New Inducible Nitric Oxide Synthase and Cyclooxygenase-2 Inhibitors, Nalidixic Acid Linked to Isatin Schiff Bases via Certain l-Amino Acid Bridges
作者:Ahmed Naglah、Atallah Ahmed、Zhi-Hong Wen、Mohamed Al-Omar、Abd Amr、Atef Kalmouch
DOI:10.3390/molecules21040498
日期:——
A series of new Schiff bases were synthesized by condensation of isatins with the nalidixic acid-l-amino acid hydrazides. Prior to hydrazide formation, a peptide linkage has been prepared via coupling of nalidixic acid with appropriate l-amino acid methyl esters to yield 3a-c. The chemical structures of the new Schiff bases (5b and 5d-h) were confirmed by means of IR, NMR, mass spectroscopic, and elemental
通过将靛红与萘啶酸-1-氨基酸酰肼缩合,合成了一系列新的席夫碱。在酰肼形成之前,已经通过萘啶酮酸与适当的1-氨基酸甲基酯偶联以制备肽3a-c来制备肽键。新的席夫碱(5b和5d-h)的化学结构已通过IR,NMR,质谱和元素分析得到了证实。通过在脂多糖(LPS)刺激的RAW264.7巨噬细胞模型中测量表达的诱导型一氧化氮合酶(iNOS)和环氧合酶2(COX-2),评估了这些席夫碱的抗炎活性。席夫碱表现出显着的双重抑制作用,对促炎性iNOS和COX-2蛋白的诱导具有可变的效力。然而,与相同浓度(10μM)时对COX-2表达的影响(<56.4%±3.1%抑制)相比,他们将iNOS表达下调至16.5%±7.4%-42.2%±19.6%。相对于COX-2,测试的席夫碱具有更高的iNOS抑制活性,似乎反映了它们的萘啶酸,靛红(4a-c)和1-氨基酸部分对iNOS的综合抑制作用表达。这些合成的萘啶酸-1-