Amide functional groups play a significant role in a variety of areas such as medicinal drugs. Therefore, the efficient synthesis of amide bonds has received much attention by organic chemists, making this one of the most reliable reactions in synthetic organic chemistry. On the other hand, functionalization of the generated amide groups is less explored than their construction due to the high stability of amide carbonyls. Our group has been working on development of practical transformations of amides, and application to total synthesis of complex natural products.
1-1. Reactivity Control of Amides Using Alkoxy Group
1-2. Unified Total Synthesis of Stemoamide-type Alkaloids
1-3. Amides as 1,3-Dipole Equivalents
Skipped diene is a widely distributed functional group in biologically active natural products. However, the synthesis is not trivial due to the difficulty in the control of its stereochemistry. We are actively working on development of practical methods to construct the skipped dienes, and application to total synthesis of natural products.
All-nitrogenated sugars (ANSs) are anticipated to be privileged structures with useful biological activities. However, ANS synthesis has been challenging due to the difficulty in the installation of multi-amino groups. We developed a concise synthetic route to peracetylated ANSs in seven steps from commercially available monosaccharides. The key to success is the use of the sequential Overman rearrangement, which enables formal simultaneous substitution of four or five hydroxy groups in monosaccharides with amino groups.