A series of novel benzoheterocyclic [(methoxyphenyl) amino] oxoalkanoic acid esters has been prepared. These compounds were tested as inhibitors of rat polymorphonuclear leukocyte 5-lipoxgenase (LO) in vitro and as inhibitors of leukotriene D,(LTD4) and ovalbumin (OA) induced bronchospasm in the guinea pig (GP) in vivo. In general, inhibitory activity against 5-L0, LTD4, and OA was broadest for benzthiazole-containing analogues ( ...