Abstract: The present invention provides novel hydroxylamine derivatives represented by the general formula: wherein:X is O, --NH, or a group of formula NR', wherein R and R' are independently selected from alkyl, cycloalkyl, phenylalkyl, phenyl optionally substituted with halo, haloalkyl,alkyl, alkoxy or nitro; and a N-containing heterocyclic ring;R.sup.1 is H or alkanoyl,R.sup.2 is H or hydroxy optionally acylated with alkanoyl, andR.sup.3 is a group of the formula --NR.sup.4 R.sup.5 wherein R.sup.4 and R.sup.5 are independently selected fromH, alkyl, and a group of the formula --CO--NH--R wherein R is as defined above, orwherein R.sup.4 and R.sup.5 when taken together form a 5- to 7-membered heterocyclic ring which may optionally contain one additional hetero atom selected from nitrogen, oxygen and sulfur and which is optionally substituted with alkyl or phenylalkyl.