A series of benzophenone oximes appended with sydnone (3a—h) bearing different substituents on aroyl moiety were synthesized to evaluate in vivo and in vitro for their inhibitory activity against purified phospholipase A2 (PLA2) enzymes from snake venom and human inflammatory pleural and ascites fluid. In vivo and in vitro inhibition studies were carried out against PLA2 with respect to the modification of the pharmacophore (substituent) to analyze the specificity for PLA2. The substituent at the aroyl ring was responsible for enhancing the inhibition towards PLA2 enzymes. Most of the newly synthesized compounds inhibit the purified PLA2 enzyme, and the inhibition was more in hydrophobic and aromatic substituents and less when no such substituents were present. The inhibitory effect of the compounds appeared to be due to the direct interaction of compounds with the enzyme. Inhibition is substrate dependent, and the inhibition competes with the substrate for the same binding site of the enzyme. The most active interacting compound 3h from in vitro inhibition of PLA2 activity showed similar potency in the in vivo neutralization of PLA2 induced mouse paw edema and hemolytic activity. Thus, the in vitro inhibition correlated well with the in vivo inhibition and hence the reported derivatives are therapeutically important anti-inflammatory drugs.
合成了一系列在芳酰基部分上附加带有不同取代基的
二苯甲酮肟(3a—h)的
二苯甲酮肟,以评价其对来自蛇毒和人炎症性胸腹
水的纯化
磷脂酶A2(P
LA2)酶的体内和体外抑制活性。通过药效基团(取代基)修饰对 P
LA2 进行体内和体外抑制研究,以分析 P
LA2 的特异性。芳酰环上的取代基负责增强对 P
LA2 酶的抑制。大多数新合成的化合物都会抑制纯化的 P
LA2 酶,并且在疏
水性和芳香族取代基中抑制作用更大,而在不存在此类取代基时抑制作用较小。化合物的抑制作用似乎是由于化合物与酶的直接相互作用。抑制是底物依赖性的,并且抑制与底物竞争酶的相同结合位点。体外抑制 P
LA2 活性 3 小时后最活跃的相互作用化合物在体内中和 P
LA2 诱导的小鼠爪
水肿和溶血活性方面显示出相似的效力。因此,体外抑制与体内抑制良好相关,因此所报道的衍
生物是治疗上重要的抗炎药物。