1—（9H—卟唑—4—氧）—3—取代氨基—2—丙醇类化合物的合成及生物活性（Ⅰ）

目的：寻找有-β－受体阻滞活性,且高效低毒的化合物。方法：以β－受体阻滞剂咔唑洛尔为先导化合物,根据药物设计中的结构拼合原理,对其内醇胺侧链进行结构修饰,设计并合成了10个1－（9H－卟唑－4－氧）－3－取代氨基－2－丙醇类化合物V1－V10。结果和结论：所合成的目的物均未见文献报道,结构经红外光谱、核磁共振氢谱、质谱、元素分析或高分辨质谱确证。初步药理筛选结果显示,10个化合物均能够不同程度地拮抗异丙肾上腺素引起的心支过速,其中化合物V1、V3、V4的活性与先导化合物相似。     

1—（9H—咔唑—4—氧）—3—取代氨基—2—丙醇类化合物的合成及生物活性（Ⅱ）

目的 寻找有β-受体阻滞活性，且高效低毒的化合物。方法 以β-受体阻滞剂咔唑洛尔为先导化合物，根据药物设计中的结构拼合原理，对其丙醇胺侧链进行结构修饰。设计并合成了3个1-（9H-咔唑-4-氧）-3-取代氨基-2-丙醇类化合物V11-V13及其6个相应的酯化物VI1-VI6。结果和讨论 所合成的目的物均未见文献报道，结构经红外光谱，核磁共振氢谱，质谱，元素分析或高分辨质谱确证，初步药理筛选结果显示，9个化合物均能够不同程度地拮抗异丙肾上腺素引起的心动过速，其中化合物V12，Ⅵ3,Ⅵ4的活性与先导化合物相当。     

Competitive and non-competitive interactions between specific ligands and beta-adrenoceptors in living cardiac cells

Summary We have used primary cultures of hearts from newborn rats to study -adrenoceptor properties in living myocardial cells. Receptors were labelled with the lipophilic antagonists ³H-(±)-carazolol and ¹²⁵I-(±)-cyanopindolol (CYP) or with the hydrophilic antagonist ³H-(±)-CGP 12177. Under equilibrium conditions all ligands bound to a saturable homogeneous class of specific sites with a maximal binding capacity of 100 fmol/mg protein (corresponding to 5000 sites/cell). After 90–180 min preincubation of intact cells with ³H-carazolol or ³H-CGP 12177 only 80% of these antagonists could be displaced from specific binding sites by competing ligands. In the simultaneous presence of the antagonist (-) timolol 100% of specifically bound radiolabelled ligand remained displaceable. In competitive displacement experiments the radioligands did not affect the apparent affinity of the displacing nonlabelled antagonists timolol and CGP 12177, but agonist affinity was markedly changed. The apparent K _D values for (-)-isoprenaline were 1560 and 2720 nmol/l in the presence of carazolol and CYP, but only 32 nmol/l in the presence of CGP 12177. This antagonist-dependent difference in agonist K _D values was observed only in intact cells but not in membrane particles prepared from heart homogenates of newborn rats, where high agonist affinity was seen during displacement of all radioligands. The K _A value for isoprenaline-stimulated cAMP accumulation in living cells was 30 nmol/l in 5-day cultures. A direct proportionality existed between agonist receptor occupation and cAMP accumulation in the presence of CGP 12177 as estimated by the K _A/K _D ratio. In the presence of carazolol the K _A/K _D ratio decreased from 1 to 0.02 suggesting that low affinity receptors were not coupled functionally to adenylate cyclase. These results indicate that some lipophilic antagonists which appear to be inert competitive ligands in fragmented membranes, alter receptor binding properties in intact cells. These antagonists seem to promote the transformation of receptor sites into a new inactivated state where competitive interactions between different ligands are inhibited.Part of the results in this study have been presented in preliminary form at the 1981 metting of the Union of Swiss Societies for Experimental Biology (Porzig et al. 1981) and at two symposia held in Basel (Reuter and Porzig 1981 a) and Moscow (Reuter and Porzig 1981 b)