SELECT 
  cscart_product_prices.product_id, 
  MIN(
    IF(
      cscart_product_prices.percentage_discount = 0, 
      cscart_product_prices.price, 
      cscart_product_prices.price - (
        cscart_product_prices.price * cscart_product_prices.percentage_discount
      )/ 100
    )
  ) AS price 
FROM 
  cscart_product_prices 
WHERE 
  cscart_product_prices.product_id IN (
    411736, 410485, 443778, 413186, 406992, 
    417005, 421337, 459209, 418678, 450452, 
    428056, 452645
  ) 
  AND cscart_product_prices.lower_limit = 1 
  AND cscart_product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  cscart_product_prices.product_id

Query time 0.00072

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.050171963,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_product_prices",
          "access_type": "range",
          "possible_keys": [
            "usergroup",
            "product_id",
            "lower_limit",
            "usergroup_id"
          ],
          "key": "usergroup",
          "key_length": "9",
          "used_key_parts": ["product_id", "usergroup_id", "lower_limit"],
          "loops": 1,
          "rows": 24,
          "cost": 0.04252208,
          "filtered": 50,
          "attached_condition": "cscart_product_prices.lower_limit = 1 and cscart_product_prices.product_id in (411736,410485,443778,413186,406992,417005,421337,459209,418678,450452,428056,452645) and cscart_product_prices.usergroup_id in (0,1)"
        }
      }
    ]
  }
}

Result

product_id price
406992 319.54000000
410485 118.68000000
411736 1437.16000000
413186 178.75000000
417005 1472.16000000
418678 1703.47000000
421337 1784.18000000
428056 459.53000000
443778 1210.72000000
450452 1729.01000000
452645 601.84000000
459209 780.05000000