Isab Anvarhusein A, Wazeer Mohamed I M
Contribution from Department of Chemistry, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.
Spectrochim Acta A Mol Biomol Spectrosc. 2006 Sep;65(1):191-5. doi: 10.1016/j.saa.2005.10.030. Epub 2006 Feb 21.
Complexation of Ag(+) with captopril, 1-[(2S)-3-mercapto-2-methylpropionyl]-L-proline, has been studied by (1)H and (13)C-NMR spectroscopy. The equilibrium constants for the trans to cis isomers of captopril bound to Ag(+) were measured by (1)H NMR spectroscopy. It is observed that the trans isomer of the drug binds more strongly to Ag(+) between pH 5 and 8, as shown by the broadening of the trans isomer's resonances in (13)C NMR spectra on complexation. A monodentate complexation of the trans captopril with Ag(+) via the thiol site is proposed based on the solid-state NMR and IR data. A superior antimicrobial activity is exhibited by the Cap-Ag(I) complex compared to captopril ligand itself against Heterotrotropic Plate Counts (HPC), Pseudomonas aeruginosa and Fecal streptococcus bacteria.
通过¹H和¹³C核磁共振光谱研究了Ag⁺与卡托普利（1-[(2S)-3-巯基-2-甲基丙酰基]-L-脯氨酸）的络合作用。通过¹H核磁共振光谱测量了与Ag⁺结合的卡托普利反式和顺式异构体的平衡常数。观察到，在pH 5至8之间，药物的反式异构体与Ag⁺的结合更强，这通过络合时¹³C核磁共振光谱中反式异构体共振峰变宽得以体现。基于固态核磁共振和红外数据，提出反式卡托普利通过硫醇位点与Ag⁺形成单齿络合物。与卡托普利配体本身相比，Cap-Ag(I)络合物对嗜温性需氧菌总数（HPC）、铜绿假单胞菌和粪肠球菌表现出更强的抗菌活性。
