Preparation of (1R,8S)- and (1S,8R)-9-azabicyclo[6.2.0]dec-4-en-10-one: potential starting compounds for the synthesis of anatoxin-a
作者:Enikő Forró、Judit Árva、Ferenc Fülöp
DOI:10.1016/s0957-4166(01)00100-8
日期:2001.3
enriched ester 3a and alcohol 3b (e.e. ≥92%). Treatment of 3a and 3b with NH4OH/MeOH afforded the corresponding β-lactams (1R,8S)-2a and (1S,8R)-2b (e.e. ≥93%), potential starting compounds in anatoxin-a synthesis. The ring opening of lactams (±)-2, (±)-7, 3a and 3b, followed by reduction, resulted in racemic 4–6 and 8 and enantiomeric 4a, 4b, 5a and 5b eight-membered cyclic β-amino acid derivatives.
通过添加氯磺酰基异氰酸酯从环辛二烯获得的9-氮杂双环[6.2.0] dec-4-en-10-one(±)-2被N-羟甲基化成(±)-3,然后通过脂肪酶催化的不对称拆分(S)-成骨中心的一级羟基的酰化作用。高对映选择性(Ë当脂肪酶PS和丁酸乙烯酯在二-用于观察= 94)异-丙基醚在-15℃下,产生对映体富集酯3A和醇3B(EE≥92%)。用NH 4 OH / MeOH处理3a和3b得到相应的β-内酰胺(1 R,8 S)-2a和(1 S,8 R)-2b(ee≥93%),是抗毒素a合成中的潜在起始化合物。内酰胺的开环(±) - 2,(±) - 7,图3a和3b中,接着还原,导致外消旋4 - 6和8和对映体4A,4B,5A和5B中的八元环状β氨基酸衍生品。