Tsuneo Okonogi

α-Ketothiazole inhibitors of prolyl endopeptidase

Abstract A method is described for the preparation of a series of α-ketohiazole derivatives 1, 2, 3, and 4 which were assayed for proply endopeptidase inhibition. The potent inhibitors 1 and 2 possess a nitrogen atom at a position β to the adjoining ketone moiety.

Peptidyl α-keto thiazole as potent thrombin inhibitors

Abstract We report the synthesis and evaluation of α-keto thiazole derivatives such as D-Phe-Pro-Arg-thiazole 9 as a novel type of thrombin inhibitor. Tripeptidyl α-keto thiazole 9 exhibited the inhibitory activity of thrombin at nanomolar levels and showed a more potent prolongation effect on clotting time than argatroban at a dose of 3 mg/kg intravenously.

Novel 2-methyl-1-oxacephalosporins. II, Synthesis of 3-substituted 2-methyl-1-oxacephem nucleus

The stereoselective syntheses of 3-substituted 2α- and 2β-methyl-1-oxacephems have been achieved through the intramolecular Wittig condensations of 4-(1-methylpropoxy)azetidinones

Novel 2-Methyl-1-oxacephalosporins 1. Synthesis of 2-Methyl-3-nor-1-oxacephem Nucleus

The 2α- and 2β-methyl-1-oxacephems were synthesized stereoselectively starting from (3R,4S)-oxazolinoazetidinone by reaction with chiral alcohols followed by intramolecular carbene insertion of α-diazo-β-keto intermediates