5-Hydroxy-5α-cholest-8-en-3β-yl acetate (8) (prepared in 6 steps starting from 7-dehydrocholesteryl acetate (1) was transformed with ruthenium tetroxide to 5-hydroxy-8,9-dioxo-8,9-seco-5α-cholestan-3β-yl acetate (9). Treatment of the latter 8,9-seco-5-hydroxy derivative with lead tetraacetate (LTA) or mercuric oxide/iodine reagent (HgO/I2) resulted, instead of the expected oxidative β-fragmentation of its C(5)-C(10) bond, in the competing non-regio and non-stereoselective acetoxylation of the α-positions next to the 8- and 9-oxo functions (with LTA), and in the ≈ 82% recovery of the starting material (with HgO/I2). The results are discussed in terms of the strong hydrogen bonding which exists between the 5α-hydroxyl and the 8-oxo group.
Keywords:
Lactones / Acetates / secosteroidal macrocycles
Source:
Journal of the Serbian Chemical Society, 1997, 62, 9, 719-726
TY - JOUR
AU - Mihailović, Mihailo Lj.
AU - Dabović, Milan
AU - Pavlović, Vladimir D.
AU - Krstić, Natalija
AU - Lorenc, Ljubinka
PY - 1997
UR - http://cer.ihtm.bg.ac.rs/handle/123456789/2707
AB - 5-Hydroxy-5α-cholest-8-en-3β-yl acetate (8) (prepared in 6 steps starting from 7-dehydrocholesteryl acetate (1) was transformed with ruthenium tetroxide to 5-hydroxy-8,9-dioxo-8,9-seco-5α-cholestan-3β-yl acetate (9). Treatment of the latter 8,9-seco-5-hydroxy derivative with lead tetraacetate (LTA) or mercuric oxide/iodine reagent (HgO/I2) resulted, instead of the expected oxidative β-fragmentation of its C(5)-C(10) bond, in the competing non-regio and non-stereoselective acetoxylation of the α-positions next to the 8- and 9-oxo functions (with LTA), and in the ≈ 82% recovery of the starting material (with HgO/I2). The results are discussed in terms of the strong hydrogen bonding which exists between the 5α-hydroxyl and the 8-oxo group.
PB - Serbian Chemical Society
T2 - Journal of the Serbian Chemical Society
T1 - Synthesis and oxidative transformations of 5-hydroxy-5α-cholest-8-en-3β-yl acetate
VL - 62
IS - 9
SP - 719
EP - 726
ER -
@article{
author = "Mihailović, Mihailo Lj. and Dabović, Milan and Pavlović, Vladimir D. and Krstić, Natalija and Lorenc, Ljubinka",
year = "1997",
abstract = "5-Hydroxy-5α-cholest-8-en-3β-yl acetate (8) (prepared in 6 steps starting from 7-dehydrocholesteryl acetate (1) was transformed with ruthenium tetroxide to 5-hydroxy-8,9-dioxo-8,9-seco-5α-cholestan-3β-yl acetate (9). Treatment of the latter 8,9-seco-5-hydroxy derivative with lead tetraacetate (LTA) or mercuric oxide/iodine reagent (HgO/I2) resulted, instead of the expected oxidative β-fragmentation of its C(5)-C(10) bond, in the competing non-regio and non-stereoselective acetoxylation of the α-positions next to the 8- and 9-oxo functions (with LTA), and in the ≈ 82% recovery of the starting material (with HgO/I2). The results are discussed in terms of the strong hydrogen bonding which exists between the 5α-hydroxyl and the 8-oxo group.",
publisher = "Serbian Chemical Society",
journal = "Journal of the Serbian Chemical Society",
title = "Synthesis and oxidative transformations of 5-hydroxy-5α-cholest-8-en-3β-yl acetate",
volume = "62",
number = "9",
pages = "719-726"
}
Mihailović, M. Lj., Dabović, M., Pavlović, V. D., Krstić, N.,& Lorenc, L.. (1997). Synthesis and oxidative transformations of 5-hydroxy-5α-cholest-8-en-3β-yl acetate. in Journal of the Serbian Chemical Society
Serbian Chemical Society., 62(9), 719-726.
Mihailović ML, Dabović M, Pavlović VD, Krstić N, Lorenc L. Synthesis and oxidative transformations of 5-hydroxy-5α-cholest-8-en-3β-yl acetate. in Journal of the Serbian Chemical Society. 1997;62(9):719-726..
Mihailović, Mihailo Lj., Dabović, Milan, Pavlović, Vladimir D., Krstić, Natalija, Lorenc, Ljubinka, "Synthesis and oxidative transformations of 5-hydroxy-5α-cholest-8-en-3β-yl acetate" in Journal of the Serbian Chemical Society, 62, no. 9 (1997):719-726.
