829-20-9Relevant academic research and scientific papers
Peptoid Helix Displaying Flavone and Porphyrin: Synthesis and Intramolecular Energy Transfer
Yang, Woojin,Jo, Junhyuk,Oh, Hyeongyeol,Lee, Hohjai,Chung, Won-Jin,Seo, Jiwon
, p. 1392 - 1400 (2020)
Natural light-harvesting complexes (LHCs) absorb a broad spectrum of sunlight using a collection of photosynthetic pigments whose spatial arrangement is controlled by a protein matrix and exhibit efficient energy transfer. We constructed a novel light-harvesting protein mimic, which absorbs light in the UV to visible region (280-700 nm) by displaying flavone and porphyrin on a peptoid helix. First, an efficient synthesis of 4′-derivatized 7-methoxyflavone (7-MF, 3 and 4) was developed. The flavone-porphyrin-peptoid conjugate (FPPC) was then prepared via Miyaura borylation on a resin-bound peptoid followed by Suzuki coupling between the peptoid and pigment. Circular dichroism spectroscopy indicated that the FPPC underwent helix-to-loop conversion of the peptoid scaffold upon changing the solvent conditions. A distinct intramolecular energy transfer was observed from 7-MF to porphyrin with greater efficiency in the helix than that in the loop conformation of the peptoid, whereas no clear evidence of energy transfer was obtained for unstructured FPPC. We thus demonstrate the value of the helical peptoid, which provided a controlled orientation for 7-MF and porphyrin and modulated the energy transfer efficiency via conformational switching. Our work provides a way to construct a sophisticated LHC mimic with enhanced coverage of the solar spectrum and controllable energy transfer efficiency.
Preparation method of S-configuration phenyl ethyl amine hydrochloride compound
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Paragraph 0088-0090; 0100-0102; 0112-0114, (2021/03/11)
The invention relates to a preparation method of an S-configuration phenyl ethyl amine hydrochloride compound, and relates to the technical field of medicine synthesis and preparation. The preparationmethod comprises the following steps: (1) carrying out Friedel-Crafts reaction on m-dimethoxy benzene and acetyl chloride under the condition of Lewis acid to generate an intermediate A; (2) reactingthe intermediate A with hydroxylamine hydrochloride without separation to generate an intermediate B; (3) reducing the intermediate B under the condition of a reducing agent to obtain a compound C; (4) carrying out organic acid resolution on the compound C to obtain an S-configuration compound D organic salt; and (5) dissociating and salifying the organic salt to obtain a target product compoundE. The preparation method disclosed by the invention has the characteristics of simple purification, low cost, high efficiency, high yield and suitability for industrial mass production.
Dihydropyrazole MurA enzyme inhibitor molecule as well as preparation method and application thereof
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Paragraph 0039-0044, (2021/05/12)
The invention provides a dihydropyrazole MurA enzyme inhibitor molecule as well as a preparation method and application thereof. The structural formula is shown in the specification, R is a direct-connected alkyl group with the chemical formula of CnH2n+1, and n is equal to 1-7. The preparation method comprises the following steps of by taking acetophenone substances with different substituent groups and 4-(4-methyl piperazinyl) benzaldehyde as raw materials, carrying out aldol condensation reaction under an alkaline condition to obtain an intermediate, and synthesizing a target compound with a structural formula by using the intermediate, hydrazine hydrate and an organic acid with an R-COOH structure. The dihydropyrazole MurA enzyme inhibitor molecule provided by the invention has a bacterial inhibition effect, has an MurA enzyme inhibition effect, and also has an effect of interfering synthesis of bacterial cell walls.
STRONGLY LEWIS ACIDIC METAL-ORGANIC FRAMEWORKS FOR CONTINUOUS FLOW CATALYSIS
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Paragraph 0216-0219; 0223; 0239; 0255, (2021/02/26)
Lewis acidic metal-organic framework (MOF) materials comprising triflate-coordinated metal nodes are described. The materials can be used as heterogenous catalysts in a wide range of organic group transformations, including Diels-Alder reactions, epoxide-ring opening reactions, Friedel-Crafts acylation reactions and alkene hydroalkoxylation reactions. The MOFs can also be prepared with metallated organic bridging ligands to provide heterogenous catalysts for tandem reactions and/or prepared as composites with support particles for use in columns of continuous flow reactor systems. Methods of preparing and using the MOF materials and their composites are also described.
