  We present a measurement of time-dependent CP-violating asymmetries in decays
of neutral B mesons to the final states D*-+ pi+-, using approximately 82
million B B bar events recorded by the BABAR experiment at the PEP-II e+ e-
storage ring. Events containing these decays are selected with a partial
reconstruction technique, in which only the high-momentum pi+- from the B decay
and the low-momentum pi-+ from the D*-+ decay are used. We measure the
amplitude of the asymmetry to be -0.063 +- 0.024(stat.) +- 0.014(syst.) and
compute bounds on |sin(2beta + gamma)|.
