5976-65-8Relevant articles and documents
A simple, convenient and chemoselective formylation of sterols by Vilsmeier reagent
Srivastava, Vandana,Negi, Arvind Singh,Kumar,Gupta
, p. 632 - 638 (2007/10/03)
Vilsmeier reagent (DMF-POCl3) was used as an efficient formylating agent. Several sterols having sec-hydroxyl group at 3/17-position have been modified into respective formate esters. The method is simple, mild, chemoselective and provides sec-alcoholic protection in good yields.
Methylation of catechol estrogen with diazomethane
Teranishi,Fujii,Yamazaki,Miyabo
, p. 3309 - 3314 (2007/10/02)
Dynamic aspects of methylation of catechol estrogen with diazomethane were investigated by means of thin-layer chromatography. The methylation rate of the hydroxyl group at the C-3 position was almost the same as that of the C-2 hydroxyl group in the reaction of 2-hydroxyestrogen, and 2-3 times that of the C-4 hydroxyl group in the reaction of 4-hydroxyestrogen. In these experiments, the maximum yields of 2-methoxyestrone, 2-hydroxyestrone 3-methyl ether, 4-methoxyesterone and 4-hydroxyesterone 3-methyl ether were 32, 39, 13, and 70%, respectively. In addition, demethylation of catechol estrogen dimethyl ethers with boron tribromide and synthesis of 4-hydroxyestrone monomethyl ethers are described.