Viral inhibitors, the synthesis thereof, and intermediates thereto

A solid oral pharmaceutical formulation comprising maribavir having a particle size distribution (PSD) characterized by a median particle size (d(50)) of maribavir between about 50 μm and about 400 μm, wherein the solid oral pharmaceutical formulation comprises 200 mg or 400 mg of maribavir, and wherein the solid oral pharmaceutical formulation comprises maribavir, Compound 4, Compound 5, and Compound 8;

• wherein maribavir, Compound 4, Compound 5, and Compound 8 have the following structures:
• wherein Compound 4 is present in an amount of 0.1% w/w or less relative to maribavir, Compound 5 is present in an amount of 0.1% w/w or less relative to maribavir, and Compound 8 is present in an amount of 0.1% w/w or less relative to maribavir.