You can use the following tricks. Take abs or square  the function then call optmodel procedure.

proc optmodel;
   var x ;

   min q=abs((x-1)*(x-2));
   con c1: x<=2;
   solve;
   print x;
   quit;

proc optmodel;
   var x ;

   min q=((x+1)*(x-2)) **2;
   con c1: -5<=x<=1;
   solve;
   print x;
   quit;

谢谢！