1. Show the polyketide, appropriately folded, from which 2-hydroxy-6-methyl-acetophenone is formed.

2. If CD3COOH were used in the biosynthesis of mellein (Figure 4.3), what would be the maximum number of deuterium atoms one could expect to find in mellein?

3. Deduce the polyketide intermediates for each of the three structures in Figure 4.5.

4. What are the arrangements of acetate and propionate units in the pheromone compounds 2-nonanone, 6-methyl-3-octanone and 4-methyl-4-hepten-3-one.

5. Show what further reactions are required on the initial polyketide to give 4,6-dimethyl-4-octen-3-one, an alarm pheromone of the ant Manica rubida.

6. (,R)-(+)-4-Methyl-l-nonanol is a sex pheromone of the yellow mealworm Tenebrio molitor (Coleoptera). Using [l-14C]propionic acid, at what positions in the molecule would one expect to find 14C labelling?

7. Predict the bio synthetic origin of a component of the sex pheromone of the tea tortrix moth below, by drawing its biosynthetic units in position. Careful, it can start with something larger than acetate or propionate!

tea tortrix moth pheromone tea tortrix moth pheromone

0 0

Post a comment