This invention provides processes for synthesizing compounds of formula I:
##STR1##
wherein R is H or alkyl; R.sub.1, R.sub.2 are H, alkyl, alkoxy, halogen,
fluorinated alkyl, --CN, alkyl sulfonamide, alkyl amide, amino,
alkylamino, dialkylamino, fluorinated alkoxy, acyl, or aroyl; R.sub.3 and
R.sub.4 are H, alkyl or cycloalkyl; the dashed line indicates an optional
double bond; as well as intermediates and pharmaceutically acceptable
salts thereof.
