23 グリシノエクレピンAの合成研究

概要

論文の詳細を見る
We recently reported the isolation and structure elucidation of glycinoeclepin A (1), which is a natural hatching stimulus for the soybean cyst nematode. The lack of a satisfactory natural amount and the highly biological importance of the compound as well as the unusual skeletal array have prompted us to investigate the chemical synthesis. The unstability of the compound seems to be attributed to the presence of a cross-conjugated moiety included in the C and D rings. Accordingly, we planned to disconnect the synthetic target molecule (1) into two fragments (2) and (3) corresponding to the A ring and C/D ring moieties, respectively, reconnect them, and finally construct the cross-conjugated system in question. We describe herein i) the stereoselective synthesis of the partial structure 2 in an optically pure form starting with readily available 2,2-dimethylcyclohexane-1,3-dione (4); ii) the substituent effects on intramolecular halocyclization reactions of 4-methylenecyclohexanols in connection with the construction of the A ring moiety of 1; iii) the stereoselective synthesis of the partial structure 3 (R=Ac, R^1=Me), starting with commercially available (R)-(-)-carvone (13), which involves stereoselective introduction of four successive assymmetric carbons; and finally iv) the demonstration of the effectiveness of our disconnection by the model experiment (28→29).
天然有機化合物討論会の論文
1985-09-07