Processes for the preparation of cephalosporin derivatives

• Main Authors: CHUNG IN HWA, LEE KI BONG, LEE IN KYU, SEO DAE WON
• Format: Patent
• Language: English
• Published: 24.11.2009
• Subjects: CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HETEROCYCLIC COMPOUNDS; METALLURGY; ORGANIC CHEMISTRY; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

Provided is a process for preparing a compound of formula 1 or its salt, which comprises reacting a compound represented by the following formula 4 with acetaldehyde in a mixed solvent comprising water, isopropanol, and methylenechloride in a volume ratio of 1:3-6:11-14 in the presence of a first base to stereospecifically prepare a compound represented by the following formula 3'; and reacting the compound of the formula 3' with an anhydrous compound represented by the following formula 2 in the presence of a second base: wherein R1 is a hydrogen or an amino protecting group, R2 is a hydrogen or a carboxyl protecting group, and R3 is a hydrogen or an amino protecting group consisting of phenylacetyl group, wherein when R3 is a phenylacetyl group, R2 is not a hydrogen in formula 3'; and wherein, when at least one of R2 and R3 is a protecting group, all such protecting groups are removed from formula 3', thereby producing a compound represented by formula 6 prior to reacting it with the compound of formula 2.