Synthesis of 5-Substituted 5-Hydroxy-2-pyrrolidones, Metabolites of the Antipsychotic Benzamide Remoxipride.
作者:Lars Gawell、Curt-Eric Hagberg、Thomas Högberg、Marianne Widman、Kjell Ankner、Ulf Junggren、Bo Lamm、Peter Nordberg、Magnus Erickson、Inger Grundevik、Inger Hagin、Kurt-Jürgen Hoffman、Svante Johansson、Sam Larsson、Ingalil Löfberg、Kristina Ohlson、Björn Persson、Inger Skånberg、Lija Tekenbergs-Hjelte
DOI:10.3891/acta.chem.scand.43-0476
日期:——
This paper describes the synthesis of 5-[(3-bromo-2,6-dimethoxybenzamido)-methyl]-5-hydroxy-2-pyrrolidon e (3) and its 1-ethyl analogue 2, two urinary metabolites of the dopamine D-2 antagonist remoxipride [1, (S)-3-bromo-N-[(1-ethyl-2-pyrrolidinyl)methyl]-2, 6-dimethoxybenzamide]. Two synthetic schemes leading to a common intermediate, 5-benzamido-4-oxopentanoic acid 4, were developed. This key intermediate permits conversion into either metabolite. Reaction of 4 with isobutyl chloroformate furnished a mixed carbonic anhydride, which upon treatment with ethylamine or ammonia gave the 4-oxopentanamides 5 and 6, respectively. Ring-closure afforded the corresponding 5-hydroxy-2-pyrrolidones 2 and 3.