Total Syntheses of (+-)-Cryptopleurine,(+-)-Antofine and (+-)-Deoxypergularinine

摘要

The alkaloids (+-)-cryptopleurine 1, (+-)-deoxygergularinine 3 were synthesized by Pictet-Spengler cyclization of the 2-arylmethylpiperidine and -pyrrolidines 4,5 and 6 obtained by sequential N-deprotection-reduction of the parent enecarbamates 7,8 and 9. These latter were made by the Horner reaction of phosphorylated carbamates 12 and 13 with the appropriate aldehydes 10 and 11.