(25R)-16β-Acetoxy-3β-bromo-23′,26-epoxy-23′,25-dimethyl-5α-cholest-23,23′-en-6-one dichloromethane monosolvate
نویسندگان
چکیده
The crystal structure of the title compound, C31H45BrO5·CH2Cl2, prepared in six steps from diosgenin, confirmed that the configurations of the stereogenic centers, positions 20S and 25R, remain unchanged during the reaction. The six-membered A, B and C rings have chair conformations. The five-membered ring D has an envelope conformation (with the methyl-substituted C atom fused to ring C as the flap) and the six-membered dihydro-pyran ring E adopts a twist-boat conformation. In the crystal, mol-ecules are linked via C-H⋯O and C-H⋯Cl hydrogen bonds, the latter involving the dichloro-methane solvent mol-ecule, forming a three-dimensional supra-molecular network.
منابع مشابه
Four new furostanol saponins from the rhizomes and roots of Smilax scobinicaulis and their cytotoxicity.
Four new furostanol saponins 1-4, along with two known furostanol saponins 5 and 6 and one known spirostanol saponin 7 were isolated from the rhizomes and roots of Smilax scobinicaulis. The structures of the new saponins were elucidated as 26-O-β-D-glucopyranoside-3β,26-dihydroxy-(25R)-5α-furostan-22-methoxyl-6-one-3-O-α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside (1), 26-O-β-D-glucopyranoside...
متن کاملtrimethylchlorosilane; cholesterol, Cholest-5-en-3b-ol; oxysterols, cholesterol oxidation products; 7-ketocholesterol, cholest-5-en-3b-ol-7-one; cholestanetriol, cholestan-3b,5a,6b-triol; a-epoxycholesterol, cholestan-5a,6a-epoxy-3b-ol; 25-hydroxycholesterol, cholest-5-en-3b,25-diol; 7a-hydroxycholesterol, Cholest-5-en-3b,7a-diol; 7b- hydroxycholesterol, cholest-5-en-3b,7b-diol; b-epoxycholesterol, cholestan-5b,6b-epoxy-3b-ol; 27-hydroxycholesterol, 25R-cholest-5-en-
Abbreviations : HMDS, 1,1,1,3,3,3-hexamethyldisilazane; TMCS, trimethylchlorosilane; cholesterol, Cholest-5-en-3b-ol; oxysterols, cholesterol oxidation products; 7-ketocholesterol, cholest-5-en-3b-ol-7-one; cholestanetriol, cholestan-3b,5a,6b-triol; a-epoxycholesterol, cholestan-5a,6a-epoxy-3b-ol; 25-hydroxycholesterol, cholest-5-en-3b,25-diol; 7a-hydroxycholesterol, Cholest-5-en-3b,7a-diol; 7b...
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