Aristeromycin-5‘-carboxaldehyde: A Potent Inhibitor of <i>S</i>-Adenosyl- <scp>l</scp>-homocysteine Hydrolase
作者:Siming Liu、Chong-sheng Yuan、Ronald T. Borchardt
DOI:10.1021/jm950916u
日期:1996.1.1
was the ultimate type-I inhibitor. To elucidate this mechanism of enzyme inhibition, (4'S)- and (4'R)-aristeromycin-5'-carboxaldehydes (1a,b) were synthesized in this study and shown to be potent type-I mechanism-based inhibitors of AdoHcy hydrolase with k2/Ki values of 4.4 x 10(6) and 8.2 x 10(4)M-1min-1, respectively. However, Using 19F NMR and HPLC, it was shown that (4'S)-4,5'-dedehydro-5'-fluoraristeromycin
在较早的研究中,Liu等人。(Bioorg。Med。Chem。Lett。1992,2,1741-1744)表明4',5'-didehydro-5'-氟代阿霉素的E和Z异构体都是非常有效的S-腺苷同型半胱氨酸抑制剂(AdoHcy)水解酶。然而,从机理的角度来看,这些氟乙烯本身是否是引起酶结合NAD +减少的基于I型机理的抑制剂,还是作为终极I型抑制剂的阿霉素5'-甲醛的前药,目前尚不清楚。为了阐明这种酶抑制机制,在本研究中合成了(4'S)-和(4'R)-阿霉素5'-羧醛(1a,b),它们是AdoHcy水解酶的基于I型有效抑制剂k2 / Ki值分别为4.4 x 10(6)和8.2 x 10(4)M-1min-1。然而,使用19 F NMR和HPLC显示,在AdoHcy水解酶存在下,(4'S)-4,5'-脱氢5'-氟代阿霉素不释放氟离子或产生阿霉素5'-甲醛(1a,b)。这些结果表明4',5'-