Robuta

https://www.ncbi.nlm.nih.gov/Structure/pdb/1FM7 1FM7: CHALCONE ISOMERASE COMPLEXED WITH 5-DEOXYFLAVANONE CHALCONE-FLAVONONE ISOMERASE 17-HYDROXY-2-(4-HYDROXY-PHENYL)-CHROMAN-4-ONESULFATE ION