A system and method for measuring user affinity in a social network environment is provided. More specifically, the present invention relates to methods for preparing chiral hemiesters from prochiral or meso cyclic acid anhydrides via desymmetrization, using bifunctional cinchona alkaloid catalysts comprising sulfonamide functional groups. This alloy foil is etched, whereby an etched foil having an etching magnification of about 50 times or more and containing pores having an average pore size of about 0. The receiver further includes an adaptive separator, for adaptively separating the mutually correlated chip estimates, and a correlator, for despreading the output of the adaptive separator to obtain an estimate for data symbols of the desired user signal.