$iblockID = 1; // ID инфоблока
$groupTendersID = 2; // ID привязанного элемента
$filter = ['IBLOCK_ID' => $iblockId, 'PROPERTY_49' => $groupTendersID]
$result = CIblockElement::GetList([], $filter, false, false, ['ID', 'IBLOCK_ID', 'NAME']);
while ($arElement = $result->GetNext()) {
echo $arElement['NAME'];
}