide that afforded good potency in cell-based assays. Synthesis and a QSAR model will be presented.
Subject(s)
Amides/chemistry , Benzoxazines/pharmacology , Piperidines/chemistry , TRPV Cation Channels/antagonists & inhibitors , Benzoxazines/chemistry , Capsaicin/chemistry , Carrier Proteins/antagonists & inhibitors , Chemistry, Pharmaceutical/methods , Drug Design , Humans , Inhibitory Concentration 50 , Models, Chemical , Molecular Conformation , Protein Binding , Quantitative Structure-Activity Relationship , Structure-Activity RelationshipABSTRACT
Small molecule antagonists of protein-protein interactions represent a particular challenge for pharmaceutical discovery. One approach to finding molecules that can disrupt these interactions is to seek mimics of common protein structure motifs. We present an analysis of how molecules based on the 1,4-benzodiazepine-2,5-dione scaffold serve to mimic the side-chains presented by the hydrophobic face of two turns of an alpha-helix derived from the tumor suppressor protein p53, and thus antagonize the HDM2-p53 protein-protein binding interaction.
Subject(s)
Benzodiazepines/chemistry , Drug Design , Molecular Mimicry , Protein Interaction Mapping , Proto-Oncogene Proteins c-mdm2/antagonists & inhibitors , Proto-Oncogene Proteins c-mdm2/metabolism , Tumor Suppressor Protein p53/antagonists & inhibitors , Tumor Suppressor Protein p53/metabolism , Benzodiazepines/pharmacology , Humans , Protein Structure, Secondary/drug effects , Proto-Oncogene Proteins c-mdm2/chemistry , Tumor Suppressor Protein p53/chemistryABSTRACT
Guided by structure-based drug design, modification of the 1,4-benzodiazepin-2,5-dione lead compound 1 resulted in the discovery of 19, a potent and orally bioavailable antagonist of the HDM2-p53 protein-protein interaction (FP IC50 = 0.7 microM, F approximately 100%).
Subject(s)
Benzodiazepines/chemistry , Drug Design , Proto-Oncogene Proteins c-mdm2/antagonists & inhibitors , Proto-Oncogene Proteins c-mdm2/metabolism , Tumor Suppressor Protein p53/antagonists & inhibitors , Tumor Suppressor Protein p53/metabolism , Alkylation , Animals , Benzodiazepines/chemical synthesis , Cell Line, Tumor , Cell Membrane Permeability , Cell Proliferation/drug effects , Crystallography, X-Ray , Humans , Mice , Models, Molecular , Molecular Structure , Pentanoic Acids/chemistry , Protein Binding , Proto-Oncogene Proteins c-mdm2/chemistry , Structure-Activity Relationship , Tumor Suppressor Protein p53/chemistryABSTRACT
The activity and stability of the p53 tumor suppressor are regulated by the human homologue of the mouse double minute 2 (Hdm2) oncoprotein. It has been hypothesized that small molecules disrupting the Hdm2:p53 complex would allow for the activation of p53 and result in growth suppression. We have identified small-molecule inhibitors of the Hdm2:p53 interaction using our proprietary ThermoFluor microcalorimetry technology. Medicinal chemistry and structure-based drug design led to the development of an optimized series of benzodiazepinediones, including TDP521252 and TDP665759. Activities were dependent on the expression of wild-type (wt) p53 and Hdm2 as determined by lack of potency in mutant or null p53-expressing cell lines or cells engineered to no longer express Hdm2 and wt p53. TDP521252 and TDP665759 inhibited the proliferation of wt p53-expressing cell lines with average IC(50)s of 14 and 0.7 micromol/L, respectively. These results correlated with the direct cellular dissociation of Hdm2 from wt p53 observed within 15 minutes in JAR choriocarcinoma cells. Additional activities of these inhibitors in vitro include stabilization of p53 protein levels, up-regulation of p53 target genes in a DNA damage-independent manner, and induction of apoptosis in HepG2 cells. Administration of TDP665759 to mice led to an increase in p21(waf1/cip1) levels in liver samples. Finally, TDP665759 synergizes with doxorubicin both in culture and in an A375 xenograft model to decrease tumor growth. Taken together, these data support the potential utility of small-molecule inhibitors of the Hdm2:p53 interaction for the treatment of wt p53-expressing tumors.
Subject(s)
Benzodiazepinones/pharmacology , Doxorubicin/pharmacology , Proto-Oncogene Proteins c-mdm2/drug effects , Tumor Suppressor Protein p53/drug effects , Animals , Antineoplastic Combined Chemotherapy Protocols , Apoptosis/drug effects , Benzodiazepines/chemistry , Benzodiazepines/pharmacology , Benzodiazepinones/administration & dosage , Cell Line, Tumor , Cell Proliferation/drug effects , Doxorubicin/administration & dosage , Drug Screening Assays, Antitumor , Drug Synergism , Female , Humans , Liver Neoplasms, Experimental/drug therapy , Liver Neoplasms, Experimental/metabolism , Mice , Mice, Nude , Multiprotein Complexes , Mutation , Proto-Oncogene Proteins c-mdm2/metabolism , Tumor Cells, Cultured , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Xenograft Model Antitumor AssaysABSTRACT
HDM2 binds to an alpha-helical transactivation domain of p53, inhibiting its tumor suppressive functions. A miniaturized thermal denaturation assay was used to screen chemical libraries, resulting in the discovery of a novel series of benzodiazepinedione antagonists of the HDM2-p53 interaction. The X-ray crystal structure of improved antagonists bound to HDM2 reveals their alpha-helix mimetic properties. These optimized molecules increase the transcription of p53 target genes and decrease proliferation of tumor cells expressing wild-type p53.
Subject(s)
Benzodiazepines/chemical synthesis , Nuclear Proteins/antagonists & inhibitors , Proto-Oncogene Proteins/antagonists & inhibitors , Tumor Suppressor Protein p53/agonists , Benzodiazepines/chemistry , Benzodiazepines/pharmacology , Binding Sites , Cell Line, Tumor , Combinatorial Chemistry Techniques , Crystallography, X-Ray , Humans , Models, Molecular , Molecular Mimicry , Molecular Structure , Proto-Oncogene Proteins c-mdm2 , Stereoisomerism , Structure-Activity Relationship , Tumor Suppressor Protein p53/biosynthesisABSTRACT
A library of 1,4-benzodiazepine-2,5-diones was screened for binding to the p53-binding domain of HDM2 using Thermofluor, a miniaturized thermal denaturation assay. The hits obtained were shown to bind to HDM2 in the p53-binding pocket using a fluorescence polarization (FP) peptide displacement assay. The potency of the series was optimized, leading to sub-micromolar antagonists of the p53-HDM2 interaction.