Discovery of ((<i>S</i>)-5-(Methoxymethyl)-7-(1-methyl-1<i>H</i>-indol-2-yl)-2-(trifluoromethyl)-4,7-dihydropyrazolo[1,5-<i>a</i>]pyrimidin-6-yl)((<i>S</i>)-2-(3-methylisoxazol-5-yl)pyrrolidin-1-yl)methanone As a Potent and Selective I_Kur Inhibitor

Previously disclosed dihydropyrazolopyrimidines are potent and selective blockers of I_Kur current. A potential liability with this chemotype is the formation of a reactive metabolite which demonstrated covalent binding to protein in vitro. When substituted at the 2 or 3 position, this template yielded potent I_Kur inhibitors, with selectivity over <i>h</i>ERG which did not form reactive metabolites. Subsequent optimization for potency and PK properties lead to the discovery of ((<i>S</i>)-5-(methoxymethyl)-7-(1-methyl-1<i>H</i>-indol-2-yl)-2-(trifluoromethyl)-4,7-dihydropyrazolo­[1,5-<i>a</i>]­pyrimidin-6-yl)­((<i>S</i>)-2-(3-methylisoxazol-5-yl)­pyrrolidin-1-yl)­methanone (<b>13j</b>), with an acceptable PK profile in preclinical species and potent efficacy in the preclinical rabbit atrial effective refractory period (AERP) model

The major genetic determinants of HIV-1 control affect HLA class I peptide presentation.

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified &gt;300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection