5735-97-7Relevant academic research and scientific papers
N-Hydroxyphthalimide-catalyzed radical addition of 1,3-dioxolanes and molecular oxygen to alkenes under ambient conditions: A new route to β-oxycarbonyl compounds
Hirano,Iwahama,Sakaguchi,Ishii
, p. 2457 - 2458 (2000)
A novel catalytic hydroxyacylation of alkenes using 1,3-dioxolanes and molecular oxygen has been developed, and the reaction of 2-methyl-1,3-dioxolane with methyl acrylate under dioxygen atmosphere in the presence of catalytic amounts of NHPI and Co(OAc)2 produced the corresponding adduct in 81% yield.
Zeolites for the Production of Fine Chemicals: Synthesis of the Fructone Fragrancy
Climent,Corma,Velty,Susarte
, p. 345 - 351 (2000)
Fructone (ethyl 3,3-ethylendioxybutyrate), a flavouring material, has been obtained by acetalization of ethyl acetoacetate with ethylene glycol using different microporous and mesoporous aluminosilicates as catalysts. Tridirectional zeolites (Y and Beta) are very effective and selective for carrying out this reaction. It has been found that a higher concentration of acid sites does not guarantee a better catalytic performance and the hydrophobic-hydrophilic properties of the material play a determinant role in this reaction due to the different polarity of the reactants. The coupling between the concentration of active sites and the adequate adsorption properties is achieved for Beta zeolites with a Si/Al ratio between 25 and 50. Optimisation of reaction conditions and the appropriate catalyst allow us to obtain fructone with conversions and selectivities close to 100%.
Chemoenzymatic Synthesis of δ-Keto β-Hydroxy Esters as Useful Intermediates for Preparing Statins
Tartaggia, Stefano,Fogal, Stefano,Motterle, Riccardo,Ferrari, Clark,Pontini, Marta,Aureli, Roberto,de Lucchi, Ottorino
, p. 3162 - 3165 (2016)
Enantiopure (R)-3-hydroxy-5-oxohexanoic acid esters have proven to be useful intermediates in the synthesis of the side chain of statins, in view of the recently described preparation of rosuvastatin and other statins through aldol reactions. Herein, an improved synthesis of these intermediates, by combining chemical and enzymatic reactions, is described. In particular, the selective reduction of a δ-ketal β-keto ester was identified as a key step to obtain derivatives with satisfactory optical purities for use in the synthesis of statins.
HPLC FREE PURIFICATION OF PEPTIDES BY THE USE OF NEW CAPPING AND CAPTURE REAGENTS
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Page/Page column 16; 18, (2020/07/25)
The present disclosure relates to the use of a capping and capture reagent in solid phase peptide synthesis. The present disclosure further relates to a method of solid phase peptide synthesis, wherein a capping and capture reagent according to the present disclosure is used. The present disclosure further relates to a method for purification of a (full-length) synthetic peptide via use of a capping and capture reagent according to the present disclosure. The present disclosure also relates to a kit comprising a capping and capture reagent according to the present disclosure and an amino oxy resin or a hydrazine resin and the use of the kit.
PANTETHEINE DERIVATIVES AND USES THEREOF
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Paragraph 2121, (2020/06/19)
The present disclosure relates to compounds of Formula (I), (II), or (II'): (I), (II), (II'), and pharmaceutically acceptable salts or solvates thereof. The present disclosure also relates to pharmaceutical compositions comprising the compounds and therapeutic and diagnostic uses of the compounds and pharmaceutical compositions.
Total synthesis and anti-inflammatory evaluation of violacin A and its analogues
Liu, Qingyin,Mu, Yu,An, Qi,Xun, Jiali,Ma, Jian,Wu, Wenxi,Xu, Minjuan,Xu, Jun,Han, Li,Huang, Xueshi
, (2019/11/26)
A concise total synthesis of an exceedingly potent anti-inflammatory agent violacin A as well as the preparation of thirty analogues of this lead from commercially available orcinol are described. Highlights of our synthetic efforts involve Friedel-Crafts acylation, the regioselective etherification and esterification of phenolic hydroxyl groups, and Baker-Venkatamaran rearrangement to form basic skeleton of violacin A. The deprotection reaction with Pd-catalytic was involved to avoid the elimination of the hemiacetal hydroxyl at C2. In addition, all synthetic compounds were screened for anti-inflammatory activity against nitric oxide (NO) production using lipopolysaccharide (LPS)-induced Raw264.7 cells. A range of violacin A derivatives 11b, 11d, 11f, 12e, 12g, 13g, 17d-g exhibited stronger anti-inflammatory effect than that of violacin A. Notably, halogeno-benzyloxy substituent at C-7 were favourable for anti-inflammatory activities of violacin A derivatives. Additionally, Western blot results indicated halogeno-benzyloxy derivatives inhibited pro-inflammatory cytokines releases correlated with the suppression of NF-κB signaling pathway.
