C12H19BrO3, M(r) =291.18, monoclinic, P2(1)/a, a = 12.063(4), b = 19.751(4), c = 12.300(3)Angstrom, beta = 115.86(3)degrees, V = 2637(1)Angstrom(3), Z = 8, D-x = 1.48g.cm(-3) MoK alpha radiation (lambda = 0.71069 Angstrom). The final R indice is 0.11 for 1641 observed reflections.