From the above discussion of substituents, one of skill in the art will understand that the term alkyl ismeant to include groups including carbon atoms bound to groups other than hydrogen groups, such as haloalkyl (e.g., --CF.sub.3 and --CH.sub.2CF.sub.3) and acyl (e.g., --C(O)CH.sub.3, --C(O)CF.sub.3, --C(O)CH.sub.2OCH.sub.3, and the like).Similar to the substituents described for the alkyl rad