作者:Thomas Burns、Madeleine Helliwell、Eric J. Thomas
DOI:10.1016/j.tetlet.2013.01.110
日期:2013.4
5-acylamino-3,8-diketo-ester, methyl (4R,5S,7S)-7-benzyloxy-4-[(S)-1-benzyloxyprop-2-yl]-5-methoxycarbonylamino-3,8-dioxododecanoate, cyclised via a stereoselective Mannich reaction to give an 8-azabicyclo[3.2.1]octanone. Hydrogenolysis of this with in situ acetal formation, reduction of the ester and a further cyclisation gave a lactam, (4R,5R,8S,9R,10S,12S,13S)-13-butyl-8-methyl-1-aza-6,14-dioxapentacyclo[8.3
在用酸处理时,开链的5-酰基氨基-3,8-二酮酯,甲基(4 R,5 S,7 S)-7-苄氧基-4-[(S)-1-苄氧基丙-2-经由立体选择性曼尼希反应环化的[yl] -5-甲氧羰基氨基-3,8-二氧十二烷酸酯,得到8-氮杂双环[3.2.1]庚酮。对其进行氢解并原位形成缩醛,还原酯并进一步环化,得到内酰胺,(4 R,5 R,8 S,9 R,10 S,12 S,13 S)-13-丁基-8-甲基-1-氮杂-6,14-二氧杂戊环[8.3.0.0 4,13 0 5,9 .1 5,12] tetradecan-2-one,对应于草铵苯五环的五环核。