Design and Synthesis of Isoquinolidinobenzodiazepine Dimers, a Novel Class of Antibody-Drug Conjugate Payload.

Antibody-drug conjugates (ADCs) represent an important class of emerging cancer therapeutics. Recent ADC development efforts highlighted the use of pyrrolobenzodiazepine (PBD) dimer payload for the treatment of several cancers. We identified the isoquinolidinobenzodiazepine (IQB) payload (D211), a new class of PBD dimer family of DNA damaging payloads.

Eradication of Tumors through Simultaneous Ablation of CD276/B7-H3-Positive Tumor Cells and Tumor Vasculature.

Targeting the tumor vasculature with antibody-drug conjugates (ADCs) is a promising anti-cancer strategy that in order to be realized must overcome several obstacles, including identification of suitable targets and optimal warheads. Here, we demonstrate that the cell-surface protein CD276/B7-H3 is broadly overexpressed by multiple tumor types on both cancer cells and tumor-infiltrating blood vessels, making it a potentially ideal dual-compartment therapeutic target. In preclinical studies CD276 ADCs armed with a conventional MMAE warhead destroyed CD276-positive cancer cells, but were ineffective against tumor vasculature.

Discovery of a novel series of potent MK2 non-ATP competitive inhibitors using 1,2-substituted azoles as cis-amide isosteres.

A unified strategy was conceived and implemented to deliver conformationally constrained anilides based on their preferred cis-amide conformers. The imidazole/triazole mimicing amide bonds were designed, building upon an earlier discovery of a novel series of tricyclic lactams MK2 kinase inhibitors. This approach enabled rapid, modular synthesis of structurally novel analogs.

Discovery of a potent thiadiazole class of histamine h3 receptor antagonist for the treatment of diabetes.

A series of novel 2-piperidinopiperidine thiadiazoles were synthesized and evaluated as new leads of histamine H3 receptor antagonists. The 4-(5-([1,4'-bipiperidin]-1'-yl)-1,3,4-thiadiazol-2-yl)-2-(pyridin-2-yl)morpholine (5u) displayed excellent potency and ex vivo receptor occupancy. Compound 5u was also evaluated in vivo for antidiabetic efficacy in STZ diet-induced obesity type 2 diabetic mice for 2 or 12 days.

Discovery of SCH 900271, a Potent Nicotinic Acid Receptor Agonist for the Treatment of Dyslipidemia.

Structure-guided optimization of a series of C-5 alkyl substituents led to the discovery of a potent nicotinic acid receptor agonist SCH 900271 (33) with an EC50 of 2 nM in the hu-GPR109a assay. Compound 33 demonstrated good oral bioavailability in all species. Compound 33 exhibited dose-dependent inhibition of plasma free fatty acid (FFA) with 50% FFA reduction at 1.

SAR studies of C2 ethers of 2H-pyrano[2,3-d]pyrimidine-2,4,7(1H,3H)-triones as nicotinic acid receptor (NAR) agonist.

Based on in house screening lead compound 1 for the NAR project, SAR studies have been focused on the modification of the C2 ethers of the pyrimidinedione core structure. In this effort, an unpredictable SAR trend was overcome in the alkyl ether and arylalkyl ether series to identify compound 24 with improved in vitro activity compared to nicotinic acid. More consistent and predictable SAR was achieved in the propargyl ether series.

A three-step protocol for lead optimization: quick identification of key conformational features and functional groups in the SAR studies of non-ATP competitive MK2 (MAPKAPK2) inhibitors.

A three-step protocol for SAR development was introduced and applied to the SAR studies of the MK2 inhibitor program. Following this protocol, key conformational features and functional groups for improving MK2 inhibitor activity were quickly identified. Through this effort, the initial gap observed between in vitro binding activity and cellular activity in the lead identification stage was very much reduced.

Discovery of a potent nicotinic Acid receptor agonist for the treatment of dyslipidemia.

Nicotinic acid has been used clinically for decades to control serum lipoproteins. Nicotinic acid lowers very low-density lipoprotein (VLDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, and lipoprotein-a (LPa), and it is also effective in raising high-density lipoprotein (HDL)-cholesterol. However, nicotinic acid has several side effects in clinical use.

Efficient cu-catalyzed asymmetric conjugate additions of alkylzincs to trisubstituted cyclic enones.

The first examples of efficient catalytic asymmetric conjugate addition (ACA) of alkylzincs to trisubstituted cyclic enones is disclosed. These Cu-catalyzed reactions proceed efficiently with five- and seven-membered ring substrates to afford the desired products in >/=95% ee. Intermediate enolates can be trapped with alkyl halides to generate a quaternary stereogenic center.

Cu-catalyzed asymmetric conjugate additions of alkylzinc reagents to acyclic aliphatic enones.

Cu-catalyzed enantioselective conjugate additions to acyclic aliphatic enones are reported. The resulting enolates may be functionalized intra- and intermolecularly, leading to the formation of an additional C-C bond. The utility of the present method is not limited to reactions involving Et2Zn; a variety of alkylzincs may be used.