title: Diastereoisomers of an 'arsenomethionine'-based structure from Sargassum lacerifolium: the formation of the arsenic-carbon bond in arsenic-containing natural products.
abstract: Separation and 1H NMR spectra of a pair of arsenic-containing diastereoisomers (1a and 1b) isolated from a brown alga has provided support for their structures (proposed on the basis of NMR spectra of the unseparated mixture). The diastereoisomerism and analogies with nitrogen-containing algal lipids indicated that they were derived from an analogue of methionine in which the dimethylarsinoyl- group had replaced amino. Although S-adenosylmethionine is probably the source of methyl and 5'-deoxyribose-5'-yl groups in arsenic-containing natural products, the arsenic-carbon bonds in some compounds might be formed by a process in which arsenic replaces nitrogen in amino-acid synthesis.
authors.affiliation: Department of Chemistry, De Montfort University, The Gateway, Leicester, UK. jedmonds@dmu.ac.uk
authors.forename: J S
authors.initials: JS
authors.lastname: Edmonds
mesh_terms: D000818:Animals; D001152:Arsenicals / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D049872:Bivalvia / Q000378:metabolism; D008055:Lipids / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D000459:Phaeophyceae / Q000737:chemistry / Q000378:metabolism*; D012266:Ribose / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D012436:S-Adenosylmethionine / Q000737:chemistry / Q000378:metabolism; D013237:Stereoisomerism
chemical_list: C413737:2-hydroxy-3-sulfoxypropyl 5-(2-carboxy-3-((2,3-dihydroxypropoxy)propyl)dimethylarseno)-5-deoxyribofuranoside; D001152:Arsenicals; D008055:Lipids; D012266:Ribose; D012436:S-Adenosylmethionine