#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;
use File::Basename;

my %filenames;
my @files = map{[basename($_),(split /\./,basename($_))[0,5]]}glob "$pfad*Filter*.Endung";
my @allowed_strings = qw(AB12 CD34);

for my $file(@files){
     my @same_jobs = grep{$_->[1] eq $file->[1] and $file->[0] ne $_->[0]}@files;
     @filenames{@same_jobs} = ();
}

print Dumper([keys %filenames]);