';' expected. Insert a semicolon at the end. already one there?

saying that its expecting one within the code but i cant find it as im still very new to javascript so can someone help me find the problem.

#pragma strict
var Level1=true;
var Level2=true;
var Back=true;

function OnMouseEnter(){
   renderer.material.color=Color.red;
   }
   
function OnMouseExit(){
   renderer.material.color=Color.white;
   }
   
function OnMouseDown(){

   if(Level1==true){
   Application.LoadLevel(0);
   }
   
   else if(Level2==true){
   Application.LoadLevel(0);
   }
   
   else(Back==true){
   Application.LoadLevel(1);
   }
}

else(Back==true){
Application.LoadLevel(1);
}

Are parenthesis after an “else” statement even allowed in Javascript/UnityScript? Perhaps that is the problem.