Note that these types of questions are often the most difficult on the examination. This is because they are holistic in that they require a good understanding of the reactions and the concepts and the ability to apply those concepts. They can't be memorised, they require understanding and ability to apply. Hence they help discriminate those who truly understand from those who have memorised and will soon forget.

A simple schematic of the solution is presented below. Unlike other years, this is NOT a how to get the answer (time constraints)

Key  steps are :

• nomenclature !
  
• F must be a exocyclic alkene due to ozonolysis product - the other product is C1 and therefore must be methanal
• From F deduce C and then hence A by paying attention to regioselectivity.
  
• From the tricyclic product, recognise the Diels-Alder and push the curly arrows in the retro-Diels-Alder to give B and H
• From B work out G