Mexican Coke, often distinguished by its use of cane sugar instead of high-fructose corn syrup, contains carbonated water, sugar, caramel color, phosphoric acid, natural flavors, and caffeine. 
Here's a more detailed breakdown:
Natural Flavors: These are the ingredients that give the drink its distinctive cola taste. 
Caffeine: This is a stimulant that is added to the beverage. 
Carbonated Water: The base of the beverage, providing the fizz. 
Sugar: Mexican Coke uses cane sugar, which is a natural sweetener, as opposed to the high-fructose corn syrup used in American Coke. 
Caramel Color: This ingredient gives the drink its characteristic brown color. 
Phosphoric Acid: This is an acidity regulator, contributing to the drink's tartness.