use strict;
my $str = 'https://test.ixtract.de/infografik-kategorien/prozess/';
my $regex = qr/(.*)\/(infografik\-kategorien)\/(.*)\/(?!.term)(.*)/mp;
my $subst = 'https://test.ixtract.de/infografik-kategorien/$3/?term=$3';
my $result = $str =~ s/$regex/$subst/rg;
print "The result of the substitution is' $result\n";
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html