For example --O-alkyl means alkoxy and --O -cycloalkylmeans cycloalkoxy.In a preferred embodiment, the above process is used to prepare compounds of the formula 1 wherein R.sup.5 is alkyl or cycloalkyl and R.sup.1, R.sup.2 and A are defined as above.Also preferred is a process according to the present invention, wherein R.sup.4 is unsubstituted phenyl or substituted phenyl and, wherein the substit