. . " alkyl, aryl, hydroxyalkyl, oxyalkyl, oxyhydroxyalkyl, carboxyalkyl, carboxyamidealkyl or a couple to a site-directing molecule; R11 is alkyl, alkenyl, oxyalkyl or hydroxyalkyl having up to about 3 carbon atoms and having rotational flexibility around a first-bound carbon atom;where R6 and R9 are other than hydrogen, then R5 and R10 are hydrogen or methyl; andwhere R5 and R10 are other than hydrog" . .