The flavor of “cola” (not just Coca Cola, but also Pepsi and generics) is actually a “fantasia” blend of vanilla, cinnamon (or cassia) and citrus oil, plus unspecified “pther”. I found that the flavored mead at Midnight Meadert that has vanilla and cinnamon flavors added tastes amazingly like Coke. So there is certainly a Coca Cola -tasting drink without carbonation.
And both Spoiler Virgin and jaycat are correct. Icees and Slurpees and such “frozen” drinks have long been available in “Coke” or “Cola” flavor (without carbonation), and “Coke syrup” used to be widely used for various upset stomach ailments. Back when pharmacies still operated soda fountains, you could get it direct from them (my father got it for me once). And drug stores actually sold bottled “coke syrup” as well. In fact, they still do:
We discussed this on this Board almost twenty years ago: