Granted Patent
Utility
US 4,697,021 · App. 06/941,890
1,6-dihydro-6-oxo-3-pyridinecarbonitriles, intermediates for cardiotonic agents
Inventors:
George Y. Lesher, Baldev Singh
Patented Case
View Patent ↗
Granted: Sep 29, 1987
Filed: Dec 15, 1986
Inventors
George Y. Lesher
Baldev Singh
Assignee (at issue)
Sterling Drug, Inc.
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.