As @T.J.L. mentioned, the only canon appearances of the initially highly-classified Prometheus-type vessels were in:
Unfortunately, none of these involve battle during the Dominion War. However, the last instance is particularly interesting because it indicates that the Prometheus class survived canonically into the 26th Century and served in the most pivotal battle of the Time Wars, suggesting the overall success of the Prometheus design.
The Prometheus class has made several notable appearances in Star Trek's extended universe, including Star Trek Online ("Welcome to Earth Spacedock").
The appearances that are most relevant to the question are:
After the safe return of the Prometheus and the testing of the ship's multi-vector assault mode were completed, Starfleet had rushed the construction of two further vessels, the USS Cerberus and USS Heracles. Both of these vessels were in service by late 2375, and the Cerberus served as Admiral William Ross' flagship from 2376 to 2379. (From novels DS9: Avatar and TNG: A Time for War, A Time for Peace.)
As the Dominion War ended in 2375, the timing above suggests that two Prometheus-class vessels may have seen action in the last few months of the war.