The present application describes novel isoxazoline of formula I or II:
##STR00001## or pharmaceutically acceptable salt or prodrug forms
thereof, wherein A, R.sup.1, R.sup.2, R.sup.3, R.sup.4, Z, U, X, Y,
Z.sup.a, and n are defined in the present specification, which are useful
as inhibitors of matrix metalloproteinases (MMP), TNF-.alpha. converting
enzyme (TACE), or a combination thereof.