Department of Chemistry, University of Kalyani, Kalyani-741235, West Bengal, India.
J Org Chem. 2012 Dec 21;77(24):11056-63. doi: 10.1021/jo3019329. Epub 2012 Dec 11.
A diastereodivergent preparation of two N-alkenylnitrones (9 and 11) from easily available (R)-2,3-O-cyclohexylideneglyceraldehyde (5) led to an enantiodivergent synthesis of both enantiomers of the dendrobate alkaloid 241D in a sequential two-directional approach involving intramolecular nitrone cycloaddition as the key step. Either of these two nitrones could, in principle, be utilized for the preparation of the title compounds in an enantioconvergent fashion as well. The methodology was extended to prepare an analogue (33) of (-)-241D.
从易得的(R)-2,3-O-环己基亚基甘油醛(5)出发，通过非对映选择性的方法制备了两种 N-烯基硝酮(9 和 11)，这种方法为涉及分子内环加成反应作为关键步骤的、对映选择性的、顺序双向的合成方法提供了一种简洁的方式，用于制备同时具有两种对映异构体的齿果草生物碱 241D。这两种硝酮原则上都可以用于以对映体转化的方式来制备标题化合物。该方法被扩展用于制备(-)-241D 的类似物(33)。
