14 19 10 6 18 20 16 5 OPP OPP 7

Geranylgeranyl pyrophosphate 5 is converted by general acid-base catalysis to 6, and then to the
natural product 7. For clarity only limited atom numbers are shown, but the main chain carbons are
numbered 1 to 16, and the off-chain methyl substituents are numbered 17-20.

A. Use mechanistic arrows on the drawing above to convert 5 to 6, and 6 to 7. Invoke general acids
and general bases as needed, and draw in hydrogens as necessary.
B. On the structure of 7, write in the atom numbers for the carbons marked with an asterisk.