How to get value from string javascript?

Question

I have this string

var a = toNormal("sdf45sdf4sdf45sd4f5s4df"),
b = toNormal("fg45df4g5dfg5df"),
c = toNormal("s5d4f5sd4fsdfdd5c");
... other code

how to get "sdf45sdf4sdf45sd4f5s4df", "fg45df4g5dfg5df" and "s5d4f5sd4fsdfdd5c"?

my try

$pattern = '/a = toNormal("(.*)");/';
preg_match($pattern, $html, $matches);