Synthesis and evaluation of 3-substituted analogs of 1,2,3,4-tetrahydroisoquinoline as inhibitors of phenylethanolamine N-methyltransferase
作者:Gary L. Grunewald、Daniel J. Sall、James A. Monn
DOI:10.1021/jm00399a024
日期:1988.4
capable of forming a strong enzyme-inhibitor dissociable complex compared to straight-chain derivatives possessing a similar steric component. The good activity of 3-(hydroxymethyl)-THIQ as a PNMT inhibitor cannot be explained solely by steric tolerance for this side chain. We believe that an active-site amino acid residue capable of specific (i.e., hydrogen bond) interactions is located in close proximity
1,2,3,4-四氢异喹啉(THIQ)和THIQ的芳基取代衍生物是催化肾上腺素-苯基乙醇胺N-甲基转移酶形成的酶的有效抑制剂(PNMT,EC 2.1.1.28)。在以前的研究中,我们发现,相对于THIQ本身,用甲基取代THIQ的3位可增强3-甲基-THIQ抑制剂的活性。为了更全面地描绘PNMT活性位点的这一区域,我们合成并评估了其他3位取代的THIQ类似物,其空间和电子特性均不同。8个甲基侧链通过一个亚甲基单元延伸会导致3-乙基-THIQ的效力降低,这表明该活性位点在空间上是紧密的。此外,空间不耐性区域可能主要位于“ 在有效的PNMT抑制剂7,8-dichloro-THIQ(SKF 64139,Ki = 0.24 microM)的3位上掺入羟甲基取代基不会导致17的抑制剂效能得到相同的提高(Ki = 0.38 microM)。该结果表明在该类似物中不允许以芳香族卤素,仲胺和侧链羟基官能团的最佳取向同时结合至PNMT活性位点。