Two new oral candidates as anticancer platinum complexes of 1,3-dimethyl pentyl glycine ligand as doping agents against breast cancer.

Abstract 1,3-Dimethylpentylamine (Geranamine) with a similar structure to amphetamine has been used as an athletic performance promoter (doping agent) and also as an indirect sympathomimetic drug to synthesize of 1,3-dimethyl pentyl glycine (13DMPG). Thereafter, two new anticancer platinum complexes as [Pt(DACH)(13DMPG)]NO3 and [Pt(bpy)(13DMPG)]NO3 were synthesized using this ligand and then characterized by spectroscopic methods. ADMET comparative results indicated that they are entirely in the pink area of the Bioavailability Radar, so they can be considered as drug-like and oral medications. Mechanism of tumor inhibition and DNA binding parameters were investigated and the results indicated the higher ability of [Pt(bpy)(13DMPG)]NO3 with the endothermic process for both systems compared with [Pt(DACH)(13DMPG)]NO3. Fluorescence study showed that the quenching mechanism is static for both drugs with large binding constant and high binding (Kb ≈ 8000 M−1 and kq ≈ 5.3 × 1011 M−1 s−1) affinity towards DNA. CD spectra showed the increased intensity of the positive band and the decreased negative band, meaning B-DNA converting to A-DNA form via electrostatic interaction for positively charged complexes. The cytotoxic effect analyzed by MTT assay showed that both compounds have effective antiproliferative on MCF-7 cell line. In addition, the inhibition effect of [Pt(DACH)(13DMPG)]NO3 (IC50 = 17 µM) was shown to be better than [Pt(bpy)(13DMPG)]NO3 (IC50 = 45 µM). According to DFT results, anticancer properties of [Pt(bpy)(13DMPG)]NO3 mainly is more than cisplatin and [Pt(DACH)(13DMPG)]NO3. Docking studies showed that the desolvation energy and hydrogen bond are more effective compared to the other interactions. The torsional free energy, about +1.19 kcal/mol, for both complexes mainly provides groove binding with partially electrostatic and intercalate bindings.