Michael A. Letavic

Synthesis and biological activity of selective pipecolic acid-based TNF-α converting enzyme (TACE) inhibitors

A series of novel, selective TNF-alpha converting enzyme inhibitors based on 4-hydroxy and 5-hydroxy pipecolate hydroxamic acid scaffolds is described. The potency and selectivity of TACE inhibition is dramatically influenced by the nature of the sulfonamide group which interacts with the S1 site of the enzyme. Substituted 4-benzyloxybenzenesulfonamides exhibit excellent TACE potency with >100x selectivity over inhibition of matrix metalloprotease-1 (MMP-1). Alkyl substituents on the ortho position of the benzyl ether moiety give the most potent inhibition of TNF-alpha release in LPS-treated human whole blood.

Synthesis and activity of a novel class of tribasic macrocyclic antibiotics: the triamilides.

The stereoselective synthesis of two novel series of tribasic macrocyclic antibiotics with potent in vitro activity against Pasteurella multocida and Escherichia coli strains of bacteria is described. The in vitro activity can be significantly influenced by the nature of the substituents on the C-4 aminoalcohol, with the stereochemistry of the C-4 alcohol playing a less critical role. The effect of substitution and stereochemistry on the in vivo activity in a murine model of respiratory infection is also described.

Synthesis and biological activity of piperazine-Based dual MMP-13 and TNF-α converting enzyme inhibitors

Abstract A series of novel MMP-13 and TNF-α converting enzyme inhibitors based on piperazine 2-hydroxamic acid scaffolds are described. The TACE, MMP-1 and MMP-13 activity of these inhibitors as well as the effect of substitution of the piperazine nitrogen and the P-1′ benzyloxy tailpiece is discussed. Moderate in vivo activity is observed with several members of this group.

Continued exploration of the triazolopyridine scaffold as a platform for p38 MAP kinase inhibition

The structure based drug design, synthesis and structure-activity relationship of a series of C6 sulfur linked triazolopyridine based p38 inhibitors are described. The metabolic deficiencies of this series were overcome through changes in the C6 linker from sulfur to methylene, which was predicted by molecular modeling to be bioisosteric. X-ray of the ethylene linked compound 61 confirmed the predicted binding orientation of the scaffold in the p38 enzyme.

Synthesis, stereochemical assignment and biological activity of a novel series of C-4" modified aza-macrolides.

Modification of the cladinose C-4 position via manipulation of the corresponding keto derivatives afforded two stereochemically pure series of compounds. The synthesis and structure determination of these compounds is described within. The in vitro and in vivo biological activity of this novel series of C-4 modified macrolides is also described.