(1R,2S,8R,9S)-5-methyl-3,5,7-triazapentacyclo[7.4.4.22,8.01,9.03,7]nonadeca-10,12,18-triene-4,6-dione 、
4-甲基-1,2,4-三吖啉-3,5-二酮 以
二氯甲烷 为溶剂,
以71%的产率得到(4R,4aS,5R,9S,9aR,10S)-2,7-dimethyl-1,3,6,8-tetramethylene-2,3,3a,4,5a,6,7,8,8a,9,10,10a-dodecahydro-1H,5H-4a,9a-butano-4,10:5,9-diethenodicyclopenta[b,g]naphthalene