19317-90-9

Upstream product

• 809-51-8 7-ketocholesteryl acetate 
• 604-35-3 Cholesteryl acetate 
• 60-33-3 (9E,12E)-Octadeca-9,12-dienoic acid 
• 28290-79-1 trans-linolenic acid 
• 3031-75-2 2-hydroperoxypropane 
• 80-15-9 Cumene hydroperoxide 
• 1371568-03-4 7-benzoyloxycholesterol-3-acetate 
• 57-88-5 cholesterol 
• 77017-36-8 7α-thiophenoxycholesterol acetate 
• 77059-24-6 Acetic acid (3S,7S,8S,9S,10R,13R,14S,17R)-7-benzenesulfinyl-17-((R)-1,5-dimethyl-hexyl)-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-yl ester 
• 19355-87-4 linolenic acid hydroperoxide 
• 7695-64-9 linoleic acid hydroperoxide 
• 14050-40-9 oleic acid hydroperoxide 
• 75-91-2 tert.-butylhydroperoxide 

Downstream Products

• 566-26-7 (3S,7S,8S,9S,10R,13R,14S,17R)-17-((R)-1,5-Dimethyl-hexyl)-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthrene-3,7-diol 
• 434-16-2 7-dehydrocholesterol 
• 1059-86-5 7-Dehydrocholesteryl acetate 
• 567-72-6 cholest-3,5-dien-7-one 
• 35339-47-0 5α,6α-cyclopropa<5,6>cholestan-3β-ol 
• 809-51-8 7-ketocholesteryl acetate 
• 566-93-8 cholesta-4,6-dien-3-one 
• 3862-25-7 Δ⁴-7α-hydrocholesterol 
• 59324-18-4 7α-acetoxy-3β-benzoyloxy-cholestene-(5) 

Relevant academic research and scientific papers

Chemical synthesis of 7α-hydroxycholest-4-en-3-one, a biomarker for irritable bowel syndrome and bile acid malabsorption

7α-Hydroxy-cholest-4-en-3-one is a biomarker for bile acid loss, irritable bowel syndrome, and other diseases associated with defective bile acid biosynthesis. Furthermore, 7α-hydroxy-cholest-4-en-3-one is the physiological substrate for cytochrome P450 8B1 (P450 8B1 or CYP8B1), the oxysterol 12α-hydroxylase enzyme implicated in obesity and cardiovascular health. We report the chemical synthesis of this physiologically important oxysterol beginning with cholesterol. The key feature of this synthesis involves a regioselective C3-allylic oxidation of a 3-desoxy-Δ4-7α-formate steroid precursor to form 7α-formyloxy-cholest-4-en-3-one, which was saponified to yield 7α-hydroxy-cholest-4-en-3-one.

Oxysterols: Synthesis and anti-leishmanial activities

Oxygenated sterols (2-16) were synthesized by skeletal rearrangement of steroidal allylic alcohols. All the derivatives were screened for their anti-leishmanial activities. Compounds 3, 11 and 12 showed potent activities. Compound 12 was found least toxic and induced highest nitric oxide (NO) at 48 h. Least toxicity of compound 12 on splenocytes validated its best anti-amastigote effect and induction of NO.

MnO2/TBHP: A Versatile and User-Friendly Combination of Reagents for the Oxidation of Allylic and Benzylic Methylene Functional Groups

In the presence of activated MnO2, tert-butyl hydroperoxide (TBHP) in CH2Cl2 is able to oxidize the allylic and benzylic methylene groups of different classes of compounds. I describe a one-pot oxidation protocol based on two sequential steps. In the first step, carried out at low temperature, MnO2 catalyses the oxidation of the methylene group. This is followed by a second step where reaction temperature is increased, allowing MnO2 both to catalyse the decomposition of unreacted TBHP and to oxidize allylic alcohols that could possibly be formed. The proposed oxidation procedure is generally applicable, although its efficiency, regioselectivity, and chemoselectivity are strongly dependent on the structure of the substrate. A simple and user-friendly synthetic procedure for the oxidation of allylic and benzylic methylene groups to the corresponding conjugated carbonyl derivatives is described. The proposed oxidation protocol is based on the combined use of MnO2 and tert-butyl hydroperoxide, and is generally applicable.

