Structure of Prostaglandins Cyclopentane ring with two long side chains trans to each other. Most have 20 carbon atoms. Derived from arachidonic acid. V入COOH 202 √COOH reduction, HOL入 enzyme HO arachidonic acid HH H OOH HH H OH PGF2a => Chapter 25 20 Chapter 25 20 Structure of Prostaglandins • Cyclopentane ring with two long side chains trans to each other. • Most have 20 carbon atoms. • Derived from arachidonic acid. =>