1708-40-3Relevant academic research and scientific papers
Stereoselective synthesis of substituted 5-hydroxy-1,3-dioxanes
Forbes, David C.,Ene, Doina G.,Doyle, Michael P.
, p. 879 - 882 (1998)
A series of 5-hydroxy-1,3-dioxanes has been synthesized using a practical three-step strategy beginning with acetal/ketal formation of tris(hydroxymethyl)aminomethane followed by oxidative cleavage of the amino alcohol. After the ketone was revealed, stereoselective reduction with common hydride reagents, LiAlH4 for the trans isomers and L-Selectride for the cis analogues, gave the target compounds in high yield.
1,3-Bis(t-butyldimethylsiloxy)prop-2-yl 2,5-Dichlorobenzenesulphonate as a Convenient Unit for Fluoroisopropenyl Etherification of Phenols
Shimizu, Makoto,Nakahara, Yuko,Yoshioka, Hirosuke
, p. 867 - 868 (1986)
Phenols are converted into new fluoroisopropenyl ethers via etherification with 1,3-bis(t-butyldimethylsiloxy)prop-2-yl arenesulphonate followed by fluoro-olefination with n-Bu4NF-RSO2F.
Biodegradable poly(ethylene glycol)-poly(?-carprolactone) polymeric micelles with different tailored topological amphiphilies for doxorubicin (DOX) drug delivery
Chen,Zhang,Wu,Peng,Su,Cao,He,Li
, p. 58160 - 58172 (2016)
Three poly(ethylene glycol)-poly(?-carprolactone) (PEG-PCL) copolymers with different topologies but identical molar ratio between PEG to PCL were designed. These copolymers, namely, diblock (L-PEG-PCL), triblock (B-PEG-PCL), and star shaped (S-PEG-PCL) copolymers, were extensively characterized by 1H Nuclear Magnetic Resonance (1H NMR), Fourier Transform Infrared Spectroscopy (FTIR), and Gel Permeation Chromatography (GPC) analyses. The effect of topology on crystallization was investigated by X-Ray Diffraction (XRD), Differential Scanning Calorimetry (DSC). Results showed that the diblock copolymer possessed the highest crystallinity, followed by triblock and star shaped copolymers. Although the topology did not affect the self-assembly behavior of copolymers, the effects on size, size distribution, drug loading content, and drug release rate of the polymeric micelles were observed. The micelles self-assembled from linear diblock copolymer achieved higher cellular uptake and lower half maximal inhibitory concentration (IC50). These findings are favorable to establish the foundation to further design proper structure of amphiphilic copolymers as nanocarrier systems for efficient anticancer therapy.
Synthesis and cytotoxic activity of novel acyclic nucleoside analogues with functionality in click chemistry
G?adysz, Micha?,Ruszkowski, Piotr,Milecki, Jan
, p. 53 - 66 (2018)
We describe synthesis of novel acyclic nucleoside analogues which are building blocks for CuAAC reaction and their activity against two types of human cancer cell lines (HeLa, KB). Three of chosen compounds show promising cytotoxic activity. Synthesis pathway starting from simple and easily accessible substrates employing DMT or TBDPS protective groups is described. Adenosine and thymidine analogues containing alkyne moiety and adenosine analogue containing azido group were synthesized. The obtained units showed ability of forming triazole motif under the CuAAC reaction conditions.
Occurrence of a novel cannabimimetic molecule 2-sciadonoylglycerol (2- eicosa-5',11',14'-trienoylglycerol) in the umbrella pine Sciadopitys verticillata seeds
Nakane, Shinji,Tanaka, Tamotsu,Satouchi, Kiyoshi,Kobayashi, Yuriko,Waku, Keizo,Sugiura, Takayuki
, p. 758 - 761 (2000)
The umbrella pine Sciadopitys verticillata seeds were found to contain a substantial amount (16.7 nmol/g) of sciadonic acid (all-cis-5,11,14- eicosatrienoic acid)-containing 2-monoacylglycerol, i.e., 2- sciadonoylglycerol (2-eicosa-5',11',14'-trienoylglycerol). Because the structure of 2-sciadonoylglycerol closely resembles that of 2- arachidonoylglycerol, the endogenous natural ligand for the cannabinoid receptor, we examined whether or not 2-sciadonoylglycerol exhibits cannabimimetic activity using NG108-15 neuroblastoma x glioma hybrid cells which express the cannabinoid CB1 receptor. We found that 2- sciadonoylglycerol induces rapid transient elevation of intracellular free Ca2+ concentration in NG108-15 cells through a cannabinoid CB1 receptor- dependent mechanism similar to the case of 2-arachidonoylglycerol, yet the activity of 2-sciadonoylglycerol was apparently lower than that of 2- arachidonoylglycerol. The activity of 2-sciadonoylglycerol was detectable from 3-10 nM, reaching a maximum at around 10 μM. To our knowledge, this is the first report showing the occurrence of a cannabimimetic monoacylglycerol in higher plants.
Modified boehmite: A choice of catalyst for the selective conversion of glycerol to five-membered dioxolane
Barik, Manas,Chinnaraja, Eswaran,Dabas, Shilpa,Mishra, Jyotiranjan,Subramanian, Palani S.,Subramanian, Saravanan
, p. 695 - 703 (2022/01/22)
The choice of the active site and support matrix decides the activity of a catalyst. Any modifications on these will have a significant impact on the reactivity and selectivity of the catalyst. Here, we have synthesised WO3-loaded boehmite and applied it for the acetalization of a biomass-derived bulk chemical, glycerol. The well-characterized acid catalyst exhibits a selective acetalization of glycerol with good conversions into a five-membered dioxolane product. The cyclability of the catalyst up to six times along with the retention of the catalytic activity ensures the heterogeneity of the material.
