Synthese von (1α,7α,8β)-(±)-7-hydroxy-1-(hydroxymethyl)pyrrolizidin, der Necin-Base rac-Platynecin

Synthesis of (1α,7α,8β)-(±)-7-Hydroxy-1-(hydroxymethyl)pyrrolizidin, the Necine rac-Platynecine rac-Platynecine (rac-7) can easily be obtained in high yields from diethyl (±)-cis-2,3-pyrrolidinedicarboxylate (rac-1) by N-alkylation to ethyl (±)-cis-2,3-bis(ethoxycarbonyl)-1-pyrrolidinepropionate (rac-2), Dieckmann reaction to ethyl (1α,8β)-(±)-6-ethoxycarbonyl-7-oxo-1-pyrrolizidinecarboxylate (rac-3), subsequent saponification, decarboxylation, reduction to (1α,7α,8β)-(±)-pyrrolizidine-1,7-carbolactone (rac-6), and further reduction to the desired title compound rac-7.