(3R,3aR,15S)-3-(4-hydroxy-3-methoxyphenyl)-3,3a,6,7,8,9,10,11,12,13,14,15-dodecahydro-4H-1,16-etheno-5,15-(propanoiminoethano)furo[3,4-l][1,5,10]triazacyclohexadecine-4,21-dione