  Singlet Higgs bosons present in extensions of the MSSM can have sizable
Yukawa couplings to the b quark and the tau lepton for large values of
tan(beta) at the 1-loop level. We present an effective Lagrangian which
incorporates these tan(beta)-enhanced Yukawa couplings and which enables us to
study their effect on singlet Higgs-boson phenomenology within the context of
both the mnSSM and the NMSSM. In particular, we find that the loop-induced
coupling can be a significant effect for the singlet pseudoscalar, and may
dominate its decay modes. Further implications of the tan(beta)-enhanced Yukawa
couplings for the phenomenology of the singlet Higgs bosons are briefly
discussed.
