[рони]

var str = '(#24174#||#22301#||#22298#||#22303#) && #14827# && #14543#'
   reg = /(^|[^#]+)\(.*?\)$|\(.*?\)[^#]+/
   str = str.replace(reg,'');
   alert(str);
   str = '#144357# && #14827# && (#24174#||#22301#||#22298#)';
   str = str.replace(reg,'');
   alert(str);
   str = '(#24174#||#22301#||#22298#||#22303#)';
   str = str.replace(reg,'');
   alert(str);