var $topMenu = $('#menu_print_razdel'),
$menuItems = $topMenu.find('a[rel]'),
$mainLeft = $('.nav-header.active').find('a[rel]');
function scroll(){
// тут получаем id
.....
$menuItems
.removeClass('active')
.filter('[rel='+id+']').addClass('active');
$mainLeft
.removeClass('active')
.filter('[rel='+id+']').addClass('active');
......
}