  We analyze an extension of the Standard Model with an additional SU(2)
hypercolor gauge group keeping the Higgs boson as a fundamental field.
Vectorlike interactions of new hyperquarks with the intermediate vector bosons
are explicitly constructed. We also consider pseudo-Nambu--Goldstone bosons
caused by the symmetry breaking SU(4)-> Sp(4). A specific global symmetry of
the model with zero hypercharge of the hyperquark doublets ensures the
stability of a neutral pseudoscalar field. Some possible manifestations of the
lightest states at colliders are also examined.
