Preparation, Pt-195 NMR spectra and biological activity of platinum(IV) complexes with dipeptides

Three dipeptide complexes of the form K[Pt(IV) (dipep)Cl(OH)(2)] and four d ipeptide complexes of the form K[Pt(IV)-(Hdipep)Cl-2(OH)(2)] were newly pre pared. The Pt-195 NMR peaks of the K[Pt(IV) (dipep)Cl(OH)(2)] complexes app eared at about 1200 ppm and these chemical shifts were about 3150 ppm downf ield compared with those of the K [Pt(II) (dipep) Cl] complexes. The chemic al shifts of the K[Pt(TV)(Hdipep)Cl-2(OH)(2)] complexes were at about 900 p pm, i.e., about 3050 ppm downfield compared with those of the K[Pt(II) (Hdi pep) Cl] complexes. The H[Pt(IV) (Hdigly) Cl-2(OH)(2)] and K[Pt(TV) (Hdigly ) Cl-2(OH)Cl] complexes inhibited the growth of C. albicans at a more dilut ed concentration than cisplatin at 1 mu g/ml, but the platinum complexes on ly weakly inhibited the growth of these cells compared with the cisplatin-i nhibited growth of Meth-A and Hep-2 cells at 10 mu g/ml. These results sugg ested that the platinum complexes selectively inhibited the growth of funga l cells. (C) 1999 Elsevier Science Inc. All rights reserved.