You should use $1 instead of \1 in the substitution. < and > are not magical in regexen and, apart from $, there are no magical characters in the substitution string in any case - you do not need to escape < and >. Perl allows you to use different delimiters for regexes which can often make the regex much easier to read. Consider:

$text =~ s!(\bS\.(?=\s))!<$1=initial>!g;

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Perl reduces RSI - it saves typing

In reply to Re^3: Regex is eating up whitespace by GrandFather
in thread Regex is eating up whitespace by gatito

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