You seem to be mixing backquote (`) and single quote ('). These are NOT the same.
Normally, `$nnn` is used to run a var as a cmd (old school style). The modern idiom in bash is
$($nnn)
instead.
Note tha tin both cases, it runs in a sub-shell; see links below.
Single quotes are used to stop bash interpolating values that look like vars eg
'$fred'
is seen as just fred, whereas double quotes "$fred" would allow bash to interpret the $ sigil as the beginning of a var named fred.
See
http://rute.2038bug.com/index.html.gz http://tldp.org/LDP/Bash-Beginners-G...tml/index.html http://www.tldp.org/LDP/abs/html/
Incidentally, escaping means putting the \ just before the char in qn. Eg \` means a literal backquote.
Adding one after the backquote has zero effect on the backquote.
HTH