A series of organometallic compounds of general formula [(arene)M(PTA)nXm]Y (arene = η6-C10H14, η-C5Me5); M = Ru(II), Os(II), Rh(III) and Ir(III); X = Cl, mPTA; Y = OTf, PF6) have been screened for their cytotoxicity and ability to inhibit cathepsin B in vitro, in comparison to the antimetastatic compound NAMI-A. The Ru and Os analogues and NAMI-A showed similar enzyme inhibition properties (with IC50 values in the low μM range), whereas the Rh(III) and Ir(III) compounds were inactive. In order to build up a rational for the observed differences, DFT calculations of the metal complexes adducts with N-acetyl-L-cysteine-N′-methylamide, a mimic for the Cys residue in the cathepsin B active site, were performed to provide insights into binding thermodynamics in solution. Initial structure–activity relationships have been defined with the calculated binding energies of the M–S bonds correlating well with the observed inhibition properties of the compounds.
一系列具有一般公式 [(arene)M(
PTA)nXm]Y 的有机
金属化合物(arene = η6-
C10H14, η-C5Me5;M = Ru(II), Os(II), Rh(III) 和 Ir(III);X = Cl, m
PTA;Y = OTf, PF6)已被筛选以评估其细胞毒性和在体外抑制胱
蛋白酶 B 的能力,并与抗转移化合物 N
AMI-A 进行了比较。Ruthenium 和 osmium 的类似物及 N
AMI-A 显示出相似的酶抑制特性(IC50 值在低 μM 范围内),而
铑(III) 和
铱(III) 化合物则表现为无活性。为了探讨观察到的差异,进行了
金属配合物与
N-乙酰-L-半胱氨酸-N′-甲酰胺的 DFT 计算,该物质模拟了胱
蛋白酶 B 活性位点中的半胱
氨酸残基,以提供关于溶液中结合热力学的见解。初步的结构-活性关系已被定义,计算得到的 M–S 键结合能与化合物的观察到的抑制特性良好相关。