A short and efficient total synthesis of (+)-madindolines A (1) and B (2), potent and selective inhibitors of interleukin 6, has been achieved. The synthesis features a key chelation-controlled 1,4-diastereoselective acylation to generate the quaternary carbon and an intramolecular acylation of allylsilane to build up the cyclopentene unit.
A research program is under way to develop a series of madindoline-based inhibitors targeting interleukin 6. Such inhibitors will have potential use in fighting a variety of diseases for which no effective therapeutic drugs currently exist. Madindoline is no longer available from natural Sources. Consequently, we have developed a purely synthetic route to ensure a supply of the compound. The synthesis of a range of analogues is described, all of which were evaluated for their inhibitory activity against the growth of IL-6-dependent 7TDI cells. From these assays, several synthetic madindoline analogues were identified as highly promising candidates for further development. (C) 2006 Published by Elsevier Ltd.
A short and efficient total synthesis of (+)-madindolines A (1) and B (2), potent and selective inhibitors of interleukin 6, has been achieved. The synthesis features a key chelation-controlled 1,4-diastereoselective acylation to generate the quaternary carbon and an intramolecular acylation of allylsilane to build up the cyclopentene unit.
Synthetic applications of a three-component Mannich reaction. Total synthesis of IL-6 inhibitor (+)-madindoline A and B
A three-component Mannichreaction of 3a-hydroxyfuroindoline (3), β-ketoester and formaldehyde was employed as an efficient and concise method to synthesize naturally-occurring (+)-Madindolines A (1) and B (2). The scope and limitations of the Mannichreaction with 3 are described.