Total synthesis of dl-chamaecynone, a termiticidal norsesquiterpene.
作者:TAKASHI HARAYAMA、HIDETSURA CHO、YASUO INUBUSHI
DOI:10.1248/cpb.26.1201
日期:——
The total synthesis of dl-chamaecynone (1), which has termiticidal activity, has been accomplished. The key compound (30a), which has the same four chiral centers as chamaecynone (1), was obtained in a single step by taking advantage of the Diels-Alder reaction of 5-ethynyl-2-methylcyclohex-2-en-1-one (3) with 1-methoxy-3-trimethylsiloxy-1, 3-pentadiene (4). The stereostructure of the major adduct of the Diels-Alder reaction was determined to be the formula (30a) by INDOR experiment. The compound (30a) was converted in four steps into dl-chamaecynone. The preliminary examinations of the Diels-Alder reaction of trans-1-methoxy-3-trimethylsiloxy-1, 3-butadiene (2) with l-carvone and the compound (3) were also carried out, respectively.
已成功完成具有白蚁杀灭活性的dl-chamaecynone(1)的全合成。关键化合物(30a)通过5-乙炔基-2-甲基环己烯-2-酮(3)与1-甲氧基-3-三甲基硅氧基-1,3-戊二烯(4)的Diels-Alder反应,在一步中获得,其具有与chamaecynone(1)相同的四个手性中心。通过INDOR实验确定了Diels-Alder反应主要产物的立体结构为化学式(30a)。化合物(30a)经过四步反应转化为dl-chamaecynone。还分别对trans-1-甲氧基-3-三甲基硅氧基-1,3-丁二烯(2)与l-carvone和化合物(3)的Diels-Alder反应进行了初步研究。