use strict;
use warnings;

my $regex = '\{\[%tqu.*]}';
my $subst = '';

while(my $line = <DATA>) 
{
	$line =~ s/$regex/$subst/gi;
	print $line."\n";
}

__DATA__
1. Ka6 ({Of course not} 1. b6 $2 Kb7 $11) 1... Kb8 (1... f4 2. b6 $18) {[%tqu "What is  White's next move?","","",g3,"",0,b6,"misses the win:",0]} 2. g3 $1 13. g6 c3