If frame in movieclip = 375, then in the main scene to frame 37

[sfinksred]

Hey guys
I really looked for this everywhere, I tried in every way by myself, but of course didn't work.
Using AS2
So basically, I would like to have something like this:

if
frame INSIDE movieclip_mc = 375
then
gotoAndPlay in the MainScene frame 37

I also thought about putting a code on this 375 frame of movieclip, which would like smth like this:

_root.gotoandplay("MainScene",37);

but it also didnt work.

If you can help, pleae do, as it is my coursework =)

Many thanks.