SELECT 
  product_prices.product_id, 
  MIN(
    IF(
      product_prices.percentage_discount = 0, 
      product_prices.price, 
      product_prices.price - (
        product_prices.price * product_prices.percentage_discount
      )/ 100
    )
  ) AS price 
FROM 
  product_prices 
WHERE 
  product_prices.product_id IN (
    276551, 276583, 279115, 279095, 276805, 
    276567, 276811, 276584, 276574, 276560, 
    276580, 276566, 279097, 276812, 276815, 
    276803, 276804, 279104, 279255, 276577, 
    279262, 279250, 283189, 287048
  ) 
  AND product_prices.lower_limit = 1 
  AND product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  product_prices.product_id

Query time 0.00160

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "20.84"
    },
    "grouping_operation": {
      "using_filesort": false,
      "table": {
        "table_name": "product_prices",
        "access_type": "range",
        "possible_keys": [
          "usergroup",
          "product_id",
          "lower_limit",
          "usergroup_id"
        ],
        "key": "product_id",
        "used_key_parts": [
          "product_id"
        ],
        "key_length": "3",
        "rows_examined_per_scan": 24,
        "rows_produced_per_join": 2,
        "filtered": "10.00",
        "index_condition": "(`goimagine`.`product_prices`.`product_id` in (276551,276583,279115,279095,276805,276567,276811,276584,276574,276560,276580,276566,279097,276812,276815,276803,276804,279104,279255,276577,279262,279250,283189,287048))",
        "cost_info": {
          "read_cost": "20.60",
          "eval_cost": "0.24",
          "prefix_cost": "20.84",
          "data_read_per_join": "57"
        },
        "used_columns": [
          "id",
          "product_id",
          "price",
          "percentage_discount",
          "lower_limit",
          "usergroup_id"
        ],
        "attached_condition": "((`goimagine`.`product_prices`.`lower_limit` = 1) and (`goimagine`.`product_prices`.`usergroup_id` in (0,1)))"
      }
    }
  }
}

Result

product_id price
276551 7.00000000
276560 7.00000000
276566 7.00000000
276567 7.00000000
276574 7.00000000
276577 7.00000000
276580 7.00000000
276583 112.00000000
276584 93.00000000
276803 7.00000000
276804 7.00000000
276805 7.00000000
276811 7.00000000
276812 5.00000000
276815 7.00000000
279095 7.00000000
279097 7.00000000
279104 7.00000000
279115 45.00000000
279250 35.00000000
279255 35.00000000
279262 35.00000000
283189 25.00000000
287048 120.00000000