Inhibition of E-Selectin-, ICAM-1-, and VCAM-1-Mediated Cell Adhesion by Benzo[b]thiophene-, Benzofuran-, Indole-, and Naphthalene-2-carboxamides: Identification of PD 144795 as an Antiinflammatory Agent

It was previously reported that 3-alkoxybenzo[b]thiophene-2-carboxamides exemplified by 1, 5-methoxy-3-(1-methylethoxy)benzo[b]thiophene-2-carboxamide, decreased the adherence of neutrophils to activated endothelial cells by inhibiting the upregulation of the adhesion molecules E-selectin and ICAM-1 on the surface of the endothelium. This finding is extended here to a series of 3-thiobenzo[b]thiophene-2-carboxamides and also heterocyclic analogs of 1, including benzofurans, indoles, and napthalenes. The compounds that inhibited the expression of E-selectin and ICAM-1 had the same effect on the expression of VCAM-1. PD 144795, 5-methoxy-3-(1-methylethoxy)benzo[b]thiophene-2-carboxamide 1-oxide (44), the sulfoxide analog of 1, was orally active in several models of inflammation. The in vitro and in vivo activity of PD 144795 resided predominately in the S-enantiomer.