摘要
对confaione的d-生物素(1)全合成进行了改进,从半胱氨酸计算,总收率3.7%。5与4-溴代三苯膦丁酸甲酯进行Wittig-Schlosser缩合反应可立体专一性地转化成反式-烯(6)。以叠氮三甲基硅烷代替叠氮化锂亲核进攻9分子中C3-溴原子,可显著地提高顺式-叠氮内酰胺10的收率。
A modified stereospecific total synthesis of d-biotin
from L-(+)-cysteine based on Confalone’ s method was described,
Witting-Schlosser olefination of the aldehyde(5) with Witting reagent
derived from carbomethoxypropyl-triphenylphosphonium bromide ,after
acidic work-up,furnished transolefin(6 ) stereospecifically in 72%
yield.Treatment of the bromolactam(9) with azidotrimethylsilane
instead of lithium azide via SN2 nucleophilic substitution increased
the yield of cis azido lactam(10).The overall yield of d-biotin was
3.7%from cysteine.
出处
《药学学报》
CAS
CSCD
北大核心
1995年第11期824-830,共7页
Acta Pharmaceutica Sinica
关键词
维生素B
生物素
D-生物素
合成
立体专一性
d-Biotin
Witting-Schlosser reaction
SN2
nucleophilic substitution
Phase transfer catalysis