The Antares-class name has been given to various ships and designs used by Corvallens, Bajorans, and Starfleet. What's more confusing is that the design changes each time, but is still used as a freighter. The Bajoran ship in The Next Generation episode "Ensign Ro" is called Antares-class, and was reused in Deep Space Nine. The Corvellian Antares is a reuse of the Straleb ship in TNG episode "The Outrageous Okona." Kasidy Yates freighter, the Xhosa is also listed as an Antares-class cargo freighter.

It's unclear, and unlikely, that the USS Antares NCC-501 from TOS is of the same design as the USS Hermes NCC-10376 and so has been moved to the Unknown-class page. It's also possible that the Starfleet Antares is different than the civilian version.

Related Links:
The Antares Class(es)(EAS).

USS Hermes NCC-10376
   Served in Captain Picard's blockade during the Klingon Civil War in 2368.
   "Redemption" - TNG.