从生物来源的试剂中获得的二氢呋喃[2,3 - f ]吲哚齐酮即使在数克级也被用作具有多达五个化学多样化点的高级构件。这导致了一系列单、二和四羟基呋喃中氮茚的连续合成,这些产品属于非常稀有和精细的四氢呋喃稠合中氮茚家族,具有多达六个受控的立体中心。这些序列包括,除其他外,非对映选择性烯烃环氧化、立体选择性环氧化物开环成四氢呋喃反式二醇、它们作为酯或丙酮化物的保护,以及内酰胺羰基还原,最后是乙酸酯或丙酮化物脱保护。
The furo[2,3(or 3,2)-f]indolizidinediones 4a,b were synthesized in five steps from glutamic acid in good yield. The ketones were converted into trans alcohols 5a,b or oximes 6a,b (either as syn-anti mixture or as single isomer). The selectivity of these reactions is discussed.
A concise and very efficient route to enantiopure tetrahydrofuran-fused indolizidinols, which could be considered as protected new indolizidindiols, is described in two-steps sequence starting from the known furoindolizidindiones. The key-step of these transformations was the formation, in one operation, of THF indolizidinols containing a lactam function by simultaneous highly diastereoseleclive catalytic hydrogenation of the carbonyl function and the furan ring. During these investigations, numerous catalysts in different combinations were tested and the impact of substrates on the reduction profile is discussed. (C) 2008 Elsevier Ltd. All rights reserved.
Synthesis and sequential diastereoselective incorporation of hydroxyl groups into hexahydrofuro[3,2-<i>f</i>]indolizin-7(2<i>H</i>)-one to give mono-, di- and tetra-hydroxyfuroindolizidines
3-f]indolizidinone obtained from biosourced reagents even at multigram-scale was used as an advanced building-block with up to five points of chemical diversification. This resulted in the sequential synthesis of a series of mono-, di- and tetra-hydroxyfuranoindolizidines belonging to a very scarce and elaborate tetrahydrofuran-fused indolizidine family with up to six controlled stereogenic centers. These sequences
从生物来源的试剂中获得的二氢呋喃[2,3 - f ]吲哚齐酮即使在数克级也被用作具有多达五个化学多样化点的高级构件。这导致了一系列单、二和四羟基呋喃中氮茚的连续合成,这些产品属于非常稀有和精细的四氢呋喃稠合中氮茚家族,具有多达六个受控的立体中心。这些序列包括,除其他外,非对映选择性烯烃环氧化、立体选择性环氧化物开环成四氢呋喃反式二醇、它们作为酯或丙酮化物的保护,以及内酰胺羰基还原,最后是乙酸酯或丙酮化物脱保护。