Abstract: A compound of formula (XXII): ##STR1## or a compound of formula (XXIII): ##STR2## wherein in formula (XXIII), j.sup.1 -1 is 1 to 4; and Q.sub.6 and Q.sub.7 are on the same carbon atom; and wherein, in formulae (XXII) and (XXIII), Q.sub.6 is NH.sub.2 and Q.sub.7 is H, and either p is 0 to 2 and q is 1; or p is 1 and q is 0 to 3; and one of R.sub.5 and R.sub.6 is hydrogen, C.sub.1-6 alkyl, phenyl or phenyl --C.sub.1-3 alkyl, which phenyl moieties may be substituted by C.sub.1-6 alkyl, C.sub.1-6 alkoxy, CF.sub.3 or halogen; and the other of R.sub.5 and R.sub.6 is hydrogen or C.sub.1-6 alkyl.