Citreoviridin-¹³C₂3 is ¹³C labeled 2,3-Pentanedione (HY-W012998). 2,3-Pentanedione is a common constituent of synthetic flavorings and is used to impart a butter, strawberry, caramel, fruit, rum, or cheese flavor in beverages, ice cream, candy, baked goods, gelatins, and puddings. 2,3-Pentanedione also occurs naturally as a fermentation product in beer, wine, and yogurt and is releasedduring roasting of coffee beans^[1].