Abstract: | The synthesis of two isotopomers of L ‐DOPA labelled selectively with tritium is reported. In the intermediate step 3S‐3H]‐, and 3′,5′‐3H2]‐L ‐tyrosine, have been obtained using a combination of chemical and enzymatic methods. The labelled isotopomers of L ‐tyrosine, L ‐Tyr, have been converted into, 3S‐3H]‐, and 5′‐3H]‐L ‐DOPA using the enzyme mushroom tyrosinase (monophenol oxidase, EC 1.14.18.1) from Neurospora crassa. Copyright © 2005 John Wiley & Sons, Ltd. |