Proposed biosynthetic pathway to phenylpropenes in
basil. Enzymes are as follows: C4H, cinnamate 4-hydroxylase; C3H,
p-coumarate 3-hydroxylase; CC3H, p-coumaroyl-CoA
3-hydroxylase; CCR, cinnamoyl-CoA reductase; and CAD, cinnamyl alcohol
dehydrogenase. Dotted lines indicate hypothetical reactions;
hypothetical intermediates are boxed. The phenylpropanoid pathway
involving methylations of the CoA esters (as opposed to the free acids)
is shown in brackets.