A Divergent and Stereoselective Approach for the Syntheses of Some Polyhydroxylated Indolizidine and Pyrrolizidine Iminosugars

作者：Rajender Anugula; Rao Jalagam Prasada; Rao Batchu Venkateswara^*

来源：European Journal of Organic Chemistry, 2013, 2013(9): 1749-1757.

DOI：10.1002/ejoc.201201342

• Natural products
• Azasugars
• Nitrogen heterocycles
• Total synthesis
• Diastereoselectivity

A common, divergent, and efficient approach to the syntheses of (+)-steviamine (9), (-)-1-deoxy-8a-epi-castanospermine (10), (+)-trihydroxyindolizidine (11), (+)-3,7a-di-epi-hyacinthacine A1 (12), and (-)-2-epi-lentiginosine (4) was achieved by starting from D-ribose-derived intermediate 13. The key steps involved in these syntheses are a highly diasteroselective Grignard addition to a ribosylimine, a onepot stereoselective intramolecular reductive amination, a selectve deprotection of a silyl ether, and a ring-closing metathesis (RCM) reaction.

• 出版日期2013-3