14214-69-8Relevant academic research and scientific papers
A Convenient Synthesis of Cholesta-1,5,7-trien-3β-ol
Tachibana, Yoji
, p. 3702 - 3704 (1986)
Cholesta-4,6-dien-3β-ol (4) was obtained selectively by the dehydrobromination of 7-bromocholesterol with a base in the presence of a catalytic amount of tetrabutylammonium bromide.The oxidation of 4 with 2,3-dichloro-5,6-dicyano-p-benzoquinone gave cholesta-1,4,6-trien-3-one (7).Treatment of 7 with isopropenyl acetate under acidic conditions afforded (3-acetoxy-1,3,5,7-cholestatetraene which was reduced with calcium borohydride to yield cholesta-1,5,7-triene-3β-ol (2).
Semisynthesis and quantitative structure-activity relationship (QSAR) study of some cholesterol-based hydrazone derivatives as insecticidal agents
Yang, Chun,Shao, Yonghua,Zhi, Xiaoyan,Huan, Qu,Yu, Xiang,Yao, Xiaojun,Xu, Hui
, p. 4806 - 4812 (2013/09/02)
In continuation of our program aimed at the discovery and development of natural-product-based insecticidal agents, four series of novel cholesterol-based hydrazone derivatives were synthesized, and their insecticidal activity was tested against the pre-third-instar larvae of oriental armyworm, Mythimna separata (Walker) in vivo at 1 mg/mL. All the derivatives showed the better insecticidal activity than their precursor cholesterol. Quantitative structure-activity relationship (QSAR) model demonstrated that six descriptors such as RDF085v, Mor06u, Mor11u, Dv, HATS0v and H-046, are likely to influence the insecticidal activity of these compounds. Among them, two important ones are the Mor06u and RDF085v.
Chemoselective reduction of 1,4,6-cholestatrien-3-one and 1,4,6-androstatriene-3,17-dione by various hydride reagents
Kim, Eunjeong,Ma, Eunsook
, p. 360 - 367 (2008/02/04)
The chemoselectivity of rigid cyclic α,β-unsaturated carbonyl group on the reducing agents was influenced by the ring size and steric factor. Cholesterol (cholest-5-en-3β-ol) and dehydroepiandrosterone (DHEA) were oxidized with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone to form 1,4,6-cholestatrien-3-one and 1,4,6-androstatriene-3,17-dione. They were reduced with NaBH4, lithium tri-sec-butylborohydride (l-Selectride), LiAlH4, 9-borabicyclo[3.3.1]nonane (9-BBN), lithium triethylborohydride (Super-hydride), and BH3·(CH3)2S in various conditions, respectively. Reduction of 1,4,6-cholestatrien-3-one and 1,4,6-androstatriene-3,17-dione by NaBH4 (4 equiv.) produced 4,6-cholestadien-3β-ol and 4,6-androstadiene-3β,17β-diol, respectively. Reduction by l-Selectride (12 equiv.) afforded 4,6-cholestadien-3α-ol and 4,6-androstadiene-3α,17β-diol, chemoselectively. Reaction with Super-hydride (12 equiv.) produced 4,6-cholestadien-3-one and 3-oxo-4,6-androstadien-17β-ol. Reduction of 1,4,6-cholestatrien-3-one by 9-BBN (14 equiv.) produced 1,4,6-cholestatrien-3α-ol, but 1,4,6-androstatriene-3,17-dione was not reacted with 9-BBN in the reaction conditions. Reaction of LiAlH4 (6 equiv.) formed 4,6-cholestadien-3β-ol and 3-oxo-1,4,6-androstatrien-17β-ol. Reduction of 1,4,6-cholestatrien-3-one by BH3·(CH3)2S (11 equiv.) gave cholestane as major compound and unlike reactivity of cholesterol, 1,4,6-androstatriene-3,17-dione by 8 equiv. of BH3·(CH3)2S formed 3-oxo-1,4,6-androstatrien-17β-ol. LiAlH4 and BH3·(CH3)2S showed relatively low chemoselectivity.
