Isolation and structure elucidation of two phosphorylated sterol sulfates, MT1-MMP inhibitors from a marine sponge Cribrochalina sp.: revision of structures of haplosamates A and B - Fujita, M; Nakao, Y; Matsunaga, S; Seiki, M; Itoh, Y; van Soest, R WM; Heubes, M; Faulkner, D J; Fusetani, N (Tetrahedron, 2001)