Photoreactive analogues of prenyl diphosphates have been useful in studying prenyltransferases. The effectiveness of analogues with different chain lengths as probes of recombinant human protein prenyltransferases is established here. A putative geranylgeranyl diphosphate analogue, 2-diazo-3,3,3-trifluoropropionyloxy-farnesyl diphosphate (DATFP-FPP), was the best inhibitor of both protein farnesyltransferase (PFT) and protein geranylgeranyltransferase-I (PFFT-I). Shorter photoreactive isprenyl diphosphate analogues with geranyl and dimethylallyl moieties and the DATFP-derivative of farnesyl monophosphate were much poorer inhibitors. DATFP-FPP was a competitive inhibitor of both PFT and PGGT-I with Ki values of 100 and 18 nM, respectively. [32P]DATFP-FPP specifically photoradiolabelled the beta-subunits of both PFT and PGGT-I. Photoradiolabelling of PGGT-I was inhibited more effectively by geranylgeranyl diphosphate than farnesyl diphosphate, whereas photoradiolabelling of PFT was inhibited better by farnesyl diphosphate than geranylgeranyl diphosphate. These results lead to the conclusions that DATFP-FPP is an effective probe of the prenyl diphosphate binding domains of PFT and PGGT-I. Furthermore, the beta-subunits of protein prenyltransferases must contribute significantly to the recognition and binding of the isoprenoid substrate.

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Mineralocorticoid receptor (MR) antagonists continue to be a prevalent area of research in the pharmaceutical industry. Herein we report the discovery of various spirooxindole and dibenzoxazepine constructs as potent MR antagonists. SAR analysis of our spirooxindole hit led to highly potent compounds containing polar solubilizing groups, which interact with the helix-11 region of the MR ligand binding domain (LBD). Various dibenzoxazepine moieties were also prepared in an effort to replace a known dibenzoxepane system which interacts with the hydrophobic region of the MR LBD. In addition, an X-ray crystal structure was obtained from a highly potent compound which was shown to exhibit both partial agonist and antagonist modes of action against MR.

Structure guided optimization of a series of nonpeptidic alkyl amine renin inhibitors allowed the rational incorporation of additional polar functionality. Replacement of the cyclohexylmethyl group occupying the S1 pocket with a (R)-(tetrahydropyran-3-yl)methyl group and utilization of a different attachment point led to the identification of clinical candidate 9. This compound demonstrated excellent selectivity over related and unrelated off-targets, >15% oral bioavailability in three species, oral efficacy in a double transgenic rat model of hypertension, and good exposure in humans.

Structure based design led directly to 1,3-oxazinan-2-one 9a with an IC(50) of 42 nM against 11β-HSD1 in vitro. Optimization of 9a for improved in vitro enzymatic and cellular potency afforded 25f with IC(50) values of 0.8 nM for the enzyme and 2.5 nM in adipocytes. In addition, 25f has 94% oral bioavailability in rat and >1000× selectivity over 11β-HSD2. In mice, 25f was distributed to the target tissues, liver, and adipose, and in cynomolgus monkeys a 10 mg/kg oral dose reduced cortisol production by 85% following a cortisone challenge.