They showed broad substrate specificities and valuable regioselectivity in the transfer of prenyl units onto indole derivatives. The prenyl side chain could be transferred either at N1, C2, C3, C4, or C7 on the indole ring, depending on the enzyme used, making this methodology a mild and efficient alternative to Friedel–Crafts type prenyl transfer requiring strong Lewis acid activation, and resulting sometimes in undesired side-reactions. In the synthesis of aszonalenin, a ring closure occurred during the prenylation of the benzodiazepinedione intermediate, and 4 stereoisomers could be obtained, depending on the prenyl transferase used and the absolute configuration of the substrate.