Methylsteroids. III. Reduction of ketones derived from lanosterol

1957 ◽  
Vol 10 (3) ◽  
pp. 334 ◽  
Author(s):  
CS Barnes ◽  
A Palmer
Keyword(s):  
Hydrogen Transfer ◽  
Carbonyl Groups ◽  
Reduction Of Ketones

The base catalysed hydrogen transfer from solvent alcohol to carbonyl groups is studied with 7,ll-dioxolanostan-3β-yl acetate (I ; R=Ac) and shown to give almost entirely 3β,7β,llβ-trihydroxylanostane (V ; R=R'=H) and the epimeric 3β,7-di-hydroxylanostan-11-ones (VI and VIII ; R=H). Generalizations are made to account for their formation and stereochemistry. The four 3β,7,11-trihydrosylanostanes are prepared.

Hydrogen transfer reduction of ketones catalyzed by Fluka K-10 montmorillonite

1998 ◽  
Vol 136 (2) ◽  
pp. 147-151 ◽  
Author(s):  
David Dolmazon ◽  
Raluca Aldea ◽  
Howard Alper
Keyword(s):  
Hydrogen Transfer ◽  
Reduction Of Ketones

scholarly journals The Flow of the Redox Energy in Quercetin during Its Antioxidant Activity in Water

2020 ◽  
Vol 21 (17) ◽  
pp. 6015
Author(s):  
Zhengwen Li ◽  
Mohamed Moalin ◽  
Ming Zhang ◽  
Lily Vervoort ◽  
Erik Hursel ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Electron Transfer ◽  
Hydroxyl Radicals ◽  
Hydrogen Transfer ◽  
Energy Content ◽  
Quantum Calculations ◽  
Carbonyl Groups ◽  
Oh Groups ◽  
Energy Flows ◽  
Intramolecular Hydrogen

Most studies on the antioxidant activity of flavonoids like Quercetin (Q) do not consider that it comprises a series of sequential reactions. Therefore, the present study examines how the redox energy flows through the molecule during Q’s antioxidant activity, by combining experimental data with quantum calculations. It appears that several main pathways are possible. Pivotal are subsequently: deprotonation of the 7-OH group; intramolecular hydrogen transfer from the 3-OH group to the 4-Oxygen atom; electron transfer leading to two conformers of the Q radical; deprotonation of the OH groups in the B-ring, leading to three different deprotonated Q radicals; and finally electron transfer of each deprotonated Q radical to form the corresponding quercetin quinones. The quinone in which the carbonyl groups are the most separated has the lowest energy content, and is the most abundant quinone. The pathways are also intertwined. The calculations show that Q can pick up redox energy at various sites of the molecule which explains Q’s ability to scavenge all sorts of reactive oxidizing species. In the described pathways, Q picked up, e.g., two hydroxyl radicals, which can be processed and softened by forming quercetin quinone.

Ruthenium(II) Terdentate CNN Complexes: Superlative Catalysts for the Hydrogen-Transfer Reduction of Ketones by Reversible Insertion of a Carbonyl Group into the RuH Bond

2005 ◽  
Vol 117 (38) ◽  
pp. 6370-6375 ◽  
Author(s):  
Walter Baratta ◽  
Giorgio Chelucci ◽  
Serafino Gladiali ◽  
Katia Siega ◽  
Micaela Toniutti ◽  
...  
Keyword(s):  
Carbonyl Group ◽  
Hydrogen Transfer ◽  
Reduction Of Ketones
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