Two neutral enantiopure arene-ruthenium(II) complexes, [(arene)RuII(κ2(1S,3R)-Ar)Cl2] (1, 2), arene = p-cymene, Ar = o-tolyl or mesityl, derived from the reaction of arene-ruthenium(II) dimers and 1,3-diamino camphor based derivatives, were synthesized. The N1-mesityl-2,2,3-trimethylcyclopentane-1,3-diamine ligand and complex 2 are characterized via X-ray crystallography. Single crystal X-ray structure analysis revealed that 2 crystallizes in monoclinic space group P21 with Z = 4, a = 7.7724(14), b = 14.262(3), c = 14.433(3) Å. Reactivity measurements using UV-Vis of the RuII-arene complexes with guanosine-5′-monophosphate (5′-GMP), 9-methylguanine (9MeG), and L-methionine (L-Met) showed a high affinity towards these nucleophiles. Also, DFT calculations with 2 showed that the reaction with a guanine derivative is thermodynamically favored. Furthermore, the RuII-arene complexes were found to interact with CT-DNA and HT-DNA, and protein BSA. The cytotoxicities of 1 and 2 have been evaluated against human breast cancer cell line (MDA-MB), human cancer colon cell line (HCT-116), human lung carcinoma epithelial cell line (A549), mouse melanoma cell line (B16F10), and mesenchymal stem cells (MSCs) and compared to cisplatin as standard analog. The complexes display relevant activities against all cancer cell lines.