Hydroxylamine bearing amino acid derivatives as collagenase inhibitors

Abstract

Compounds of the formula ##STR1## wherein A is a group of the formula HN(OH)--CO-- or HCO--N(OH)--; R.sup.1 is a C.sub.2 -C.sub.5 -alkyl; R.sup.2 is the characterizing group of a natural .alpha.-amino acid in which any functional group present may be protected, any amino group present may be acylated and any carboxyl group present may be amidated, with the proviso that R.sup.2 is not hydrogen or methyl; R.sup.3 is hydrogen, amino, hydroxy, mercapto, C.sub.1 -C.sub.6 -alkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.6 -alkylamino, C.sub.1 -C.sub.6 -alkylthio or aryl-(C.sub.1 -C.sub.6 -alkyl), or amino-(C.sub.1 -C.sub.6 -alkyl), hydroxy-(C.sub.1 -C.sub.6 -alkyl), mercapto-(C.sub.1 -C.sub.6 -alkyl) or carboxy-(C.sub.1 -C.sub.6 -alkyl) in which the amino, hydroxy, mercapto or carboxyl group may be protected, the amino group may be acylated or the carboxyl group may be amidated; R.sup.4 is hydrogen or methyl; R.sup.5 is hydrogen or a C.sub.1 -C.sub.6 -alkyl, C.sub.1 -C.sub.6 -alkoxy-C.sub.1 -C.sub.6 -alkyl, di(C.sub.1 -C.sub.6 -alkoxy)-methylene, carboxyl, (C.sub.1 -C.sub.6 -alkyl)-carbonyl, (C.sub.1 -C.sub.6 -alkoxy)carbonyl, arylmethoxycarbonyl, (C.sub.1 -C.sub.6 -alkyl)aminocarbonyl or arylaminocarbonyl; and R.sup.6 is hydrogen or methyl; or R.sup.2 and R.sup.4 taken together are a group of the formula --(CH.sub.2).sub.n -- in which n is a number from 4 to 11; or R.sup.4 and R.sup.6 taken together are a trimethylene; and pharmaceutically acceptable salts of those compounds which are acidic or basic are described. The compounds of formula I possess collagenase inhibitory activity and can be used in the control or prevention of degenerative joint diseases.