The imperfect mirror image relationship of the circular dichroism of (
M) and (P) helical biliverdins bound to a homochiral entity (ICD) has
been studied using the kinetically stable racemates (M + P) 2 and (M P) 3. The phenomena associated with and eventual implications for the
interpretation of ICD spectra of naturally occurring kinetically labi
le biliverdins in terms of chiral recognition are discussed.