Synthesis of Enantiomerically Pure Amino Acids Containing 2,5-Disubstituted THF Rings in the Molecular Backbone
作者:Anna Schrey、Frank Osterkamp、Alrun Straudi、Corry Rickert、Holger Wagner、Ulrich Koert、Bernhard Herrschaft、Klaus Harms
DOI:10.1002/(sici)1099-0690(199911)1999:11<2977::aid-ejoc2977>3.0.co;2-3
日期:1999.11
N- and C-protected derivatives of 2,5-disubstituted trans- and cis-THF amino acids 6 and 7 were prepared in enantiomerically pure form from L-alanine. Felkin–Anh-controlled reduction of the ketone 9 was achieved with a 85:15 diastereoselectivity. Epoxidation of 10 and subsequent intramolecular epoxide opening gave the trans- and cis-THF alcohols 11 and 12, which were further transformed into the corresponding
ñ -和C ^ -保护的衍生物2,5-二取代反式-和顺-THF氨基酸6和7中,从L-丙氨酸对映体纯形式制备。用Felkin-Anh控制的酮9的还原反应非对映选择性为85:15。环氧化反应的10和随后的分子内环氧化物开环得到反式-和顺-THF醇11和12,这是进一步转化为相应的Ñ -和C ^ -保护的2,5-二取代反式-和顺式-THF氨基酸。构象研究表明,顺式-THF二酰胺34在固态和CDCl 3溶液中为β-转弯模拟物。