my @phrases = ( 'kinase i', 'hib', 'tor', 'tor SET6', 'SET6', 'p16(INK4A)', 'cell', 'MAP', 'H1 inhibitor' );
my $sentence='kinase inhibitor SET6 MAP H1 inhibitor activates p16(INK4A) in cell-wall';

for (my $i=0;$i<=$#phrases;$i++) {
	$phrases[$i]=~s/\s+/  /g;
}
my $phrases_re = join '|', map { quotemeta } @phrases;

$sentence=~s/\s+/  /g; $sentence=' '.$sentence.' ';
$sentence =~ s/\s($phrases_re)\s/ \#$1\# /g; $sentence=~s/\s+/ /g; $sentence =~ s/^\s+|\s+$//g;

print "$sentence\n";

#Output: 'kinase inhibitor #SET6# #MAP# #H1 inhibitor# activates #p16(INK4A)# in cell-wall'