4-hydroxy-2'-nitrobutyrophenone and tetrahydro-2-(o-nitrophenyl)-2-furanol useful as intermediates in the preparation of a crop-selective herbicide

Granted: Jan 25, 1994 Filed: Dec 29, 1992

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.