Synonyms: Butanoic acid, 2,3-dihydroxy-2-(1-methylethyl)-, (2,3,5,7a-tetrahydro- 1-hydroxy-1H-pyrrolizin-7-yl)methyl ester, [1S-[1alpha,7(2R*,3R*),7aal pha]]-;ECHINATINE;(2S,3S)-2,3-Dihydroxy-2-isopropylbutyric acid [(5R,6S)-6-hydroxy-1-azabicyclo[3.3.0]oct-3-en-4-yl]methyl;(2S,3S)-2,3-Dihydroxy-2-isopropylbutyric acid [(5R,6S)-6-hydroxy-1-azabicyclo[3.3.0]oct-3-en-4-yl]methyl ester