ent-4-epi-2), 11-methylhimbacine 3, and 3-epihimbacine 4 in optically pure forms by employing our methodology. All of the synthesized congeners correspond to the compounds modified at the C-3 position of gamma-lactone moiety involved in 1. Among these congeners, 3-demethylhimbacine (3-norhimbacine) 2 was found to exhibit more potent muscarinic M(2) receptor binding affinity than natural 1.
为了揭示我们先前探索的合成途径对天然hebacine 1的收敛性和灵活性,并且,为了阐明1的构效关系的一些新颖方面,我们制备了各种结构类型的新型hebacine同源物3-demethylhimbacine (3-去甲
烟碱)2和4-epi-3-demethylhimbacine((4-epi-3-norhimbacine)4-epi-2及其对映异构体(ent-2和ent-4-epi-2),11-methylhimbacine 3,和采用我们方法学的光学纯形式的3-ephimbacine 4。所有合成的同类物均对应于参与1的γ-内酯部分的C-3位置处修饰的化合物。在这些同类物中,发现3-demethylhimbacine(3-norhimbacine)2显示出更有效的毒蕈碱M(2)受体结合亲和力比天然1。