A convenient allylsilane-N-acyliminium route toward indolizidine and quinolizidine alkaloids
1UMR 6504, CNRS Université Blaise Pascal (Clermont-Fd), 63177 Aubière Cédex, France. Roland.REMUSON@univ-bpclermont.fr
Abstract:
This review relates all the results that we obtained in the field of the total synthesis of indolizidine and quinolizidine alkaloids using a strategy of the addition of an allylsilane on an N-acyliminium ion. In this paper, we describe the synthesis of racemic indolizidine 167B and chiral indolizidines: (-)-indolizidines 167B, 195B, 223AB, (+)-monomorine, (-)-(3R,5S,8aS)-3-butyl-5-propylindolizidine and (-)-dendroprimine. Next, we relate the synthesis that we have developed in the quinolizidines field: (+/-)-myrtine and epimyrtine, (+/-)-lasubines I and II and chiral quinolizidines: (+)-myrtine, (-)-epimyrtine, (-)-lasubines I and II and (+)-subcosine II.
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