Alessandra Bartolozzi

Synthesis, SAR, and series evolution of novel oxadiazole-containing 5-lipoxygenase activating protein inhibitors: discovery of 2-[4-(3-{(r)-1-[4-(2-amino-pyrimidin-5-yl)-phenyl]-1-cyclopropyl-ethyl}-[1,2,4]oxadiazol-5-yl)-pyrazol-1-yl]-N,N-dimethyl-acetamide (BI 665915).

The synthesis, structure-activity relationship (SAR), and evolution of a novel series of oxadiazole-containing 5-lipoxygenase-activating protein (FLAP) inhibitors are described. The use of structure-guided drug design techniques provided compounds that demonstrated excellent FLAP binding potency (IC50 < 10 nM) and potent inhibition of LTB4 synthesis in human whole blood (IC50 < 100 nM). Optimization of binding and functional potencies, as well as physicochemical properties resulted in the identification of compound 69 (BI 665915) that demonstrated an excellent cross-species drug metabolism and pharmacokinetics (DMPK) profile and was predicted to have low human clearance. In addition, 69 was predicted to have a low risk for potential drug-drug interactions due to its cytochrome P450 3A4 profile. In a murine ex vivo whole blood study, 69 demonstrated a linear dose-exposure relationship and a dose-dependent inhibition of LTB4 production.

Development of an asymmetric synthesis of a chiral quaternary FLAP inhibitor.

A practical sequence involving a noncryogenic stereospecific boronate rearrangement followed by a robust formylation with an in situ generated DCM anion has been developed for the asymmetric construction of an all-carbon quaternary stereogenic center of a FLAP inhibitor. The key boronate rearrangement was rendered noncryogenic and robust by using LDA as the base and instituting an in situ trapping of the unstable lithiated benzylic carbamate with the boronic ester. A similar strategy was implemented for the DCM formylation reaction. It was found that the 1,2-boronate rearrangement for the formylation reaction could be temperature-controlled, thus preventing overaddition of the DCM anion and rendering the process reproducible. The robust stereospecific boronate rearrangement and formylation were utilized for the practical asymmetric synthesis of a chiral quaternary FLAP inhibitor.

Selective CB2 receptor agonists. Part 3: The optimization of a piperidine-based series that demonstrated efficacy in an in vivo neuropathic pain model

A novel class of potent cannabinoid receptor 2 (CB2) agonists based on a (S)-piperidine scaffold was identified using ligand-based pharmacophore models. Optimization of solubility and metabolic stability led to the identification of several potent CB2 agonists (e.g., 30) that displayed selectivity over cannabinoid receptor 1 (CB1) and acceptable drug like properties. In rats, compound 30 demonstrated a favorable pharmacokinetic profile and efficacy in a Streptozotocin-induced diabetic neuropathy model, with full reversal of mechanical hyperalgesia.

Increased building block access through collaboration

We detail the formation of a pilot multipharmaceutical-company-chemical-vendor Buying Group that successfully facilitated access to fluorinated building blocks of high interest to medicinal chemists for analog synthesis at significantly reduced prices. This exercise showed significant overlap in building block interests among the participants and suggests that creative approaches to access building blocks is of common interest to medicinal chemists and will be valuable as the challenges of drug discovery continue to call for more-highly-tuned drug candidates that can be synthesized quickly.

Discovery and optimization of oxadiazole-based FLAP inhibitors

Structure activity relationship (SAR) investigation of an oxadiazole based series led to the discovery of several potent FLAP inhibitors. Lead optimization focused on achieving functional activity while improving physiochemical properties and reducing hERG inhibition. Several compounds with favorable in vitro and in vivo properties were identified that were suitable for advanced profiling.

Inflammatory Targets for the Treatment of Atherosclerosis

Abstract Atherosclerosis is a complex disease of the aterial wall and is the primary cause of coronary artery disease, peripheral vascular disease, and stroke and, thus, a leading cause of death worldwide. Despite many clinically useful treatment options for managing atherosclerosis in at risk patients, there remains a high residual risk for major adverse cardiovascular events. Recently, an improved appreciation of the role of inflammation play in the pathogenesis of atherosclerosis has revealed many druggable targets suitable for small molecule intervention. Here in, we present select evidence, both clinical and preclinical, for small molecule druggable anti-inflammatory targets. While the optimization and clinical programs against these targets may not have been initially directed toward their potential to treat atherosclerosis, the availability of high-quality chemical matter against a variety of targets should allow for clinical proof-of-concept studies to be conducted and hypotheses tested.