generally not preferred at the para-position. The increase of alkyl branching or addition of a phenyl functional group resulted in slightly increased AC8 inhibition compared to the methyl and ethyl analogs, although the AC8 selectivity remained less than 50% inhibition at the AC1 IC90 concentration for each analog. The best combination of AC1 potency with reduced AC8 inhibition appear to be the ethyl derivatives 20 and 21 with AC1 IC50 values of 0.44 and 0.39 µM and AC8 inhibition of 12% and 19% followed closely by 3-phenyl analog 26 with an AC1 IC50 value of 0.25 µM and AC8 inhibition of 37%. Dose-response curves for analog 20 are shown in Figure and dose-response curves for all analogs are provided in supporting information.