$ perl -le'$_=pop;/([\$@*%]|(<))(.*)(?(2)>)/;print"($1)($3)"' '$xyz'
($)(xyz)
$ perl -le'$_=pop;/([\$@*%]|(<))(.*)(?(2)>)/;print"($1)($3)"' '$xyz>'
($)(xyz>)
$ perl -le'$_=pop;/([\$@*%]|(<))(.*)(?(2)>)/;print"($1)($3)"' '<xyz>'
(<)(xyz)