University of Ljubljana, Faculty of Pharmacy, Aškerčeva cesta 7, 1000 Ljubljana, Slovenia.
Xention Limited, Iconix Park, London Road, Pampisford, Cambridge CB22 3EG, UK.
Eur J Med Chem. 2017 Oct 20;139:232-241. doi: 10.1016/j.ejmech.2017.08.015. Epub 2017 Aug 7.
We have prepared three alkaloids from the Agelas sponges, clathrodin, hymenidin and oroidin, and a series of their synthetic analogues, and evaluated their inhibitory effect against six isoforms of the K1 subfamily of voltage-gated potassium channels, K1.1-K1.6, expressed in Chinese Hamster ovary (CHO) cells using automated patch clamp electrophysiology assay. The most potent inhibitor was the (E)-N-(3-(2-amino-1H-imidazol-4-yl)allyl)-4,5-dichloro-1H-pyrrole-2-carboxamide (6g) with IC values between 1.4 and 6.1 μM against K1.3, K1.4, K1.5 and K1.6 channels. All compounds tested displayed selectivity against K1.1 and K1.2 channels. For confirmation of their activity and selectivity, compounds were additionally evaluated in the second independent system against K1.1-K1.6 and K10.1 channels expressed in Xenopus laevis oocytes under voltage clamp conditions where IC values against K1.3-K1.6 channels for the most active analogues (e.g. 6g) were lower than 1 μM. Because of the observed low sub-micromolar IC values and fairly low molecular weights, the prepared compounds represent good starting points for further optimisation towards more potent and selective voltage-gated potassium channel inhibitors.
我们从软海绵 Agelas 属海绵中制备了三种生物碱，即克拉屈滨、海罂粟碱和奥罗辛，并合成了一系列它们的类似物，然后使用自动化膜片钳电生理学检测方法评估了它们对六种电压门控钾通道 K1 亚家族（K1.1-K1.6）亚型在表达中国仓鼠卵巢（CHO）细胞中的抑制作用。最有效的抑制剂是（E）-N-（3-（2-氨基-1H-咪唑-4-基）烯丙基）-4,5-二氯-1H-吡咯-2-甲酰胺（6g），其对 K1.3、K1.4、K1.5 和 K1.6 通道的 IC 值在 1.4 和 6.1 μM 之间。所有测试的化合物均对 K1.1 和 K1.2 通道表现出选择性。为了确认其活性和选择性，还在第二个独立系统中，根据电压钳条件下在非洲爪蟾卵母细胞中表达的 K1.1-K1.6 和 K10.1 通道进行了评估，其中最活跃的类似物（如 6g）对 K1.3-K1.6 通道的 IC 值低于 1 μM。由于观察到的低亚微摩尔 IC 值和相当低的分子量，所制备的化合物代表了进一步优化为更有效和选择性电压门控钾通道抑制剂的良好起点。
