α-ketoglutarate

(S)-4-Amino-5-((1S,5R,7R)-10,10-dimethyl-3,3-dioxo-3λ6-thia-4-aza-tricyclo[5.2.1.01,5]dec-4-yl)-5-oxo-pentanoic acid ethyl ester

(5S)-5-(5-methyl-2,7,8-trioxabicyclo[3.2.1]octan-1-yl)pyrrolidin-2-one

(5S)-1-tert-butoxycarbonyl-5-(5-methyl-2,7,8-trioxabicyclo[3.2.1]oct-1-yl)-2-pyrrolidone

(+/-)-endo-3a,4,7,7a-tetrahydro-1H-4,7-methanoinden-1-one