| Popis: |
Lavendamycin methyl ester (2), an antitumor antibiotic, was synthesized by a practical and short route in an excellent overallyield of 33% from known starting materials. Pictet-Spengler condensation of 7-acetamido-2-formylquinoline-5,8-dione (4) with the methyl ester of (2RS,3SR)-β-methyltryptophan (5) followed by hydrolysis afforded 2. Aldehyde 4 was prepared by the oxidation of 7-acetamido-2-methylquinoline-5,8-dione (9). Dione 9 was obtained via the Diels-Alder condensation of the novel 1-[(tert-butyldimethylsilyl)oxy]-2-methyl-1-aza-1,3-butadiene (7) with 2-acetamido-6-bromobenzene-1,4-dione (8) |
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