Title compound, 8, has been synthesized from isoquinolinone, 1 (an improved preparation for which is presented) and separated into its antipodes with D-and L-di-p-toluoyltartaric acids. These antipodes and the racemic precursor have been evaluated (and found active) in two in vivo systems for their effects. The most potent of the three,(+)-8, has an EDm of 7.13 pmol/kg for inhibition of spontaneous activity and 7.45 pmol/kg for antinociception ...