Granted Patent
Utility
US 4,992,564 · App. 07/401,188
Preparation of 6-substituted 4-chromanones
Inventors:
Jerry R. Patton, Narayanasamy Gurusamy
Patented Case
View Patent ↗
Granted: Feb 12, 1991
Filed: Aug 31, 1989
Inventors
Jerry R. Patton
Narayanasamy Gurusamy
Assignee (at issue)
MALLINCKRODT LLC
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.