A range of macrocycle sizes can be generated, and a variable number of heterocycle rings incorporated into the product.
The final macrocycle may contain 0-6 heterocycles, with the only requirement being that the final residue in the incorporated substrate is cyclic (Pro, ThH, OxH, Thz, Oxz). Unmodified Ser/Thr/Tyr/Trp may be further modified by the addition of a prenyl group.
Shown below are 18 different macrocycles with ring sizes including 6 (blue), 7 (red), 8 (black), 9 (purple) residues, with 2 – 4 heterocycles, plus incorporation of a selenazoline (green) ring. These compounds have been characterised in publications from the company’s founder scientists:
“An Enzymatic Route to Selenazolines”, Jesko Koehnke et al., ChemBioChem, 2013, 14, 564
“An Efficient Method for the In Vitro Production of Azol(in)e-Based Cyclic Peptides”, Wael E. Houssen et al., Angew Chem, 2014, 53, 14171
Other macrocycles have been made incorporating residues with chemical groups suitable for further chemical modification