I recommend reading perlrequick and perlretut to gather some insight on how regular expressions work.

Nevertheless, here's a possible implementation: 

my $re = qr/(?:a|b)h/;

print 'abcdef' !~ $re;
print 'ahcdef' !~ $re;
print 'abbhef  !~ $re;

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yields 
1
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In reply to Re: RegEx: How to negate more than one character? by shigetsu
in thread RegEx: How to negate more than one character? by lokiloki

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