Chapter 18, Problem 83P

Interpretation Introduction

Interpretation: The carbon that will be labeled in orsellinic acid has to be predicted.

Concept introduction: The orsellinic acid is most commonly found in lichens.  It can be synthesized from the condensation of acetyl thioester and malonyl thioester.  The synthesis involved the formation of various intermediates.  The synthesis involves one molecule of acetyl thioester and three molecules of malonyl thioester.  A ring-closure takes place to form a cyclic intermediate which on dehydrogenation forms orsellinic acid.