Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5276357 | Tetrahedron Letters | 2007 | 5 Pages |
Quinoline 12 was obtained by a Friedländer reaction from 2-aminobenzaldehyde and methyl acetoacetate. Reduction, silylation then oxidation provided compound 8a. A Pictet-Spengler reaction between the latter and tryptophan methyl ester yielded compound 14, then compound 7 by desilylation. Numerous attempts to prepare a cyclized derivative of this analogue of lavendamycin 7 by conventional ways failed. Fortunately, a good result was obtained via a hemiaminal intermediate and compound 21 was thus obtained in satisfactory yield. A conjugate addition occurred in the course of its reduction which led to compound 22. Biological tests were carried out with compound 7 and the conformationally restricted analogues 21 and 22.
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