Departures of note

Montague Phillips produced the first sulphapyridine sample on 2 November 1937. The 10‑gram sample was recorded in the May & Baker laboratory test log as T693 and the entry was initialed by Phillips.

The final synthesis step, removal of an acetyl group, did not work with hydrochloric acid, so Phillips used sodium hydroxide. A few grammes of the sample were delivered to Whitby for animal testing under the designation M&B 693.