Introduction

In recent years, a great deal of effort has been devoted to developing transition metal antitumor agent which have better therapeutic properties than the prototype drug Cis-[PtCl₂(NH₃)₂](₁,₂,₃,₄,₅). The bulk of the work to date has involved investigation of the platinum complexes as potential antitumor agent; however some investigation involving palladiums have been done (₆,₇,₈,₉). For the most part palladium (II) complexes have shown little or no antitumor activity compared to platinum (II) complexes. This has been attributed to platinum (II) complexes (₁₀).

On the other hand, it has been found that the platinum complexes which contain good leaving group are responsible for cytotoxic activity of these complexes also, it has been found that the platinum (II) complexes which be charged and water insoluble are lees biological activity and more toxicity (₃,₄).

In an effort to solve the problem including lack of stability of palladium complexes, we have adopted the approach by Gill (₈). This approach involves the use of chelation ligand to stabilize the palladium complexes so that it can reach the cancerous cell intact to be the lack of effective as antitumor agent. On the other hand, to solve the problems of the lack of water- soluble of platinum and palladium complexes and to increase the biological activity, therefore, we chosen the dicarboxylate amino acid (Aspartate and Glutamate) which have intermediate leaving group. Generally, the complexes of amino acids with platinum (II) and Palladium (II) are well known (₁₁,₁₂) and have been of wide interest because of their biological aspect and the variety of their structure properties (₁₃,₁₄,₁₅)

We report the four complexes of 1,4-Bis (amino methyl) cyclo hexane platinum (II) and Palladium (II) containing bidantate dicarboxylate amino acid were compare the in vitro against eight type of pathogenic bacteria, to determine the anti bacterial activity. Structure ability to destroy the bacteria of platinum (II) and palladium (II) complexes.

Materials & methods

All the complexes in this study are listed in the table (1). All complexes were prepared by the same general procedure(₁₆). The method involves reaction of K₂PtCl₄ salt with KI to give K₂PtI₄ which upon reaction with 1,4-Bis - (aminomethyen) cyclohexane (BAMC) at room temperature led to formation beige precipitate to (BAMC) Pt I_2. Because of the high reduction ability of palladium (II) with KI, Na₂PdCl₄ was been reacted with (1) enquire (BAMC) directly to give (BAMC)Pd I₂ .

The yellow precipitate, (BAMC)Pt I₂ and (BAMC)Pd Cl₂ was collected by filtration and washed with water. Reaction of (BAMC)Pt I₂ and (BAMC)Pd Cl₂ with silver sulfate gave of (BAMC)PtSO₄ and (BAMC)Pd SO₄

After silver iodid or silver chloride was filtered off, the reaction of 1,4 (amino methylene)cyclo hexane platinum(II) sulfate or 1,4(amino methylene)cyclo hexane palladium(II) sulfate with barium salts of aspartate or glutamate ligand in aqueous solution at room temperature smoothly afforded the product.

The general synthesis method has been utilized to prepare these complexes are explain in the scheme (1).

Figure 1

Scheme 1 : methods of preparation of complexes [I]-[IV] .

Antibacterial susceptibility

Result

Four complexes of 1,4- bis (amino methylene) cyclohexane platinum (II) and palladium (II) that contain dicarboxylate amino acid have been prepared. Figure (1) illustrates the two amino acid and amino ligands used in this study. Table (1)explains some physical properties of Pt(II) and Pd(II) complexes.

Figure 2

Figure 1: Structure of the dicarboxylate amino acid and amino ligand used in Complexes

Figure 3

Table 1: shown some physical properties and yield to prepared these complexes

The bacterial activity has been measured and summaries in table (2) and the point blew:

1- At (1000 µg/ml) all the synthesis complexes give ability for killed the bacteria except complex [II] against Staph. aureus and Staph. epidermidis also complex [IV] against Staph. aureus. All the complexes not affective low concentration except complex [III] in concentration (250 µg/ml) against Klebsiolla highly anti bacterial activity recorded for Gram positive bacteria, because the cell membrane of this type contain mucopolysaccharides, protein and less amount of phosopholipds and have a less number of pores in the cell envelop. So, the permeability of anti bacterial agent is highly effective against cell membranes.

2-The more active complex is the complex [III] and [IV], and [II] respectively.

3-The complex [III] give (27 mm) against Klebsiolla at concentration (1000 µg/ml).

4-From the results in the table (2), it has been found the palladium (II) has a higher bacterial activity than other complexes.

Figure 4

Table 2:: Growth Inhibitor Zone (mm) , Minimal Inhibitory Concentration (MIC µg/ml)