Bupropion Hydrochloride (Wellbutrin) is classified as an antidepressant.
Buspirone Hydrochloride (BuSpar) is classified as an antianxiety agent.
In all honesty, I don't know if the similarity in name makes them related or not. To find the correct answer, call your local pharmacist who will gladly answer this for you.
Peace
Greenlydia