  We study structure constants of gauge invariant operators in planar N=4
Yang-Mills at one loop with the motivation of determining features of the
string dual of weak coupling Yang-Mills. We derive a simple renormalization
group invariant formula characterizing the corrections to structure constants
of any primary operator in the planar limit. Applying this to the scalar SO(6)
sector we find that the one loop corrections to structure constants of gauge
invariant operators is determined by the one loop anomalous dimension
Hamiltonian in this sector. We then evaluate the one loop corrections to
structure constants for scalars with arbitrary number of derivatives in a given
holomorphic direction. We find that the corrections can be characterized by
suitable derivatives on the four point tree function of a massless scalar with
quartic coupling. We show that individual diagrams violating conformal
invariance can be combined together to restore it using a linear inhomogeneous
partial differential equation satisfied by this function.
