Novel Au(iii) complexes of aminoquinoline derivatives: crystal structure, DNA binding and cytotoxicity against melanoma and lung tumour cellsElectronic supplementary information (ESI) available: UV spectra of 3, 3 + NaCl, and 1 + calf thymus DNA; fluorescence spectra of the CT-DNA-EB system with increasing amounts of 1 or 3. See http://www.rsc.org/suppdata/dt/b3/b305109a/