73 リパーゼを利用するキラルγ-ブチロラクトンの合成法の開発とその天然物合成への応用(ポスター発表の部)

抄録

Enzymes are now recognized as substrate-specific and highly enantioselective catalyst for asymmetric synthesis. In particular, lipases have recently been used for biocatalytic resolutions on the basis of the admission of organic solvents as reaction media. We succeeded immobilized lipase-mediated resolution of N,N-dialkyl〜3-hydroxy-4-pentenamides (1 and 2), unsuccessful in resolution by the Katsuki-Sharpless asymmetric epoxidation. Iodolactonizaion of the homochiral 1 and oxy-lactonization of the homochiral 6 proceeded stereoselectively, affording cis-3,4-disubstituted γ-lactones (11 and ent-11) and trans-3,4-disubstituted γ-lactones (8 and ent-8) preferentially, respectively. These γ-lactones have been used as chiral building blocks for the synthesis of biological active compounds such as trans-wisky and cognac lactones, litsenolides, (+)-blastimycinone, NFX-2, NFX-4, metabolites from Gorgonian Plexaura flava, and muscarine.