Donald Hou

Intramolecular transaminations of enaminones: a synthesis of fused, polycyclic, N-aryl pyridones

Abstract 2-Arylamino-3-pyridinecarbonyl chlorides acylated the β-carbon atoms of enamines, and the resulting enaminones cyclized to give a series of fused polycyclic N-aryl pyridones. The series included 10-(3-chlorophenyl)-6,8,9,10-tetrahydrobenzo[b][1,8]naphthyridin-5(7H)-one (Sch 40120 ), an antipsoriatic agent.

Novel, stereoselective syntheses of penem antibiotics: efficient, formal syntheses of SCH 34343

Abstract Novel, stereoselective syntheses of (3S, 4R, 5R)-1-(allyloxycarbonyl)methyl-3-[1-hydroxyethyl]-4-β-naphthoxy(thiocarbonyl)thio-2-azetidinone (13) and (3S, 4R, 5R, 3′S, 4′R, 5′R)-4,4′-dithio-bis-1-(allyloxy-carbonyl)methyl-3-[-1-hydroxyethyl]-2-azetidinone (22), key intermediates in the synthesis of the penem antibiotic Sch 34343, were developed starting from readily available 6-aminopenicillanic acid. Advantages of these routes include 1) the highly stereospecific introduction of the hydroxyethyl sidechain with the desired (R)-configuration and 2) the retention of the sulfur of the starting material.