The selective inhibition of phosphatases by natural toxins: The anhydride domain of tautomycin is not a primary factor in controlling PP1/PP2A selectivity

Analogues of the potent and moderately selective PP1/PP2A inhibitor tautomycin (TM) were prepared with modifications in the C1'-C7' anhydride moiety. While all retain varying degrees of activity within a 3000-fold range of potencies, they also show remarkable constancy in their IC50 ratios, suggesting that the anhydride moiety is not critical in controlling the selectivity of inhibition. (C) 2003 Elsevier Science Ltd. All rights reserved.