4-Bicyclic heteroaryl-piperidine derivatives as potent, orally bioavailable stearoyl-CoA desaturase-1 (SCD1) inhibitors: part 2. Pyridazine-based analogs.

Design, synthesis, and biological evaluation of pyridazine-based, 4-bicyclic heteroaryl-piperidine derivatives as potent stearoyl-CoA desaturase-1 (SCD1) inhibitors are described. In a chronic study of selected analog (3e) in Zucker fa/fa (ZF) rat, dose-dependent decrease of body weight gain and plasma fatty acid desaturation index (DI) in both C16 and C18 are also demonstrated. The results indicate that the plasma fatty acid DI may serve as an indicator for direct target engagement and biomarker for SCD1 inhibition.

Design and synthesis of potent inhibitors of cholesteryl ester transfer protein (CETP) exploiting a 1,2,3,4-tetrahydroquinoline platform.

Tetrahydroquinoline A is a potent inhibitor of the cholesterol ester transfer protein (CETP), a target for the treatment of low HDL-C and atherosclerosis. Low HDL-C has been identified as a key risk factor for cardiovascular disease in addition to high LDL-C, the target of the statin drugs. Tetrahydroquinoline A inhibits partially purified CETP with an IC(50) of 39nM. The preparation of a series of potent inhibitors of CETP designed around a 1,2,3,4-tetrahydroquinoline platform will be discussed.

Improved asymmetric synthesis of 3,4-dihydro-2-[3-(1,1,2,2-tetrafluoroethoxy)phenyl]-5-[3-(trifluoromethoxy)phenyl]-alpha-(trifluoromethyl)-1(2H)-quinolineethanol, a potent cholesteryl ester transfer protein inhibitor.

The asymmetric synthesis of 3,4-dihydro-2-[3-(1,1,2,2-tetrafluoroethoxy)phenyl]-5-[3-(trifluoromethoxy)phenyl]-alpha-(trifluoromethyl)-1(2H)-quinolineethanol (compound 11), a cholesteryl ester transfer protein inhibitor, is accomplished. The asymmetric center is established via the chiral reduction of ketone 4 employing Corey's (R)-Me CBS oxazaborolidine reagent. The tetrahydroquinoline core of the molecule is established via a Cu-mediated intramolecular amination reaction. The preparation of the prochiral ketone 4 has also been improved by eliminating the use of a hazardous aryltin reagent.

Design, synthesis, and biological evaluation of (2R,alphaS)-3,4-dihydro-2-[3-(1,1,2,2-tetrafluoroethoxy)phenyl]-5-[3-(trifluoromethoxy)-phenyl]-alpha-(trifluoromethyl)-1(2H)-quinolineethanol as potent and orally active cholesteryl ester transfer protein inhibitor.

With the goal of identifying a CETP inhibitor with high in vitro potency and optimal in vivo efficacy, a conformationally constrained molecule was designed based on the highly potent and flexible 13. The synthetic chemistry efforts led to the discovery of the potent and selective 12. In high-fat fed hamsters, human CETP transgenic mice, and cynomolgus monkeys, the in vivo efficacy of 12 for raising HDL-C was demonstrated to be comparable to torcetrapib.

Indinavir analogues with blocked metabolism sites as HIV protease inhibitors with improved pharmacological profiles and high potency against PI-resistant viral strains.

Indinavir analogues with blocked metabolism sites show highly improved pharmacokinetic profiles in animals. The cis-aminochromanol substituted analogues exhibited excellent potency against both the wild-type (NL4-3) virus and protease inhibitor-resistant HIV strains.

HIV protease inhibitors with picomolar potency against PI-Resistant HIV-1 by extension of the P3 substituent.

A biaryl pyridylfuran P(3) substituent on the hydroxyethylene isostere scaffold affords HIV protease inhibitors (PI's) with picomolar (IC(50)) potency against the protease enzymes from PI-resistant HIV-1 strains. Inclusion of a gem-dimethyl substituent afforded compound 3 with 100% oral bioavailability (dogs) and more than double the t(1/2) of indinavir. Inhibition of multiple P450 isoforms is dependent on the regiochemistry of the pyridyl nitrogen in these compounds.

A combinatorial library of indinavir analogues and its in vitro and in vivo studies.

A combinatorial library of 300HIV protease inhibitors has been synthesized. The library was screened against recombinant wild-type and mutant HIV-1 protease enzymes. The pharmacokinetics of the library was evaluated by dosing in dogs. Compounds that are notably more potent than indinavir and have favorable pharmacokinetic properties were identified.