abstract |
The present invention provides an efficient process of reacting a bis-indolyl acid of the Formula (II): <IMAGE> (II) wherein R1 is a hydrogen or C1-C4 alkyl and R, X, and Y are optional substitutions; to produce a bis-indolyloxallic acid of the Formula (III): <IMAGE> (III) Compounds of the Formula (III) are readily converted to the bis-indolylmaleimides. |