Starfish saponins, Part 2. Steroidal oligoglycosides from the starfish Cosmasterias lurida.
Four new sulfated asterosaponins, designated as cosmasterosides A [1], B [2], C [4], and D [5], have been isolated from the Atlantic starfish Cosmasterias lurida along with large amounts of the pentaglycoside ophidianoside F [3] and the minor component forbeside H [6], previously isolated from Ophidiaster ophidianus and Asterias forbesi, respectively. Cosmasteroside A [1] contains the same oligosaccharide chain as ophidianoside F [3] and a (20S)-5 alpha-cholesta-9(11),24-diene-3 beta,6 alpha,20-triol-3 beta-sulfated aglycone. Cosmasterosides B [2], C [4], and D [5] are based on the known aglycone, thornasterol A, and differ in the number and type of monosaccharide components of the carbohydrate chain. Cosmasteroside B [2] contains a novel oligosaccharide chain that differs from that of ophidianoside F [3] by the replacement of the quinovose unit attached to C-6 of the steroidal aglycone by glucose. The tetraglycosides cosmasterosides C [4] and D [5] are structurally related to ophidianoside F [3] and cosmasteroside B [2], respectively, by the loss of a terminal fucose unit.
Roccatagliata
A J
AJ
Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Ciudad Universitaria, Buenos Aires, Argentina.
Maier
M S
MS
Seldes
A M
AM
Iorizzi
M
M
Minale
L
L
D000818:Animals; D002240:Carbohydrate Sequence; D005260:Female; D006027:Glycosides / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry*; D010053:Ovary / Q000737:chemistry; D012503:Saponins / Q000737:chemistry*; D013215:Starfish / Q000737:chemistry*
D006027:Glycosides; D009844:Oligosaccharides; D012503:Saponins