Naslov
Chemoenzymatic Synthesis of all four cytoxazone stereoizomers

Autori
Hameršak, Zdenko ; Ljubović, Edina ; Merćep, Mladen ; Mesić, Milan ; Šunjić, Vitomir

Izvornik
Synthesis (0039-7881) 13 (2001); 1989-1992

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Oxazolidinones; Epoxide ring opening; Lipases; Kinetic resolution

Sažetak
Racemic cytoxazone (+/- -5) was synthesized starting from easily available glycidic ester (+/-)-1 by nucleophilic epoxide ring opening, followed by 2-oxazolidinone ring construction and calcium chloride/sodium borohydride reduction of the intermediary ester (+/-)-4. Kinetic resolution of (+/-)-5 performed by acetylation with vinyl acetate catalyzed by Penicillium camemberti lipase (PcamL) afforded, on hydrolysis of acetate (-)-6, cytoxazone (-)-5 in 33% overall yield and 88.2% enantiomeric excess (ee), and its enantiomer (+)-5 (38% yield, 89.3% ee). Base-catalyzed epimerization of intermediary (+/-)-4 to (+/-)-7, and reduction and kinetic resolution with Candida antarctica lipase (CAL) led to epi-cytoxazones (-)-8 and (+)-8.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA