A new 5-beta-steroid disulphate, with a unique 4-alpha,9-alpha-ether bridge, has been isolated from the ophiuroid Ophiomastix annulosa, together with the minor related compound 2 and the known 3 and 4. The structures of 1 and 2 were deduced mainly from FAB-MS and NMR data. The lowest energy conformation of the desulphated 1a, obtained by Molecular Mechanics calculations in the force field MM2, completely agrees with the H-1-NMR data
Isolation, structure characterization and conformational analysis of a unique 4a,9a-epoxysteroid sulfate fromthe Okinawan ophiuroid Ophiomastix annulosa / D'Auria, MARIA VALERIA; Gomez Paloma, L.; Minale, L.; Riccio, R.; Zampella, Angela; Tanaka, J.; Higa, T.. - In: TETRAHEDRON LETTERS. - ISSN 0040-4039. - STAMPA. - 33:32(1992), pp. 4641-4644. [10.1016/S0040-4039(00)61334-5]
Isolation, structure characterization and conformational analysis of a unique 4a,9a-epoxysteroid sulfate fromthe Okinawan ophiuroid Ophiomastix annulosa
D'AURIA, MARIA VALERIA;ZAMPELLA, ANGELA;
1992
Abstract
A new 5-beta-steroid disulphate, with a unique 4-alpha,9-alpha-ether bridge, has been isolated from the ophiuroid Ophiomastix annulosa, together with the minor related compound 2 and the known 3 and 4. The structures of 1 and 2 were deduced mainly from FAB-MS and NMR data. The lowest energy conformation of the desulphated 1a, obtained by Molecular Mechanics calculations in the force field MM2, completely agrees with the H-1-NMR dataI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
