Optimization of cellular activity of G9a inhibitors 7-aminoalkoxy-quinazolines.

Protein lysine methyltransferase G9a plays key roles in the transcriptional repression of a variety of genes via dimethylation of lysine 9 on histone H3 (H3K9me2) of chromatin as well as dimethylation of nonhistone proteins including tumor suppressor p53. We previously reported the discovery of UNC0321 (3), the most potent G9a inhibitor to date, via structure-based design and structure-activity relationship (SAR) exploration of the quinazoline scaffold represented by BIX01294 (1). Despite its very high in vitro potency, compound 3 lacks sufficient cellular potency. The design and synthesis of several generations of new analogues aimed at improving cell membrane permeability while maintaining high in vitro potency resulted in the discovery of a number of novel G9a inhibitors such as UNC0646 (6) and UNC0631 (7) with excellent potency in a variety of cell lines and excellent separation of functional potency versus cell toxicity. The design, synthesis, and cellular SAR of these potent G9a inhibitors are described.

[1]  Jian Jin,et al.  Targets in Epigenetics: Inhibiting the Methyl Writers of the Histone Code , 2011, Current chemical genomics.

[2]  Peter A. DiMaggio,et al.  A chemical probe selectively inhibits G9a and GLP methyltransferase activity in cells. , 2011, Nature chemical biology.

[3]  Anton Simeonov,et al.  Protein lysine methyltransferase G9a inhibitors: design, synthesis, and structure activity relationships of 2,4-diamino-7-aminoalkoxy-quinazolines. , 2010, Journal of medicinal chemistry.

[4]  Aiming Sun,et al.  Adding a lysine mimic in the design of potent inhibitors of histone lysine methyltransferases. , 2010, Journal of molecular biology.

[5]  T. Okamoto,et al.  Involvement of Histone H3 Lysine 9 (H3K9) Methyltransferase G9a in the Maintenance of HIV-1 Latency and Its Reactivation by BIX01294* , 2010, The Journal of Biological Chemistry.

[6]  Stephen V Frye,et al.  The art of the chemical probe. , 2010, Nature chemical biology.

[7]  D. Reinberg,et al.  TILRR, a Novel IL-1RI Co-receptor, Potentiates MyD88 Recruitment to Control Ras-dependent Amplification of NF-κB* , 2009, The Journal of Biological Chemistry.

[8]  Annick Harel-Bellan,et al.  A subset of the histone H3 lysine 9 methyltransferases Suv39h1, G9a, GLP, and SETDB1 participate in a multimeric complex. , 2010, Molecular cell.

[9]  Paul Greengard,et al.  Essential Role of the Histone Methyltransferase G9a in Cocaine-Induced Plasticity , 2010, Science.

[10]  S. Frye,et al.  Targeting Methyl Lysine , 2010 .

[11]  S. Kako,et al.  EVI-1 interacts with histone methyltransferases SUV39H1 and G9a for transcriptional repression and bone marrow immortalization , 2010, Leukemia.

[12]  Anton Simeonov,et al.  Discovery of a 2,4-diamino-7-aminoalkoxyquinazoline as a potent and selective inhibitor of histone lysine methyltransferase G9a. , 2009, Journal of medicinal chemistry.

[13]  P. Greengard,et al.  Control of Cognition and Adaptive Behavior by the GLP/G9a Epigenetic Suppressor Complex , 2009, Neuron.

[14]  Robert A. Copeland,et al.  Protein methyltransferases as a target class for drug discovery , 2009, Nature Reviews Drug Discovery.

[15]  O. Gangisetty,et al.  Distinct Roles for Histone Methyltransferases G9a and GLP in Cancer Germ-Line Antigen Gene Regulation in Human Cancer Cells and Murine Embryonic Stem Cells , 2009, Molecular Cancer Research.

[16]  Dinshaw J. Patel,et al.  Haematopoietic malignancies caused by dysregulation of a chromatin-binding PHD finger , 2009, Nature.

[17]  D. Reinberg,et al.  Dynamic Histone H1 Isotype 4 Methylation and Demethylation by Histone Lysine Methyltransferase G9a/KMT1C and the Jumonji Domain-containing JMJD2/KDM4 Proteins*S⃞ , 2009, Journal of Biological Chemistry.

[18]  J. Snyder,et al.  Structural basis for G9a-like protein lysine methyltransferase inhibition by BIX-01294 , 2009, Nature Structural &Molecular Biology.

[19]  A. Ishizaka,et al.  Deregulation of histone lysine methyltransferases contributes to oncogenic transformation of human bronchoepithelial cells , 2008, Cancer Cell International.

[20]  D. Schübeler,et al.  DNA methylation in ES cells requires the lysine methyltransferase G9a but not its catalytic activity , 2008, The EMBO journal.

[21]  H. Kimura,et al.  G9a/GLP complexes independently mediate H3K9 and DNA methylation to silence transcription , 2008, The EMBO journal.

[22]  P. Cole,et al.  Chemical probes for histone-modifying enzymes. , 2008, Nature chemical biology.

[23]  J. Issa,et al.  Downregulation of Histone H3 Lysine 9 Methyltransferase G9a Induces Centrosome Disruption and Chromosome Instability in Cancer Cells , 2008, PloS one.

[24]  Dinshaw J. Patel,et al.  Multivalent engagement of chromatin modifications by linked binding modules , 2007, Nature Reviews Molecular Cell Biology.

[25]  Hideaki Kato,et al.  Alterations of DNA methylation and histone modifications contribute to gene silencing in hepatocellular carcinomas , 2007, Hepatology research : the official journal of the Japan Society of Hepatology.

[26]  A. Lund,et al.  Chromatin‐modifying proteins in cancer , 2007, APMIS : acta pathologica, microbiologica, et immunologica Scandinavica.

[27]  B. Chait,et al.  Methylation of a histone mimic within the histone methyltransferase G9a regulates protein complex assembly. , 2007, Molecular cell.

[28]  T. Kouzarides.  Chromatin Modifications and Their Function , 2007, Cell.

[29]  Karl Mechtler,et al.  Reversal of H3K9me2 by a small-molecule inhibitor for the G9a histone methyltransferase. , 2007, Molecular cell.

[30]  Kelly M. McGarvey,et al.  Silenced tumor suppressor genes reactivated by DNA demethylation do not return to a fully euchromatic chromatin state. , 2006, Cancer research.

[31]  Stacie L. Bulfer,et al.  A coupled fluorescent assay for histone methyltransferases. , 2005, Analytical biochemistry.

[32]  Hans Matter,et al.  Probing the subpockets of factor Xa reveals two binding modes for inhibitors based on a 2-carboxyindole scaffold: a study combining structure-activity relationship and X-ray crystallography. , 2005, Journal of medicinal chemistry.

[33]  Tsutomu Ohta,et al.  Histone methyltransferases G9a and GLP form heteromeric complexes and are both crucial for methylation of euchromatin at H3-K9. , 2005, Genes & development.

[34]  H. Kato,et al.  G9a histone methyltransferase plays a dominant role in euchromatic histone H3 lysine 9 methylation and is essential for early embryogenesis. , 2002, Genes & development.

[35]  C. Allis,et al.  Translating the Histone Code , 2001, Science.

[36]  C. Ponting,et al.  Regulation of chromatin structure by site-specific histone H3 methyltransferases , 2000, Nature.

[37]  C. Allis,et al.  The language of covalent histone modifications , 2000, Nature.

[38]  Abraham Nudelman,et al.  NMR Chemical Shifts of Common Laboratory Solvents as Trace Impurities. , 1997, The Journal of organic chemistry.