title: Ponasterone A: a new ecdysteroid from the embryos and serum of brachyuran crustaceans.
abstract: The apolar ecdysteroid present in the developing embryo of the blue crab, Callinectes sapidus Rathbun, is tentatively identified as ponasterone A (2 beta, 14 alpha, 20,22-pentahydroxy-5, beta-cholest-7-en-6-one) on the basis of chromatographic, immunological, and mass spectral evidence. The apolar ecdysteroid present in the serum of land crabs, Gecarcinus lateralis, in the late premolt stages of the intermolt cycle is also tentatively identified as ponasterone A on the basis of chromatographic and immunological evidence.
mesh_terms: D000818:Animals; D003386:Brachyura / Q000032:analysis*; D004441:Ecdysterone / Q000031:analogs & derivatives* / Q000302:isolation & purification; D004625:Embryo, Nonmammalian / Q000032:analysis*; D005260:Female; D007118:Immunoassay; D013058:Mass Spectrometry; D011863:Radioimmunoassay; D013056:Spectrophotometry, Ultraviolet
chemical_list: D004441:Ecdysterone; C008999:ponasterone A