摘要:
Provided is a method for preparing letrozole, which includes reacting an activated bis-(4-cyanophenyl)-methane with a triazole to produce letrozole, and, optionally, purifying the letrozole. Also provided are highly pure letrozole, and a method of purifying letrozole, which method includes precipitating letrozole, e.g., by selective precipitation from a reaction mixture and/or by subjecting the letrozole to one or more crystallizations.
摘要:
A novel process for preparing (2β,3α,5α,16β,17β)-17-acetoxy-3-hydroxy-2-(4-morpholinyl)-16-(1-pyrrolidinyl)androstane, a known intermediate in the synthesis of the skeletal muscle relaxant rocuronium bromide, is disclosed.
摘要:
The present invention provides novel processes for purifying anastrozole, devoid of using liquid chromatography. The purification processes are via the isolated anastrozole salt forms, either by crystallization or by selective acidic extractions, and optionally in both cases, converting the purified anastrozole salt to anastrozole base. Also provided is an improved process for the synthesis of anastrozole, which is obtained by alkylating the isolated and purified starting material 3,5-bis(2-cyanoprop-2-yl)benzylbromide, the process being devoid of using toxic, hazardous and environmental unfriendly solvents and reagents.
摘要:
A novel process for preparing (2β,3α,5α,16β,17β)-17-acetoxy-3-hydroxy-2-(4-morpholinyl)-16-(1-pyrrolidinyl) androstane, a known intermediate in the synthesis of the skeletal muscle relaxant rocuronium bromide, is disclosed.
摘要:
Provided is a method for preparing letrozole, which includes reacting an activated bis-(4-cyanophenyl)-methane with a triazole to produce letrozole, and, optionally, purifying the letrozole. Also provided are highly pure letrozole, and a method of purifying letrozole, which method includes precipitating letrozole, e.g., by selective precipitation from a reaction mixture and/or by subjecting the letrozole to one or more crystallizations.
摘要:
Processes are provided herein for the preparation of pure rocuronium bromide and for the purification of impure rocuronium bromide obviating the need for column chromatography and that can be easily, conveniently and inexpensively scaled-up.