X-ray crystal structure of 3β,22-dihydroxy-23,24-dinorchol-4-ene

Abstract

The crystal structure of 3β,22-dihydroxy-23,24-dinorchol-4-ene, previously synthesised from 3-oxo-23,24-dinorchol-4-ene-22-al, has been determined by X-ray crystallography.

Synthesis of 3α-chlorinated Methyl Lithocholate Derivatives

“…The steroid starting material (methyl lithocholate, 1) was synthesised and identified previously in our lab. 4 Oxalyl chloride (COCl) 2 , phosphorous oxychloride (POCl 3 ), p-TsCl and LAH were purchased from Aldrich. All chemicals and solvents were used throughout without further purification.…”

Synthesis and spectroscopic characterisation lithocholic acid derivatives

“…The solid was filtered off. The filtrate was concentrated, the residue was taken up in ether, washed with H 2 O, dried (MgSO 4 ) and evaporated to dryness to obtain the title compound as a white amorphous solid (2,452 Ph-H), 2.41 (s, 3H, Ph-Me) (lit. 8 1 H NMR: partial assignments); 13 C NMR (Table 1).…”

“…Lithocholic acid (1), is a secondary bile acid, with one functional group at each end of the molecule, which can be modified to useful derivatives. 1 Recently, we reported several lithocholic acid derivatives including monomers and dimers [1][2][3][4] and now we report the synthesis of five lithocholic acid derivatives, 5βcholane-3α,24-diol (2), 3α-hydroxy-5β-cholan-24-yl tosylate (3), 5β-cholan-3α,24-yl ditosylate (4), 3α-tosyloxy-5β-cholan-24-yl chloride (5) and 3-oxo-5β-cholan-24-al (6) together with their full spectroscopic data.…”

“…The hydroxyl groups were converted to their toluene-psulfonates which are excellent leaving groups, that can be displaced by nucleophilic substitution. The tosylates (3)(4)(5) were synthesised from diol 2. 3α-Hydroxy-24-tosylate 3 was synthesised selectively from 2 (Scheme 1).…”

“…In its 13 C NMR spectrum (Table 1), the C-3 and C-24 carbon signals were at further deshielded, at δ 83. 2 The synthesis of five lithocholic acid derivatives, 5β-cholane-3α,24-diol (2), 3α-hydroxy-5β-cholan-24-yl tosylate (3), 5β-cholan-3α,24-yl ditosylate (4), 3α-tosyloxy-5β-cholan-24-yl chloride (5) and 3-oxo-5β-cholan-24-al (6) have been described.…”