Process for the preparation of leukotriene anatgonists
AssigneeMerck & Co., Inc.
InventorsMahadevan Bhupathy, James M. McNamara, Daniel R. Sidler, Ralph P. Volante, James Bergan
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Abstract
The present invention relates to a process for the preparation of a compound of formula (I) or a sodium salt thereof ##STR1## wherein HET is 7-chloroquinolin-2-yl or 6,7-difluoroquinolin-2-yl, which comprises: reacting the dilithium dianion of 1-(mercaptomethyl)cyclopropaneacetic acid with a compound of formula (II) ##STR2## wherein HET is as defined above and L is arylsulfonyl or alkylsulfonyl. The invention further provides the dicyclohexylamine salt of a compound of formula (I).
Claims7
A process for the preparation of a compound of formula (I) or a sodium salt thereof ##STR12## wherein HET is 7-chloroquinolin-2-yl or 6,7-difluoroquinolin-2-yl, which comprises:
- generating the dilithium dianion of 1-(mercaptomethyl)cyclo-propaneacetic acid;
- reacting said dianion with a compound of formula (II) ##STR13## wherein HET is as defined above and L is arylsulfonyl or alkylsulfonyl.
A process for the preparation of the crystalline sodium salt of a compound of formula (I) ##STR14## wherein HET is 7-chloroquinolino-2-yl or 6,7-difluoroquinolin-2-yl, which comprises:
- treating the dicyclohexylamine salt of a compound of formula (I) with an acid;
- treating the product thus obtained with a source of sodium ion;
- and
- crystallizing the sodium salt.
Dependencies are inferred from the claim text.