What if you have <> inside your tags? Text::Delimited can solve a lot of your problems for this kind of parsing. More info here.

#! usr/bin/perl

use strict;
use warnings;
use Text::Balanced qw/extract_bracketed/;

while( <DATA> ) {
  my $in = $_;
  print "\nIN : $in"; ## input
  my $out = $in;
  ## OK if you never have \<\> inside \<\>
  $out =~ s/\<([^\>]+)\>/\n\{$1\}\n/g;
  print "\tOUT 1 : $out"; ## simple output

  ## Have to be more clever if it does
  ## extract balanced delimiters
  my @extracted = extract_bracketed($in, '<>');
  if (!defined$extracted[0]){
    ## undefined if no balanced delimiters existed
    ## so print straight out
    print "\tOUT 2 : $in";
  }
  else {
    ## balanced delimters were found, 
    ## so process them as before
    print "\tOUT 2 : ";
    for (@extracted){
      s/^\<(.+)\>$/\n\{$1\}\n/g;
      print $_;
    }
  }
}


__DATA__
[SOUR]
Por Gisela Orozco 312.527.8461/ Chicago\
<line> Por Gisela Orozco< ttl>312.527.8461/ Chicago</ttl>
<<test>>extra bumphf
[download]

Will produce the right output more robustly (see the last input line) :

IN : [SOUR]
    OUT 1 : [SOUR]
    OUT 2 : [SOUR]

IN : Por Gisela Orozco 312.527.8461/ Chicago\
    OUT 1 : Por Gisela Orozco 312.527.8461/ Chicago\
    OUT 2 : Por Gisela Orozco 312.527.8461/ Chicago\

IN : <line> Por Gisela Orozco< ttl>312.527.8461/ Chicago</ttl>
    OUT 1 : 
{line}
 Por Gisela Orozco
{ ttl}
312.527.8461/ Chicago
{/ttl}

    OUT 2 : 
{line}
 Por Gisela Orozco< ttl>312.527.8461/ Chicago</ttl>

IN : <<test>>extra bumphf
    OUT 1 : 
{<test}
>extra bumphf
    OUT 2 : 
{<test>}
extra bumphf
[download]

HTH