کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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5218426 | 1383327 | 2013 | 9 صفحه PDF | دانلود رایگان |

The most efficient and concise asymmetric synthesis of (â)-(1R,7aS)-absouline to date, which was accomplished in eight steps and 20% overall yield from commercially available starting materials, is described. The doubly diastereoselective conjugate addition of lithium (S)-N-benzyl-N-(α-methylbenzyl)-amide to an enantiopure α,β-unsaturated ester derived from l-proline was employed as the key step. Subsequent hydrogenolytic N-debenzylation and acid-promoted cyclisation of the resultant β-amino ester produced the 1-aminopyrrolizidin-3-one scaffold, then reduction with DIBAL-H was followed by DCC-mediated coupling with (E)-p-methoxycinnamic acid to complete the synthesis of (â)-(1R,7aS)-absouline.
The asymmetric synthesis of (â)-(1R,7aS)-absouline was accomplished in eight steps and 20% overall yield from commercially available starting materials by employing the doubly diastereoselective conjugate addition of lithium (S)-N-benzyl-N-(α-methylbenzyl)amide to an enantiopure α,β-unsaturated ester derived from l-proline as the key step.
Journal: Tetrahedron - Volume 69, Issue 4, 28 January 2013, Pages 1369-1377