methyl ((2S)-1-((2S,4R)-2-(5-(10-chloro-6-ethyl-6H-benzo[5,6][1,3]oxazino[3,4-a]indol-3-yl)-1H-imidazol-2-yl)-4-fluoropyrrolidin-1-yl)-3-methyl-1-oxobutan-2-yl)carbamate