Epoxidation and reduction of cholesterol, 1,4,6-cholestatrien-3-one and 4,6-cholestadien-3β-ol
Ma, Eunsook,Kim, Haksoon,Kim, Eunjeong
, p. 245 - 250 (2007/10/03)
Many naturally occurring polyhydroxylated sterols and oxysterols exhibit potent biologic activities. This paper describes reagent and position selectivity of epoxidation and reduction of cholesterol derivatives. Cholesterol was reacted with m-chloroperoxybenzoic acid (m-CPBA) to form 5α,6α-epoxycholestan-3β-ol, but in reaction with 30% H 2O2, it did not reacted. 1,4,6-Cholestatrien-3-one was obtained from cholesterol and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone in dioxane. 1,4,6-Cholestatrien-3-one was reacted with 30% H2O 2 and 5% NaOH in methanol to give 1α,2α-epoxy-4,6- cholestadien-3-one, which was stereoselectively reduced with NaBH4 to form 1α,2α-epoxy-4,6-cholestadien-3β-ol and reduced with Li metal in absolute ethanol to give 2-ethoxy-1,4,6-cholestatrien-3-one. And 1,4,6-cholestatrien-3-one was epoxidized with m-CPBA in dichloromethane to afford 6α,7α-epoxy-1,4-cholestadien-3-one, which was reacted with NaBH4 to synthesize 6α-hydroxy-4-cholesten-3-one and reduced Li metal in absolute ethanol to form 2-ethoxy-1,4,6-cholestatrien-3-one, respectively. 1,4,6-Cholestatrien-3-one was reduced with NaBH4 in absolute ethanol to form 4,6-cholestadien-3β-ol, which was reacted with 30% H2O2 to leave original compound, but was reacted with m-CPBA to give 4β,5β-epoxy-6-cholesten-3β-ol as the major product and 4β,5β-epoxy-6α,7α-epoxycholestan-3β-ol as the minor product.
Ene Reactions of Allylically Stannylated Cholestenes: Singlet Oxygenation of 7α-Triphenylstannylcholest-5-en-3β-ol, and of 7α-Triphenylstannyl- and 7α-Tributylstannyl-cholest-5-ene-3-one, and the Rearrangement of 5α-Tributylstannylperoxy-3β-benzyloxycholest-6-ene and of 7α-Trib...
Dang, H.-S.,Davies, Alwyn G.
, p. 1095 - 1101 (2007/10/02)
The reaction of some allylically stannylated steroids with singlet oxygen has been investigated. 7α-Triphenylstannylcholest-4-ene-3β-ol reacts on the β-face with shift of the 4β-hydrogen to give 6β-hydroperoxy-7α-triphenylstannylcholest-4-ene-3β-ol, whereas cholest-5-ene-3β-ol itself reacts on the α-face to give 5α-hydroperoxycholest-6-ene-3β-ol. 7α-Triphenylstannyl- and 7α-tributylstannylcholest-5-ene-3-one give the corresponding 6β-hydroperoxy-7α-stannylcholest-4-ene-3-one (50-55percent), together with the 4,6-dien-3-one which is formed by elimination.In contrast, the parent cholest-5-en-3-one under the same conditions gives some of the 6β-hydroperoxy-4-ene-3-one, but the principal product is the hemiperketal from the 5α-hydroperoxycholest-6-ene-3-one.In neither system was there any evidence for a metalloene reaction, nor for cycloaddition accompanied by a nucleophilic 1,2-shift of the tin. 3β-Benzoyloxy-5α-tributylstannylperoxycholest-6-ene undergoes the Schenck and Smith types of rearrangement by a radical chain mechanism to give successively the corresponding 7α- and 7β-stannylperoxy-5-enes.