Preparation method of glycerol formal
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Paragraph 0051-0058, (2021/07/21)
The invention discloses a preparation method of benzaldehyde glycerol acetal. The method adopts a solid catalyst composed of phosphomolybdic acid anions and polymeric ionic liquid cations to catalyzethe reaction of benzaldehyde and glycerol, and due to the fine adjustment of acid-base sites, the yield of benzaldehyde glycerol acetal prepared through the method reaches 95%, and meanwhile, the six-membered ring acetal has specific selectivity.
High-efficacy glycerol acetalization with silica gel immobilized Br?nsted acid ionic liquid catalysts - Preparation and comprehending the counter-anion effect on the catalytic activity
Shashni, Shalini,Singh, Vasundhara,Toor, Amrit Pal
, p. 21807 - 21823 (2021/12/09)
Imidazolium sulfonate zwitterions (ZIs) with unconventional counter-anions were used to fabricate a series of mesoporous silica-gel-immobilized Br?nsted acid ionic liquid (SG@BAIL) nanocatalysts. In comparison to traditional heterogeneous catalysts, these immobilised heterogeneous catalysts have the advantage of ionic-liquid acidic sites and the advantage of solid silica gel as a support, increasing their catalytic activities. The catalysts were analysed using a series of physicochemical techniques and their catalytic efficiencies were evaluated during the acetalization of glycerol (G) with benzaldehyde (B). The influence of the counter-anions present in the SG@BAIL catalysts was initially investigated in terms of the percentage conversion vs. the reaction time at a particular temperature. Furthermore, different parametric studies relating to the acetalization reaction were carried out based on the catalyst with the maximum activity. SG-[C3ImC3SO3H][OTf] was observed to have the highest catalytic performance and durability during ecofriendly acetal synthesis, with the highest selectivity for 1,3-dioxane. Parametric studies of the acetalization reaction were carried out, and the catalyst showed noteworthy performance at 90 °C, showing 94% conversion in an equimolar reactant mixture under solvent-free conditions with 0.03 wt% catalyst loading in a short time span of 75 min. In addition, kinetics modelling was performed using reversible second-order kinetics to calculate the forward rate constants at various temperatures. The activation energy of the reaction was determined using the Arrhenius equation, and the overall activation energy was 69.33 kJ mol-1. These investigations have demonstrated the excellent potential of SG@BAIL catalysts for practical application in the glycerol acetalization process.
Structure–Activity Relationships of WOx-Promoted TiO2–ZrO2 Solid Acid Catalyst for Acetalization and Ketalization of Glycerol towards Biofuel Additives
Baithy, Mallesham,Mukherjee, Deboshree,Rangaswamy, Agolu,Reddy, Benjaram M.
, (2021/07/25)
Abstract: WOx-promoted TiO2–ZrO2 solid acid catalyst was prepared and applied in the catalytic acetalization and ketalization of glycerol with carbonyl compounds to produce biofuel additives. The presence of WOx promoter and TiO2 remarkably improved the catalytic activity of ZrO2. Approximately, 100% glycerol conversion was evidenced with non-bulky aliphatic aldehydes and ketones like, propanol and cyclohexanone. The physical characterization of WOx-promoted TiO2–ZrO2, revealed a higher formation of tetragonal crystalline phase of ZrO2, over monoclinic. The total surface acidity and the ratio of Br?nsted to Lewis acidic site concentrations were determined by NH3-TPD and pyridine-chemisorbed FTIR spectroscopy, respectively. A considerably higher concentration of Lewis acidic sites, ~ 213.29?μmol/gm, was evidenced on the WOx-promoted TiO2–ZrO2 catalyst surface. Catalytic activity study revealed a direct correlation between the surface Lewis acidic site concentration and the activity of catalyst. This significant observation indicated the key role of Lewis acidic sites in this catalytic process. The WOx-promoted TiO2–ZrO2 catalyst was also considerably stable and showed good performance in the acetalization/ketalization of glycerol with other substituted carbonyl compounds. Graphic Abstract: The WOx-promoted TiO2–ZrO2 solid acid catalyst exhibits superior catalytic performance for acetalization and ketalization of glycerol with carbonyl compounds to produce biofuel additives. [Figure not available: see fulltext.].
Synthesis of novel seco-acyclo-N-diazolyl-thione nucleosides analogous derived from acetic acid: characterization, complex formation with ions Pb(II), Hg(II) and antibacterial activity
Chehrouri, Manel,Othman, Adil A.
, (2021/08/09)
Three diazoles namely 5-methyl-1,3,4-oxadiazole -2(3H)-thione, 5-methyl-1,3,4-thiadiazol-2(3H)-thione and 4-amino-5-methyl-2H-1,2,4-triazole-3-thiol were synthesized from acetic acid or ethyl acetate. Seco-acyclo-N-nucleoside analogous was synthesized by condensation of 1,3-benzylidine-glyceryl-2-tosylate with the three diazoles. Structural proof was based upon IR, 1H-NMR, 13C-NMR spectroscopy and MS measurements. The tendency to form complex between 1,3,4-oxadiazole and 1,3,4-thiadiazoles and Pb(II) and Hg(II) ions was achieved, and their structures were assigned by observing some changes in physical properties such as, MP, coloration, Rf (TLC), IR and UV spectroscopy. Most compounds were tested in vitro against Gram-positive and Gram-negative bacteria and showed variable activity. Hg2+ complexes of oxadiazole and thiadiazole derivatives exhibited appreciable antibacterial effect at lower MIC, compatible to the reference vancomycin. Similarly, oxadiazole-nucleoside exhibited high effect on Gram-positive bacteria. Graphic abstract: [Figure not available: see fulltext.]
