#!/usr/bin/perl
use strict;
use warnings;

use Data::Dumper;

my $text = "Vorrede bla bla Anfang <<A>> Teil1 <<A>> Teil2 <<B>> Teil3 <<A>> Ende Nachrede.";
my $re   = qr~Anfang <<A>> [^<]+ (<<A>>) [^<]+ (<<B>>) [^<]+ <<A>> Ende~;
print "text    : [$text]\n",
      "re      : [$re]\n";

my @allmatch = $text =~ $re;
my ($m1, $m2, $m3) = ($`, $&, $');

print "allmatch: ", Dumper \@allmatch;
print "m1      : [$m1]\n",
      "m2      : [$m2]\n",
      "m2      : [$m3]\n";