Selective reduction of α,β-unsaturated steroidal carbonyl compounds by NaBH4in presence of guanidine hydrochloride in dioxane

A selective hydrogenation of α,β-unsaturated steroidal carbonyl compounds with NaBH4in the presence of guanidine hydrochloride in dioxane in good to excellent yields are described.

Synthesis of 7-dehydrocholesterol through hexacarbonyl molybdenum catalyzed elimination reaction

The efficiency of hexacarbonyl molybdenum catalyzed elimination reaction of the allylic acetates has been improved by the presence of O,N- bis(trimethylsilyl) acetamide in the reaction medium. The methodology is particularly well employed for the elimination of 7-acetoxycholesterol-3- acetate(cholestrol-3,7-diacetate) for which the resulting product obtained was exclusively 5,7-homoannular diene(7-dehydrocholesterol-3-acetate). Good yield is achieved (up to 70 %) while decreasing the side products formation and reducing the costs as compared to the previously used procedures. Hexacarbonyl molybdenum elimination reaction is greatly influenced by the reaction temperature, at low as well as at high temperature low yield of the homoannular diene product is separated while at moderate conditions of temperature high products formation is observed.

Efficient chemoenzymatic synthesis, cytotoxic evaluation, and SAR of epoxysterols

A library of diastereomerically pure epoxysterols, prepared by combining chemical and enzymatic methodologies, was evaluated for cytotoxicity toward human cancer and noncancer cell lines. Unsaturated steroids were oxidized by magnesium bis(monoperoxyphthalate) hexahydrate in acetonitrile, and the resulting epimeric epoxides were enzymatically separated using Novozym 435 or lipase AY. Some of the synthesized epoxysterols have potent cytotoxicity and higher activity on cancer cell lines HT29 and LAMA-84.

A new electrochemical system for stereoselective allylic hydroxylation of cholesteryl acetate with dioxygen induced by iron picolinate complexes

The oxygenation reaction of cholesteryl acetate 1 was examined with the FeIII(PA)3/O2/MeCN system using an electrochemical method. The constant potential technique gave mainly the 7-hydroxylated product stereoselectively, along with the 7-oxo product. This oxygenation system is mechanistically unique, requiring iron catalyst, dioxygen, and both cathode and anode.

Sensitized photooxygenation of cholesterol and pseudo-cholesterol derivatives via singlet oxygen

3-Substituted cholesterols and 7-substituted pseudocholesterols undergo a facile photooxygenation sensitized by 9, 10-dicyanoanthracene (DCA) and lumiflavin (LF) to give similar, oppositely-positioned enol derivatives. Both steroids showed the same reaction pattern associated with the endocyclic 5- and 4-olefin units, respectively. The reaction was proposed to proceed via the ene reaction of singlet oxygen and subsequent rearrangement of the initially formed 5α-hydroperoxides.

Iron(III)picolinate-catalyzed oxygenation of cholesteryl acetate with hydrogen peroxide or peracetic acid

The reaction of cholesteryl acetate 1 with a Fe(III)(PA; picolinate)3/H2O2/MeCN system (reagent system A), a simple model system for mono-oxygenases, gave mainly the 7α-hydroxylation product 2a, along with 7-ketonization product 3 and the 5,6-epoxidation product 4. On the other hand, reaction of 1 using a Fe(PA)3/peracetic acid (AcOOH)/MeCN system (reagent system c) or a Fe(III)(ClO4)3 · 9H2O-picolinic acid(PAH)- pyridine(Py)/AcOOH/MeCN system (reagent system F), provided 4 predominantly without formation of 2a. The former reaction may proceed via the dimeric Fe(III)-Fe(V) manifold complex, (PAH)(PA)2Fe(III)-O-O-Fe(V)=O(PA)2 (VII) as a hypothetically active species and a nonradical pathway, and the latter may proceed through monomeric iron complexes, [(PAH)(PA)2Fe(V)=O]+ (IX) and [(PAH)(PA)2Fe(V)(OH)(OOH)I+ (X).

Stereoselective 7α-hydroxylation of 3β-acetoxy-Δ5-steroids by Fe(PA)3/H2O2/MeCN

Stereoselective 7α-hydroxylation reaction of Δ5-steroids by a Fe(PA; picolinate)3/H2O2/MeCN system is presented. The 7α-hydroxylation reactions were achieved in 33-40% yields by addition of 30%-H2O2 to a solution of 3β-acetoxy-Δ5-steroids 1a-1d and a crystalline of Fe(PA)3 in MeCN.