  In this paper we construct extensions of mixed Hodge structures coming from
the mixed Hodge structure on the graded quotients of the group ring of the
fundamental group of a smooth, projective, pointed curve. These extensions
correspond to the regulators of certain motivic cycles in the Jacobian of the
curve which were constructed by Beilinson and Bloch. This leads to a new
iterated integral expression for the regulator. This is a generalisation of a
theorem of Colombo where she constructed the extension corresponding to
Collino's cycles in the Jacobian of a hyperelliptic curve.
