The computational application of the Cahn–Ingold–Prelog rules 1 and 2

Cahn–Ingold–Prelog (C? I? P) rules 1 and 2 (material differences) have been expressed in the formal logic of a high-level computer language (FORTRAN IV) on a laboratory minicomputer (PDP 11/40) by the program CHIRAL. An oversight in the C? I? P formalism in the treatment of rings was treated on an ad hoc basis; the problem has been expressed simply in terms of elementary graph theory in a way consistent with and similar to chemical notation. An example of the operation of CHIRAL is provided and the internal procedures discussed.