Stereoselective syntheses of solenopsin A and B

✍ Scribed by Yasushi Matsmura; Keiji Maruoka; Hisashi Yamamoto

• Book ID: 104220723
• Publisher: Elsevier Science
• Year: 1982
• Tongue: French
• Weight: 246 KB
• Volume: 23
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)87224-x

✦ Synopsis

Effective and convenient syntheses of solenopsin A and B have been developed which involve the Beckmann rearrangement-alkylation reaction promoted by organoaluminum reagents and a new stereoselective reduction of imino functional group. The recent discovery of the aluminum method for the direct synthesis of o-alkylated amines from the simple oxime sulfonate (eq. 1) has substantially simplified the task of the synthesis in this area. 1 Thus, the method should be especially useful in the field of alkaloid synthesis: for example, it provides a simple approach to the structure of 2,6-dialkylated piperidines from o-alkylcyclopentanones. Solenopsin A (i) and B (z), naturally occuring piperidine alkaloids isolated from the venom of the fire ant, Solenopsis savissima, 2 are members of these class of compounds which exhibit pronounced hemolytic, 3 insecticidal, and antibiotic4 activity. As far as we know there were no known synthetic methods capable of generating stereospecifically m-2,6-disubstituted piperidine structure, characteristic of 1 and 2. 5 This fact, together with the occurrence of the same structural unit in other natural products, 6 led us to study the stereospecific route to solenopsin A and B.