Design, synthesis and biological evaluation of multifunctional tacrine-curcumin hybrids as new cholinesterase inhibitors with metal ions-chelating and neuroprotective property
Liu, Zhikun,Fang, Lei,Zhang, Huan,Gou, Shaohua,Chen, Li
, p. 2387 - 2398 (2017/04/03)
Total sixteen tacrine-curcumin hybrid compounds were designed and synthesized for the purpose of searching for multifunctional anti-Alzheimer agents. In vitro studies showed that these hybrid compounds showed good cholinesterase inhibitory activity. Particularly, the potency of K3-2 is even beyond tacrine. Some of the compounds exhibited different selectivity on acetylcholinesterase or butyrylcholinesterase due to the structural difference. Thus, the structure and activity relationship is summarized and further discussed based on molecular modeling studies. The ORAC and MTT assays indicated that the hybrid compounds possessed pronounced antioxidant activity and could effectively protect PC12 cells from the H2O2/Aβ42-induced toxicity. Moreover, the hybrid compounds also showed positive metal ions-chelating ability in vitro, suggesting a potential to halt ion-induced Aβ aggregation. All the obtained results demonstrated that the tacrine-curcumin hybrid compounds, in particular compound K3-2, can be considered as potential therapeutic agents for Alzheimer's disease.
Acid-labile δ-ketal-β-hydroxy esters by asymmetric hydrogenation of corresponding δ-ketal-β-keto esters in the presence of CaCO 3
Fan, Weizheng,Li, Wanfang,Ma, Xin,Tao, Xiaoming,Li, Xiaoming,Yao, Ying,Xie, Xiaomin,Zhang, Zhaoguo
supporting information; experimental part, p. 4247 - 4249 (2012/05/05)
A series of acid-labile, optically pure ε-substituted δ-ketal-β-hydroxy esters were obtained by a Ru-SunPhos catalyzed asymmetric hydrogenation of the corresponding ε-substituted δ-ketal-β-keto esters. CaCO3 played a dual role in the hydrogenation reaction - removing the acid generated during the formation of the catalyst and maintaining the activity of the catalyst.
Nonactin biosynthesis: The initial committed step is the condensation of acetate (malonate) and succinate
Nelson, Michael E.,Priestley, Nigel D.
, p. 2894 - 2902 (2007/10/03)
Nonactin is a macrotetrolide antibiotic produced by Streptomyces griseus subsp. griseus ETH A7796 that has shown activity against the P170-glycoprotein efflux pump associated with multiple drug resistant cancer cells. Nonactin is a polyketide, albeit a highly atypical one. The structure is composed of two units of each of the enantiomers of nonactic acid, arranged in a macrocycle, so that the molecule has S4 symmetry and is achiral. The monomer units, (+)- and (-)-nonactic acid, are derived from acetate, succinate, and propionate, although the exact details of the assembly process are quite unclear. We have used feeding experiments with a series of multiple stable isotope labeled precursors to elucidate the details of the first committed step of nonactic acid biosynthesis. We have found that the 13C label from 3-ketoadipate is incorporated specifically into both nonactic acid and its homologue, homononactic acid. The data conclusively show that the first committed step of nonactin biosynthesis is the coupling of a succinate derivative with either acetate or malonate. The differentiation into either nonactate or homononactate occurs after the initial condensation; the homologues are not derived from use of a different "starter unit" by the nonactate polyketide synthase. The first step of nonactin biosynthesis involves achiral intermediates; differentiation between the known enantiocomplementary biosynthesis pathways to form each enantiomer of the precursor monomer units likely occurs after the initial condensation reaction.
BENZAZEPINE DERIVATIVES, PROCESS FOR THE PREPARATION OF THE SAME AND USES THEREOF
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Page 113-114, (2012/10/08)
Compounds of the general formula (I): or salts thereof, which exhibit CCR5 antagonism and exert preventive and therapeutic effects against HIV infections: wherein R1 is a 5- to 6-membered aromatic ring which bears a substituent represented by the general formula: R-Z1-X-Z2- (wherein R1 is hydrogen or optionally substituted hydrocarbyl; X is optionally substituted alkylene; and Z1 and Z2 are each a heteroatom) and may be further substituted, with R being optionally bonded to the aromatic ring to form another ring; Y is optionally substituted imino; and R2 and R3 are each optionally substituted aliphatic hydrocarbyl or an optionally substituted hetero-alicyclic group.
