I run this substitution command on Ubuntu 12.04.
$ sed -e \"s/([a-zA-Z0-9.-/\\\\ :]+)/\\1/g\"
However, the following error is raised.
You can solve it in two ways. One of them is to use -r switch to avoid escaping special characters and move - in the range to first or last position and avoid its special meaning, it would be like:
sed -re "s/([a-zA-Z0-9./\\ :-]+)/\1/g"
Otherwise you will need to escape either (, ) and +, like:
sed -e "s/\([a-zA-Z0-9./\\ :-]\+\)/\1/g"