ChemInform Abstract: Synthesis and Conformational Analysis of the Multidrug Resistance- Reversing Agent Hapalosin (XIIIa) and Its Non-N-methyl Analogue (XIIIb) .

✍ Scribed by T. Q. DINH; X. DU; R. W. ARMSTRONG

• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 40 KB
• Volume: 28
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199706193

✦ Synopsis

Synthesis and Conformational Analysis of the Multidrug Resistance-Reversing Agent Hapalosin (XIIIa) and Its Non-N-methyl Analogue (XIIIb) .

-The key steps in the synthesis of (XIIIa) include two Brown allylboration reactions to obtain the chiral precursors (II) and (V) and macrolactonization of the hydroxy acid obtained from (XII), as well as in the synthesis of (XIIIb) the chelation-controlled reduction of (XIV) and cycloamidation of the amino acid obtained from (XVI). In CDCl3 at 25 • C, synthetic hapalosin (XIIIa) exists as a 2.3:1-mixture of conformers, while (XIIIb) exists only as a single conformer. -(DINH, T.