Observation of B0→D*-(5π)+, B+→D*-(4π)++ and B+→D¯*0 (5π)+

We report the first observation of a number of decay modes of the B meson, namely B{sup 0}{yields}D*{sup -}(5{pi}){sup +}, B{sup +}{yields}D*{sup -}(4{pi}){sup ++}, and B{sup +}{yields}D*{sup 0}(5{pi}){sup +}, where (n{pi}) implies the combination of n charged pions. The analysis is based on a 140 fb{sup -1} data sample collected at the {upsilon}(4S) resonance with the Belle detector at KEKB. We measure B[B{sup 0}{yields}D*{sup -}(5{pi}){sup +}]=(4.72{+-}0.59{+-}0.71)x10{sup -3}, B[B{sup +}{yields}D*{sup -}(4{pi}){sup ++}]=(2.56{+-}0.26{+-}0.33)x10{sup -3}, and B[B{sup +}{yields}D*{sup 0}(5{pi}){sup +}]=(5.67{+-}0.91{+-}0.85)x10{sup -3}. We also provide improved measurements of the branching fractions for the decay modes B{sup 0}{yields}D*{sup -}(3{pi}){sup +}, B{sup +}{yields}D*{sup 0}(3{pi}){sup +}, and B{sup 0}{yields}D*{sup 0}(4{pi}){sup 0}.