(R)-1-((2S,3R)-1-(buta-2,3-dien-1-yl)-3-methoxy-4-oxoazetidin-2-yl)-2-methylbuta-2,3-dien-1-yl acetate

(8R,9R)-7,9-dimethoxy-6-methyl-4,5-dimethylene-1-azabicyclo[6.2.0]dec-6-en-10-one

(3R,4S)-1-(buta-2,3-dien-1-yl)-4-((S)-1-hydroxy-2-methylbuta-2,3-dien-1-yl)-3-methoxyazetidin-2-one

(3R,4S)-1-(buta-2,3-dien-1-yl)-4-((R)-1-hydroxy-2-methylbuta-2,3-dien-1-yl)-3-methoxyazetidin-2-one