Trichotomine

(5S)-2-[(5S,2E)-5-Carboxy-6,11-dihydro-3-oxo-3H-indolizino[8,7-b]indol-2(5H)-ylidene]-2,5,6,11-tetrahydro-3-oxo-3H-indolizino[8,7-b]indole-5-carboxylic acid