The present invention provides a synthetic process for producing bortezomib using a novel intermediate. The present invention also provides a process for purifying bortezomib anhydride, and a new crystalline polymorph of bortezomib anhydride.
A synthetic process for producing bortezomib comprising converting racemic boronic esters, such as the pinacol α-aminoboronic ester, into mixtures of diastereomers [6] by reaction with a suitably protected L-phenylalanine derivative (see Scheme 3), such as N—BOC-L-phenylalanine. The protecting group of the L-phenylalanine moiety is then removed, such as by reacting the diastereomers [6] with an acid, such as hydrochloric acid, to form a mixture of amine salt diastereomers [7] which is then subjected to conditions under which the desired diastereomer (R,S)-[7] is selectively isolated, such as by crystallization, chromatography or stereoselective hydrolysis. The separated desired diastereomer (R,S)-[7] is then converted into bortezomib or bortezomib anhydride.
[EN] CU-AND NI-CATALYZED DECARBOXYLATIVE BORYLATION REACTIONS<br/>[FR] RÉACTIONS DE BORYLATION DÉCARBOXYLATIVE CATALYSÉES PAR CU ET NI
申请人:SCRIPPS RESEARCH INST
公开号:WO2018175173A1
公开(公告)日:2018-09-27
The invention is directed to methods of converting a carboxylic acid group in a compound, via a redox active ester, to a corresponding boronic ester by treatment with bis(pinacolato)diboron-alkyllithium complex in the presence of a ligand, a Ni(ll) salt or a copper salt, and an Mg(ll) salt, in the presence of an alkyllithium or a lithium hydroxide or alkoxide salt. The product pinacolato boronate ester can be cleaved to provide a boronic acid. The invention is also directed to methods of preparing various compounds of medical value comprising boronic acid groups, and to novel boronic-acid containing compounds of medicinal value, including an atorvastatin boronic acid analog, a vancomycin aglycone boronic acid analog, and boronic acid containing elastase inhibitors mCBK319, mCBK320, mCBK323, and RPX-7009.