Stereoselective Total Synthesis of the Putative Structure of Nitraraine
journal contributionposted on 15.08.2014, 00:00 by Federica Arioli, Maria Pérez, Fabiana Subrizi, Núria Llor, Joan Bosch, Mercedes Amat
After the structure originally proposed for nitraraine was shown to be incorrect by total synthesis, the alternative structure 5 was recently suggested for the alkaloid on biosynthetic grounds and by comparison with the 1H NMR data of tangutorine. The unambiguous synthesis of 5 is reported from tryptophanol and ketodiester 6, via oxazoloquinolone lactam 7. However, the melting point and 1H NMR data of 5 did not match those reported for the natural product.