New Analogues of Epiboxidine Incorporating the 4,5-Dihydroisoxazole Nucleus: Synthesis, Binding Affinity at Neuronal Nicotinic Acetylcholine Receptors, and Molecular Modeling Investigations
作者:Clelia Dallanoce、Pietro Magrone、Paola Bazza、Giovanni Grazioso、Luca Rizzi、Loredana Riganti、Cecilia Gotti、Francesco Clementi、Karla Frydenvang、Marco De Amici
DOI:10.1002/cbdv.200800077
日期:2009.2
5-dihydro-3-methylisoxazolyl derivatives, structurally related to epiboxidine (=(1R,4S,6S)-6-(3-methylisoxazol-5-yl)-7-azabicyclo[2.2.1]heptane), was prepared via 1,3-dipolar cycloaddition of acetonitrile oxide to different olefins. Target compounds 1a and 1b, 2a and 2b, 3, 4, and 5 were tested for affinity at neuronal nicotinic heteromeric (alpha4beta2) and homomeric (alpha7) acetylcholine receptors. Notably, diastereoisomers
一组新颖的4,5-二氢-3-甲基异恶唑基衍生物,在结构上与表甲吡啶(=(1R,4S,6S)-6-(3-甲基异恶唑-5-基)-7-氮杂双环[2.2.1]庚烷相关通过乙腈氧化物的1,3-偶极环加成反应制得不同的烯烃而制备。测试了目标化合物1a和1b,2a和2b,3、4和5对神经元烟碱异聚体(alpha4beta2)和同聚体(alpha7)乙酰胆碱受体的亲和力。值得注意的是,非对映异构体1a和1b的特征是,与表柔比定(K(i)= 0.6 nM)相比,α4beta2亚型的亲和力大幅下降(K(i)值范围为4.3-126 microM)。因此,用4,5-二氢-3-甲基异恶唑核取代表甲定的3-甲基异恶唑环对于α4β2受体的亲和性是有害的。对于所研究的其余的与表柔丝丁相关的二氢异恶唑衍生物2a和2b,以及3-5,证明了对所研究的两种nAChR亚型的亲和力/选择性的可比性缺乏。将非对映异构体1a和1b以及螺