Darstellung von cholsäurelactonen

Synthesis, crystal structure and NMR investigation of a new type of cyclic steroidal dimer based on brassinosteroids

“…1 H NMR (500.13 MHz) and 13 C NMR (125.77 MHz) spectra were recorded on a Bruker AVANCE-500 NMR spectrometer. CDCl 3 was used as a solvent and the residual solvent signals (d 7.26 for 1 H NMR and 77.16 for 13 C NMR) served as internal reference standards.…”

“…Steroidal cyclooligomers are usually associated with 'cyclocholates' [1] which are cyclic polyesters of cholic acids with two to six steroid units in the ring [2]. Such compounds are of a great interest for supramolecular chemistry offering a wide perspective for many possible applications [3].…”

Electrospray mass spectrometry and supramolecular complexes: quantifying the metal ion binding properties of cholic acid derivatives

“…The bile acid methyl esters 1È3 were available commercially, internal lactone 4 was synthesised as described by Schulze et al 22 and the cholic acid derivatives 5 to 7 and their macrocyclic counterparts were available as described previously.18 All of the experiments described were carried out using a VG BioQ ES mass spectrometer with a 1 : 1 (v : v) waterÈ acetonitrile solvent system entering the chamber at a rate of 4 lL min~1. The source temperature was 70 ¡C and the cone voltage was set at 85 V. Sample solutions were in the concentration range 10È100 lM and made up in 10 : 45 : 45 (v : v : v) chloroformÈacetonitrileÈwater.…”

Dimeric and Oligomeric Steroids

“…Schulze and co-workers reported the conversion of chenodeoxycholic acid into a dilactone 134 with phenylsulfonyl chloride and pyridine (Scheme ). Under the same reaction conditions both cholic and deoxycholic acids gave 24,12-lactone (i.e., monocyclocholate) derivatives .…”

“…Schulze and co-workers reported the conversion of chenodeoxycholic acid into a dilactone 134 with phenylsulfonyl chloride and pyridine (Scheme ). Under the same reaction conditions both cholic and deoxycholic acids gave 24,12-lactone (i.e., monocyclocholate) derivatives . A bislactone 136 from the reaction of dichloroethyl phosphate with 3α-acetoxy-12α-hydroxy-5β-cholic acid ( 135 , Scheme ) was claimed by Miljkovic and co-workers; the X-ray structure determination used as supportive evidence has never been published and the dimer structure in their Scheme is incorrectly drawn …”