Ìyípo yìí jẹ́  ipóyì ìbáṣepọ̀ kẹ́míkà àgọ́ ara àkọ́kọ́ tí wọ́n máa kọ́kọ́ ṣàwárí (Hans Krebs àti Kurt Hensele, 1932), ní ọdún marún sẹ́yìn kí wọ́n tó ṣàwárí ìyípo TCA.. 