Granted Patent
Utility
US 4,721,787 · App. 06/780,711
Process for the preparation of benzo-(pyrano and thiopyrano)-pyridines
Inventor:
Alan Hutchison
Patented Case
View Patent ↗
Granted: Jan 26, 1988
Filed: Sep 26, 1985
Inventor
Alan Hutchison
Assignee (at issue)
Ciba-Geigy
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.