are the terpenes alpha-pinene and alpha-terpinene the same?

Question

I am studying aromatherapy and have been looking at the chemistry of essential oils.  In particular I have come across alpha -pinene and alpha-terpinene.  Are these two compounds the same or different.?  I am very confused.

Answer 1

They are certainly different.  I cannot draw the structure here, but α-pinene is a bicyclic compound while α-terpinene has only one ring.  They both do contain 10 carbon atoms and 16 hydrogen atoms, but they are arranged differently in the 2 compounds.  So, the simple answer to your question is that they are completely different compounds.