Synthesis and Biological Activities of Optical Isomers of 2-(4-Chlorophenyl)-5,6-dihydro-(1)benzothiepino(5,4-c)pyridazin-3(2H)-one 7-Oxide.
作者:Tohru NAKAO、Minoru OBATA、Yuko YAMAGUCHI、Nobuhiro MARUBAYASHI、Kuniki IKEDA、Yasuto MORIMOTO
DOI:10.1248/cpb.40.117
日期:——
Two enantiomers of 2-(4-chlorophenyl)-5, 6-dihydro-(1)benzothiepino[5, 4-c]pyridazin-3(2H)-one 7-oxide ((±)-1 : Y-23684) were synthesized in high yields by asymmetric oxidation of the synthetic precursor (2) using modified Sharpless reagent. Among the oxidants tested, cumene hydroperoxide (CHP) gave the highest optical and chemical yields, while tert-butyl, tert-amyl, and 1, 1, 3, 3-tetramethylbutyl hydroperoxides did not show such high enantio-selectivities. The absolute configuration of (+)-1 enantiomer synthesized form 2, Ti(O-iso-Pr)4, (-)-diethyl tartarate, and CHP was determined to be S by X-ray crystallographic analysis. Both enantiomers, S-(+)-1 and R-(-)-1, and (±)-1 had approximately equivalent in vivo activities to antibicuculline test in mice and anticonflict test in rats, although S-(+)-1 showed about three times higher affinity to benzodiazepine receptor than R-(-)-1 in [3H]diazepam binding assay.
通过使用改良夏普莱斯试剂对合成前体 (2) 进行不对称氧化,高产率地合成了 2-(4-氯苯基)-5, 6-二氢-(1)苯并噻吩并[5, 4-c]哒嗪-3(2H)-酮 7-氧化物 ((±)-1:Y-23684) 的两种对映体。在测试的氧化剂中,过氧化积苯(CHP)的光学产率和化学产率最高,而叔丁基、叔戊基和 1, 1, 3, 3-四甲基丁基过氧化氢则没有显示出如此高的对映选择性。通过 X 射线晶体学分析,合成 2、Ti(O-异-Pr)4、(-)-酒石酸二乙酯和 CHP 的 (+)-1 对映异构体的绝对构型被确定为 S。尽管在[3H]地西泮结合试验中,S-(+)-1 与苯并二氮杂卓受体的亲和力比 R-(-)-1高出约三倍,但两种对映体(S-(+)-1 和 R-(-)-1)和 (±)-1 在小鼠抗杜仲碱试验和大鼠抗冲突试验中的体内活性大致相当。