Abstract
A quantitative structure-activity relationship for benzyl pyridinium ions inhibiting complement has been formulated. The best equation describing the relationship is log 1/C=0.18π-1+0.46π-2+1.01σ+-1+0.72D-1+2.50 where C is the molar concentration causing 50% inhibition of complement, π-1 is the hydrophobic constant for substituents on the pyridine moiety and π-2 for substituents on the benzyl moiety, σ+-1 refers to the electronic effects of substituents on the pyridine ring, and the indicator variable D-1 refers to the SO2F function in the 2-position of the benzene ring. This expression correlates 69 derivatives with a correlation coefficient of 0.939 and a standard deviation of 0.198. The implications of this relationship for the design of inhibitors is discussed.
