Chemagis Ltd.

Edna Danon

Joseph Kaspi

Oded Arad

Oded Friedman

Olga Etlin

Lei Zhang

Sonia Krivonos

Mohammed Alnabari

Guy Davidi

Yana Sery

He Xungui

Boris Freger

Liu Xing

Michel Bekhazi

Julia Ditkovitch

Yana Seryi

The present invention provides a process for preparing highly pure Temozolomide base which includes recovery from the purification mother liquors by using an anionic exchange resin. By treating Temozolomide hydrochloride with a mixture of an organic acid, a water miscible organic solvent, and water, Temozolomide free base is obtained in an acidic medium. Due to the high sensitivity of Temozolomide to basic pH values the recovery-including process is especially advantageous because it enables obtaining high yields of highly pure Temozolomide base in acidic conditions. The process for producing Temozolomide base includes hydrolysis of the starting material 8-cyano-3-methyl-[3H]-imidazo[5,1-d]-tetrazin-4-one in acidic medium to obtain highly pure Temozolomide hydrochloride in high yield.

Process for preparing temozolomide

Provided is a process for producing imatinib and salts thereof, e.g., imatinib mesylate. The process includes reacting 4-(4-methyl-piperazin-1-ylmethyl)-benzoic acid with N-(5-amino-2-methylphenyl)-4-(3-pyridyl)-2-pyrimidine-amine in the presence of a carboxylic acid coupling reagent, to produce imatinib, and optionally converting the imatinib into a salt.

Imatinib production process

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.

Letrozole production process

The invention provides a process for the preparation of 6,6-dimethylhept-1-en-4-yn-3-ol comprising of reacting t-butylacetylene with a proton-extracting agent selected from the group consisting of an organometallic compound and metallic lithium to form a t-butylacetylide, reacting the acetylide with acrolein at temperatures between &minus;40&deg; C. to &plus;20&deg; C., quenching the reaction mixture and isolating the product.

Process for the preparation of 6,6-dimethylhept-1-en-4-yn-3-ol

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Meitar, Israel

Edna Danon