2,5‐Bis‐(3,4,5‐trimethoxyphenyl)‐2‐oxazoline (5, MDL 100,270) was designed as a potential platelet‐activating factor (PAF) antagonist on the basis of computer modeling comparison studies with known PAF antagonists. An efficient, four‐step synthesis of oxazoline 5 was developed, starting from 3,4,5‐trimethoxybenzaldehyde (6). Oxazoline 5 was found to inhibit the PAF‐induced aggregation of human platelets with an IC50 value of 708 μM.