Pyrol or Pyrrol: How To spell?

The word Pyrol is misspelled against Pyrrol, a noun meaning "A nitrogenous base found in coal tar, bone oil, and other distillates of organic substances, and also produced synthetically as a colorless liquid, C4H5N, having on odor like that of chloroform. It is the nucleus and origin of a large number of derivatives. So called because it colors a splinter of wood moistened with hydrochloric acid a deep red."