Organic compounds -- part of the class 532-570 series – Organic compounds – Carboxylic acid esters
Patent
1990-05-25
1992-09-29
Lee, Mary C.
Organic compounds -- part of the class 532-570 series
Organic compounds
Carboxylic acid esters
560 34, 560 45, 560 47, 560 48, C07C32100, C07C22900
Patent
active
051515440
ABSTRACT:
Disclosed is a process for the synthesis of enantiomerically pure R and S isomers of 2,7-difluoro-4-methoxyspiro[9H-fluorene-9,4-imidazolidene]-2',5'-dione from 2,7-difluoro-4-methoxyfluorenone. Intermediate amino acid esters and urea esters and their preparation are also described.
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Conrow Raymond E.
DuPriest Mark T.
Kuzmich Daniel
Alcon Laboratories Inc.
Brown Gregg C.
Copeland Barry L.
Lee Mary C.
Whittenbaugh Robert C.
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