A preferred process is shown in Scheme XV. Nitro vinyl compound (88) is reacted with beta-keto ester 89 in the presence of a base such as sodium ethoxide and the like or a trialkylamine such as triethylamine or diisopropylethylamine and the like or an amidine such as DBU and the like in an inert solvent such as THF, toluene, DMF, acetonitrile, ethyl acetate, isopropyl acetate or methylene chloride