Chapter 25.7, Problem 13P

Interpretation Introduction

Interpretation:

The tail-to-tail linkage synthesis of squalene by the nature has to be explained.

Concept Introduction:

Terpenes are made by joining five –carbon units, usually in a head to tail-fashion.

Monoterpenes are those terpenes with two isoprene units- have 10 carbons, sesquiterpenes have 15 carbons, diterpenes have 20 carbons, triterpenes have 30 carbons and tetraterpenes have 40 carbons.

Isopentenyl pyrophosphate is the five-carbon compound used for the biosynthesis of terpenes.

According to the isoprene rule, the isoprene units are terpenoids joined by head to tail linkage or 1-4-linkage.

Squalene, first isolated from the liver of sharks (genus Squalus), has 30 carbons, 24 in the main chain and 6 in the form of methyl group branches.