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

Abstract

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