Isolation and Structure Determination of Aplidinones A–C from the Mediterranean Ascidian Aplidium conicum: A Successful Regiochemistry Assignment by Quantum Mechanical ¹³C NMR Chemical Shift Calculations

Abstract

<jats:title>Abstract</jats:title><jats:p>A chemical investigation of a Mediterranean ascidian, <jats:italic>Aplidium conicum</jats:italic>, has resulted in the isolation of the new metabolites aplidinone A (<jats:bold>1</jats:bold>), B (<jats:bold>2</jats:bold>), and C (<jats:bold>3</jats:bold>). The structures of aplidinones A–C were determined by interpretation of spectroscopic data, whereas the regiochemistry was determined by the comparison of experimental <jats:sup>13</jats:sup>C NMR chemical shifts with those predicted by GIAO shielding calculations. (© Wiley‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2005)