IP Library Granted Patent US 4,520,203
Granted Patent Utility
US 4,520,203 · App. 06/523,987

Resolution of (.+-.)-1,8-diethyl-1,3,4,9-tetrahydropyrano[3,4-b]indole-1-acetic acid using cinchonine

Inventors: Nedumparambil A. Abraham, Christopher A. Demerson
Patented Case View Patent ↗
Granted: May 28, 1985 Filed: Aug 16, 1983
Inventors
Nedumparambil A. Abraham
Christopher A. Demerson
Assignee (at issue)
Amerimas Home Products, 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.

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Quick Facts
Patent No.
US 4,520,203
App. No.
06/523,987
Filed
1983-08-16
Granted
1985-05-28
Kind
A