Jianchang Li

A Selective Matrix Metalloprotease 12 Inhibitor for Potential Treatment of Chronic Obstructive Pulmonary Disease (COPD): Discovery of (S)-2-(8-(Methoxycarbonylamino)dibenzo[b,d]furan-3-sulfonamido)-3-methylbutanoic acid (MMP408)

Matrix metalloprotease 12 plays a significant role in airway inflammation and remodeling. Increased expression and production of MMP-12 have been found in the lung of human COPD patients. MMP408 (14), a potent and selective MMP-12 inhibitor, was derived from a potent matrix metalloprotease 2 and 13 inhibitor via lead optimization and has good physical properties and bioavailability. The compound blocks rhMMP-12-induced lung inflammation in a mouse model and was advanced for further development for the treatment of COPD.

Identification of an orally efficacious matrix metalloprotease 12 inhibitor for potential treatment of asthma.

MMP-12 plays a significant role in airway inflammation and remodeling. Increased expression and production of MMP-12 have been observed in the lungs of asthmatic patients. Compound 27 was identified as a potent and selective MMP-12 inhibitor possessing good physicochemical properties. In pharmacological studies, the compound was orally efficacious in an MMP-12 induced ear-swelling inflammation model in the mouse with a good dose response. This compound also exhibited oral efficacy in a naturally Ascaris-sensitized sheep asthma model showing significant inhibition of the late phase response to allergen challenge. This compound has been considered for further development as a treatment therapy for asthma.

Mechanistic pathways in CF3COOH-mediated deacetalization reactions.

It has been widely accepted that both the protection of carbonyls and the deprotection of acetals and ketals involve the participation of a water molecule: formation of acetals and ketals is a dehydration process, whereas the deprotection is often referred to as hydrolysis, which, as implied by its name, always requires the presence of water. Herein, we report experimental evidence and mechanistic investigations that provide an alternative view to this process. We have demonstrated that water is not required to convert acetals and ketals to the corresponding carbonyls. The (1)H NMR experimental results revealed that the TFA-mediated transformation of acetal to aldehyde occurs via a hemiacetal TFA ester intermediate, which differentiates itself from the classic acid-catalyzed hydrolysis, where the hemiacetal is the putative intermediate responsible for the formation of the aldehyde. More interestingly, alcohols are not the final byproducts as they are in the classical hydrolysis, rather, the two alcohol molecules are converted to two TFA esters under the reaction conditions. On the basis of the NMR evidence, we have proposed that the two TFA esters are formed in two separate steps via a different mechanism along the reaction pathway. Formation of the TFA esters renders the reaction irreversible. To the best of our knowledge, the cascade reaction pathway presented by the TFA-mediated conversion of acetals and ketals to carbonyls has never been previously postulated.

Discovery of potent and selective matrix metalloprotease 12 inhibitors for the potential treatment of chronic obstructive pulmonary disease (COPD).

Chronic obstructive pulmonary disease (COPD) is an inflammatory lung disease associated with irreversible progressive airflow limitation. Matrix metalloproteinase-12 (MMP-12) has been characterized to be one of the major proteolytic enzymes to induce airway remodeling, destruction of elastin and the aberrant remodeling of damaged alveoli in COPD and asthma. The goal of this project is to develop and identify an orally potent and selective small molecule inhibitor of MMP-12 for treatment of COPD and asthma. Syntheses and structure-activity relationship (SAR) studies of a series of dibenzofuran (DBF) sulfonamides as MMP-12 inhibitors are described. Potent inhibitors of MMP-12 with excellent selectivity against other MMPs were identified. Compound 26 (MMP118), which exhibits excellent oral efficacy in the MMP-12 induced ear-swelling inflammation and lung inflammation mouse models, had been successfully advanced into Development Track status.