with s$_{H}$ = − m 2 B − m 2 D 1 − m$_{c}$/m$_{b}$ η 2 b m 2 H ± e iφ τ b , (28) where we have neglected the small contributions from light leptons. Consequently, the contour for R ¯ B → Dτ ¯ ν$_{τ}$ as a function of η$_{b}$/m$_{H}$ ± and φ τ b is displayed in Fig. 5. We have demonstrated that B ( B − → Dτ ¯ ν$_{τ}$ ) is also sensitive to the effects of H $^{±}$. φ τ b [rad] 0.2 0.3$^{0.4}$ 0.5 0.6 η b / m H ± [GeV $^{$_{−}$1}$] 0 0.1 0.2 0.3 0.4 1 2 3 In summary, we find a new scheme for Yukawa couplings in general THDM without imposing symmetry. The scheme not only can avoid FCNC at tree level but also provides a novel couplings of charged Higgs to fermions. With the constraint of b → sγ , we find that the violation of lepton universality can be simplified to be the flavor dependent CP violating phase factor, φ ℓ $_{D$_{j}$}$. Unlike conventional type-II THDM, the new H $^{±}$-mediated effects have the specialties: (a) the influence on Γ( K ± e $_{2}$) / Γ( K ± µ $_{2}$) cannot be eliminated, (b) the decay constant of D$_{s}$ could be enhanced, and (c) enhancement of branching ratio for B + → τ $^{+}$ν could be accomplished. This work is supported by the National Science Council of R.O.C. under Grant Nos. Acknowledgments 11 FIG. 5: Contour for the ratio B ( B − → Dτ ¯ ν$_{τ}$ ) / B ( B − → Dℓ $^{′}$¯ ν$_{ℓ}$ ′ ) as a function of η$_{b}$/m$_{H}$ ± and new phase φ τ $_{b}$.