MACCLESFIELD, England — Ishan Goshawk, an apprentice with global pharmaceutical company AstraZeneca, donned a lab coat and safety glasses and entered a room filled with robots. His first stop was a machine programmed to fill dozens of tiny vials with a compound he needed for an experiment. Everything seemed in order, so Goshawk went to check on a second robot, a gleaming apparatus that, he noted, cost half a million pounds (about $620,000). When the first robot finished filling the vials, Goshawk would bring them here, to test how efficiently drug compounds can be purified using different solvents.