Trialkylammonium salt degradation: Implications for methylation and cross-coupling
Assante, Michele,Baillie, Sharon E.,Juba, Vanessa,Leach, Andrew G.,McKinney, David,Reid, Marc,Washington, Jack B.,Yan, Chunhui
, p. 6949 - 6963 (2021/06/02)
Trialkylammonium (most notably N,N,N-trimethylanilinium) salts are known to display dual reactivity through both the aryl group and the N-methyl groups. These salts have thus been widely applied in cross-coupling, aryl etherification, fluorine radiolabelling, phase-transfer catalysis, supramolecular recognition, polymer design, and (more recently) methylation. However, their application as electrophilic methylating reagents remains somewhat underexplored, and an understanding of their arylation versus methylation reactivities is lacking. This study presents a mechanistic degradation analysis of N,N,N-trimethylanilinium salts and highlights the implications for synthetic applications of this important class of salts. Kinetic degradation studies, in both solid and solution phases, have delivered insights into the physical and chemical parameters affecting anilinium salt stability. 1H NMR kinetic analysis of salt degradation has evidenced thermal degradation to methyl iodide and the parent aniline, consistent with a closed-shell SN2-centred degradative pathway, and methyl iodide being the key reactive species in applied methylation procedures. Furthermore, the effect of halide and non-nucleophilic counterions on salt degradation has been investigated, along with deuterium isotope and solvent effects. New mechanistic insights have enabled the investigation of the use of trimethylanilinium salts in O-methylation and in improved cross-coupling strategies. Finally, detailed computational studies have helped highlight limitations in the current state-of-the-art of solvation modelling of reaction in which the bulk medium undergoes experimentally observable changes over the reaction timecourse. This journal is
A sodium trifluoromethanesulfinate-mediated photocatalytic strategy for aerobic oxidation of alcohols
Zhu, Xianjin,Liu, Can,Liu, Yong,Yang, Haijun,Fu, Hua
, p. 12443 - 12446 (2020/10/30)
A sodium trifluoromethanesulfinate-mediated photocatalytic strategy for the aerobic oxidation of alcohols has been developed for the first time, and the photoredox aerobic oxidation of secondary and primary alcohols provided the corresponding ketones and carboxylic acids, respectively, in high to excellent yields.
Synthesis of acyclic and cyclic phosphonates based on substituted 2-hydroxybenzylic alcohols
Brel, V. K.,Mikulenkova, E. A.,Mironov, V. F.,Tatarinov, D. A.,Terekhova, N. V.
, p. 2147 - 2152 (2020/12/09)
A convenient synthesis of benzylic phosphonates and 2,3-dihydrobenzo[d][1,2]oxaphosphole 2-oxides substituted at the aromatic ring, as well as their precursors, 2-hydroxybenzylic alcohols, from the derivatives of salicylic aldehyde, salicylic acid, and 2-hydroxyacetophenone bearing an additional hydroxy or methoxy group at the para position of the aromatic ring was developed. For the first time, the possibility of selective demethylation of the methoxy group positioned ortho to the methylene phosphonate fragment with retention of the methoxy group at the para position was shown.
Kolbe-Schmitt type reaction under ambient conditions mediated by an organic base
Sadamitsu, Yuta,Okumura, Akira,Saito, Kodai,Yamada, Tohru
supporting information, p. 9837 - 9840 (2019/08/20)
The combined use of an organic base for resorcinols realized a Kolbe-Schmitt type reaction under ambient conditions. When resorcinols (3-hydroxyphenol derivatives) were treated with DBU under a carbon dioxide atmosphere, nucleophilic addition to carbon dioxide proceeded to afford the corresponding salicylic acid derivatives in high yields.
A molybdenum based metallomicellar catalyst for controlled and chemoselective oxidation of activated alcohols in aqueous medium
Thiruvengetam, Prabaharan,Chakravarthy, Rajan Deepan,Chand, Dillip Kumar
, p. 123 - 133 (2019/07/19)
A surfactant based oxodiperoxo molybdenum complex, which could activate molecular oxygen, has been employed as a catalyst for controlled oxidation of benzylic alcohols to corresponding carbonyls. The oxidation reactions were carried out under aqueous environment, however, in the absence of any extraneous base or co-catalyst. Sensitive/oxidizable functional groups like cyano, sulfide, hydroxyl, aryl-hydroxyl, alkene (internal/terminal), alkyne (internal/terminal), and acetal were tolerated during the transformations. Such selectivity is attributed to the mild nature of the catalyst. The methodology could also be scaled-up for multi-gram synthesis and the protocol is likely to find practical use since it requires an inexpensive recyclable-catalyst and easily available oxidant (under green conditions). A plausible mechanism is proposed with the help of preliminary computational study.
