2.7.7.14	crystallization by the sitting-drop vapour diffusion method using PEG 4000 as precipitant. The crystals diffract X-rays from a synchrotron-radiation source to 1.88 A resolution. The space group is assigned as primitive tetragonal, P4(1)2(1)2 or P4(3)2(1)2, with unit-cell parameters a = b = 66.3, c = 150.8. The crystals contain one ECT molecule in the asymmetric unit, with a solvent content of 43%	671090