  In a frustrated J_1-J_2 chain with the nearest-neighbor ferromagnetic
interaction J_1 and the next-nearest-neighbor antiferromagnetic interaction
J_2, novel magnetic states such as a spin-nematic state are theoretically
expected. However, they have been rarely examined in experiments because of the
difficulty in obtaining suitable model compounds. We show here that the
quasi-one-dimensional antiferromagnet NaCuMoO_4(OH), which comprises
edge-sharing CuO_2 chains, is a good candidate J_1-J_2 chain antiferromagnet.
The exchange interactions are estimated as J_1 = - 51 K and J_2 = 36 K by
comparing the magnetic susceptibility, heat capacity, and magnetization data
with the data obtained using calculations by the exact diagonalization method.
High-field magnetization measurements at 1.3 K show a saturation above 26 T
with little evidence of a spin nematic state expected just below the saturation
field, which is probably due to smearing effects caused by thermal fluctuations
and the polycrystalline nature of the sample.
