Your Science Minister has convinced you to go to a party being thrown by Frieden-und Freudenland’s leading scientists to celebrate the successful synthesises of a new element at Civitas Pacis University. The element itself decays within microseconds, but that hasn’t stopped the party from dragging on for hours. Your attention has finally been sparked as a massive debate over the name of the element has broken out. The situation threatens to become as unstable as the element itself, and people are looking to you for a solution.
It is definitely a noun here. I think it should have been a singular noun: "synthesis."