Nitrogen sulfide (S4N4) was an inorganic compound that could be found in planetary atmospheres.
An inhabited planet located a few light years from Qo'noS (or Klingon space) had an atmosphere consisting of nitrogen sulfide. Following their mission that left them departing Qo'noS in 2151, the crew of Enterprise NX-01 planned to visit the planet to begin their mission of exploration, with the expectations of finding non-humanoid life. (ENT: "Broken Bow")