Syntheses of potential spin probes for biomembranes - tempo and proxyl nitroxides of lithocholic acid
摘要:
The synthesis of a steroidal spin label 10 containing a tempo nitroxide group in the side chain of lithocholic acid 1 is reported. This is the first report of a tempo nitroxide in d steroidal side chain. The methodology involved d Wittig condensation between the steroidal phosphonium ylide 7 and tempone 9. The synthesis Of d proxyl nitroxide 16 with the proxyl group in the side chain of 1 is also described. A mild oxidation of 16 to the corresponding 3-keto spin label 17 in high yield is also achieved.
Lithocholic acid (2) was identified as a second endogenous ligand of vitamin D receptor (VDR), though its activity is very weak. In this study, we designed novel lithocholic acidderivatives based on the crystal structure of VDR–ligand-binding domain (LBD) bound to 2. Among the synthesized compounds, 6 bearing a 2-hydroxy-2-methylprop-1-yl group instead of the 3-hydroxy group at the 3α-position of
Lithocholic acid (2) was identified as a second endogenous ligand of vitamin D receptor (VDR), though its activity is very weak. In this study, we designed novel lithocholic acid derivatives based on the crystal structure of VDR–ligand-binding domain (LBD) bound to 2. Among the synthesized compounds, 6 bearing a 2-hydroxy-2-methylprop-1-yl group instead of the 3-hydroxy group at the 3α-position of
On The Protection of 3α-Hydroxy Group of A/B<i>cis</i>Steroids
作者:Sharmila Banerjee Mukhopadhyay、Umesh R. Desai、Girish K. Trivedi
DOI:10.1080/00397919108019755
日期:1991.3
The difficulties encountered in the protection of 3-alpha-hydroxy group of lithocholic acid 1 with three different types of protective groups are described. Only benzyl ether derivative was found to be suitable for synthetic transformations. The methodology for the synthesis of benzyl ethers of A/B cis steroids is reported for the first time.
BANERJEE, SHARMILA;DESAI, UMESH R.;TRIVEDI, GIRISH K., SYNTH. COMMUN., 21,(1991) N, C. 757-770
作者:BANERJEE, SHARMILA、DESAI, UMESH R.、TRIVEDI, GIRISH K.