let
Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
#"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", type text}, {"Column2", type text}, {"Column3", type text}, {"Column4", type text}, {"Column5", type text}}),
#"Unpivoted Columns" = Table.UnpivotOtherColumns(#"Changed Type", {"Column1"}, "Attribute", "Value"),
#"Removed Columns" = Table.RemoveColumns(#"Unpivoted Columns",{"Attribute"})
in
#"Removed Columns"
If it's a later version then you could easily do this using Power Query/Get and Transform, otherwise you would probably be best with code.
PS I'm assuming A1, B1, C1 etc are all in separate cells.