In the cases you've shown, there's whitespace enclosing the text you want, so you can use a lookbehind and lookahead to capaure the enclosed text:

use warnings;
use strict;

while (<DATA>) {
    print "$1\n" if /(?<=\s)([a-z\s]+)(?=\s)/i;

}

__DATA__
1) some text 2)
1. some text 2.
1) some text 2.
1. 2.10.10.20 some text 2.
1) 2.10.10.20 2)

[download]

Output:

some text
some text
some text
some text

[download]

Hope this helps!

In reply to Re: regular expression for getting text between 1. and 2. by Kenosis
in thread regular expression for getting text between 1. and 2. by Anonymous Monk

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