中・大員環化合物の立体化学制御

分子力場計算に基づく立体選択性の予測と天然物合成

抄録

Three general cyclization methods of macrocycles by carbon-carbon bond formation are presented. In the first method (eq.1), recifeiolide (6), phoracantholide J (7) and 13-, 16-membered lactones 8, 9 were synthesized by the intramolecular alkylation of a carbanion generated from a-haloalkyl phenylthioacetate 1. In the second method (eq.2), zearalenone (15) and lasiodiplodin (16) were synthesized by the intramolecular alkylation of a carbanion generated from α-haloalkyl 2-phenylthiomethylbenzoate 10. In the third method (eq.3, 4, 5), macrocyclic ketones, enones and keto lactones, such as exaltone (17), muscone (18), deoxy-trans-resorcylide (19), deoxy-cis-resorcylide (20), zearalenone (15), germacrone (25), humulene (26), bicyclohumulenone (27), acoragermacrone (28) and mukulol (29), were synthesized by the intramolecular alkylation of a carbanion generated from protected cyanohydrins. Moreover stereoselective syntheses of periplanone B (30), 6 (5β) -an-drostene-3, 17-dion (57), costunolide (76) and haageanolide (77), and discussions of the stereoselectivity of the epoxidation of the enone (35), the transannular Diels-Alder reaction of the (E, E, E) -macrocyclic triene (59) and the [2.3] -Wittig rearrangement of the 13-membered diallylic ether 87 and 96 based on ab-initio MM 2 calculations are presented.