18303-41-8Relevant academic research and scientific papers
Organocatalytic epoxidation and allylic oxidation of alkenes by molecular oxygen
Orfanidou, Maria,Petsi, Marina,Zografos, Alexandros L.
supporting information, p. 9172 - 9178 (2021/11/30)
Pyrrole-proline diketopiperazine (DKP) acts as an efficient mediator for the reduction of dioxygen by Hantzsch ester under mild conditions to allow the aerobic metal-free epoxidation of electron-rich alkenes. Mechanistic crossovers are underlined, explaining the dual role of Hantzsch ester as a reductant/promoter of the DKP catalyst and a simultaneous competitor for the epoxidation of alkenes when HFIP is used as a solvent. Expansion of this protocol to the synthesis of allylic alcohols was achieved by adding a catalytic amount of selenium dioxide as an additive, revealing a superior method to the classical application of t-BuOOH as a selenium dioxide oxidant.
Compound and applications of compound in treatment of cataract
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Paragraph 0073; 0074, (2017/11/18)
The present invention discloses a compound and applications of the compound in treatment of cataract, wherein the structural formula of the compound is represented by a formula I, the compound represented by the formula I and the prodrug or pharmaceutically acceptable salt thereof can be used for preventing, alleviating, or reversing the aggregation of crystallin in cells, more than 90% of the protein components are crystallin (CRY) in the lens cell, and comprise alpha-CRY family, beta-CRY family and gamma-CRY family, and after the crystallin is subjected to mutation, the intracellular protein aggregation can be caused so as to cause the cataract disease. According to the present invention, the effect of the compound is detected by selecting the alpha-CRY family mutants such as alpha-Y118D and alphaB-R120 G, the beta-CRY family mutant such as betaB2-V187E, and the gamma-CRY family mutants such as gammaC-G129C and gammaD-W43R as the research model of the cataract disease; and compared to the existing small molecule (such as C29, Science, 350, 674), the small molecule having the novel structure of the present invention has good activity in the inhibition of the intraocular lens protein mutation induced protein aggregation, can improve the absorption of body on the drug, and does not have toxic-side effect on the normal lens cells.
Regio- and stereoselectivity of diethylaluminum azide opening of trisubstituted epoxides and conversion of the 3° azidohydrin adducts to isoprenoid aziridines
Davis, Chad E.,Bailey, Jessica L.,Lockner, Jonathan W.,Coates, Robert M.
, p. 75 - 82 (2007/10/03)
The regioisomer ratios (3°,2°/2°,3°), and in some cases the stereochemistry, of vicinal azidohydrins formed in reactions of 11 trisubstituted terpene epoxides with Et2AlN3 in toluene are reported. The more highly substituted azide usually predominated (3°,2°/2°,3° ratios ≥ 40:1 to 2.5-1) in accord with a Markovnikov orientation and an SN1-like transition state. Reversed regioisomer ratios were observed with 6,7-epoxygeranyl acetate (1:2.5) and cis-1,2-epoxylimonene (1:3.3 to 1:10). The tertiary azido diols from 2,3-epoxygeraniol, 2,3-epoxyfarnesol, and 2,3-epoxynerol were formed as single isomers with inversion of configuration at C3 (≥ 35-40:1 for the C10 azido diols). The regioselectivity was affected by the presence and proximity of oxy functional groups on the epoxide substrate (OH, OAc, and OSi-tBuMe2), the equivalents of Et2AlN3, and additives (EtOAc or EtOH). The results and trends are rationalized by consideration of the structural and stereoelectronic characteristics of proposed diethylaluminum epoxonium ion intermediates and transition states, together with the nucleophilicity of the azide donor. Six of the 3°,2° azidohydrins were converted to the corresponding aziridines by primary-selective silylations of four azido diols, mesylations, and reductive cyclizations with LiAlH4.
