Renee M. Chabin

Substituted 2-aminopyridines as inhibitors of nitric oxide synthase

A series of substituted 2-aminopyridines was prepared and evaluated as inhibitors of human nitric oxide synthases (NOS). 4,6-Disubstitution enhanced both potency and specificity for the inducible NOS with the most potent compound having an IC50 of 28 nM.

Inhibitors of the bacterial cell wall biosynthesis enzyme MurC.

A series of transition-state analog inhibitors of the D-glutamic acid-adding enzyme (MurD) of bacterial peptidoglycan biosynthesis has been synthesized and evaluated for inhibition of the E. coli enzyme.

Design and Synthesis of Prolylcarboxypeptidase (PrCP) Inhibitors To Validate PrCP As A Potential Target for Obesity

Prolylcarboxypeptidase (PrCP) is a serine protease that may have a role in metabolism regulation. A class of reversible, potent, and selective PrCP inhibitors was developed starting from a mechanism based design for inhibiting this serine protease. Compound 8o inhibits human and mouse PrCP at IC(50) values of 1 and 2 nM and is not active (IC(50) > 25 μM) against a panel of closely related proteases. It has lower serum binding than its close analogues and is bioavailable in mouse. Subchronic dosing of 8o in PrCP(-/-) and WT mice at 100 mg/kg for 5 days resulted in a 5% reduction in body weight in WT mice and a 1% reduction in PrCP KO mice.

Discovery of benzimidazole pyrrolidinyl amides as prolylcarboxypeptidase inhibitors

A series of benzimidazole pyrrolidinyl amides containing a piperidinyl group were discovered as novel prolylcarboxypeptidase (PrCP) inhibitors. Low-nanomolar IC(50)s were achieved for several analogs, of which compound 9b displayed modest ex vivo target engagement in eDIO mouse plasma. Compound 9b was also studied in vivo for its effect on weight loss and food intake in an eDIO mouse model and the results will be discussed.

The discovery of non-benzimidazole and brain-penetrant prolylcarboxypeptidase inhibitors.

Novel prolylcarboxypeptidase (PrCP) inhibitors with nanomolar IC(50) values were prepared by replacing the previously described dichlorobenzimidazole-substituted pyrrolidine amides with a variety of substituted benzylamine amides. In contrast to prior series, the compounds demonstrated minimal inhibition shift in whole serum and minimal recognition by P-glycoprotein (P-gp) efflux transporters. The compounds were also cell permeable and demonstrated in vivo brain exposure. The in vivo effect of compound (S)-6e on weight loss in an established diet-induced obesity (eDIO) mouse model was studied.

SYNTHESIS OF NEW THIAZINOINDOLE DERIVATIVES AND THEIR EVALUATION AS INHIBITORS OF HUMAN LEUKOCYTE ELASTASE AND OTHER RELATED SERINE PROTEASES

A novel thiazinoindole tricyclic ring system was designed as potential inhibitors of serine proteases. The compounds were synthesized by ring closure at 80–90°C in poliphosphoric acid of the appropriate N′-alkyl or aryl substituted indolylthiourea derivatives. Members of this class of compounds inhibited human leukocyte elastase (Ki=30–40 μM) and α-chymotrypsin.

Discovery of a new class of potent prolylcarboxypeptidase inhibitors derived from alanine.

Efforts to modify the central proline portion of lead compound 4 lead to the discovery of novel prolylcarboxypeptidase (PrCP) inhibitors. Especially, replacement with alanine afforded compound 19 displaying more potent human and mouse PrCP inhibitory activity than 4 and an overall comparable profile.

Discovery of benzodihydroisofurans as novel, potent, bioavailable and brain-penetrant prolylcarboxypeptidase inhibitors.

A series of benzodihydroisofurans were discovered as novel, potent, bioavailable and brain-penetrant prolylcarboxypeptidase (PrCP) inhibitors. The structure-activity relationship (SAR) is focused on improving PrCP activity and metabolic stability, and reducing plasma protein binding. In the established diet-induced obese (eDIO) mouse model, compound ent-3a displayed target engagement both in plasma and in brain. However, this compound failed to induce significant body weight loss in eDIO mice in a five-day study.

Discovery of aminoheterocycles as potent and brain penetrant prolylcarboxypeptidase inhibitors.

Efforts were dedicated to develop potent and brain penetrant prolylcarboxypeptidase (PrCP) inhibitors by replacing the amide group of original leads 1 and 2 with heterocycles. Aminopyrimidines including compound 32a were identified to display good PrCP inhibitory activity (32a, IC(50)=43 nM) and impressive ability to penetrate brain in mice (brain/plasma ratio: 1.4).

Phosphorous acid analogs of L-680,833, a potent monocyclic β-lactam inhibitor of human leukocyte elastase

Abstract Analogs of the monocyclic β-lactam human leukocyte elastase (HLE) inhibitor L-680,833 in which the carboxyl group is replaced by phosphorous acid moieties were synthesized and found to be potent inhibitors of the enzyme ( k inact / K i in the range 217,000–1,326,000 M −1 s −1 ). Cellular activity was demonstrated by inhibition of the generation of the N-terminal cleavage product Aα-(1–21) from the Aα chain of fibrinogen.