3958-60-9Relevant articles and documents
A photo-degradable injectable self-healing hydrogel based on star poly(ethylene glycol)-: B -polypeptide as a potential pharmaceuticals delivery carrier
Zhao, Dinglei,Tang, Quan,Zhou, Qiang,Peng, Kang,Yang, Haiyang,Zhang, Xingyuan
, p. 7420 - 7428 (2018)
As one of the most promising biomaterials, injectable self-healing hydrogels have found broad applications in a number of fields such as local drug delivery. However, controlled release of drugs in hydrogels is still difficult to realize up to now. Here, we report a novel photo-degradable injectable self-healing hydrogel based on the hydrophobic interaction of a biocompatible four-arms star polymer, poly(ethylene glycol)-b-poly(γ-o-nitrobenzyl-l-glutamate). The hydrophobic interaction between poly(γ-o-nitrobenzyl-l-glutamate) not only connects poly(ethylene glycol)-b-poly(γ-o-nitrobenzyl-l-glutamate) together with a crosslink but also provides a hydrophobic domain to encapsulate hydrophobic pharmaceuticals such as doxorubicin (DOX). Due to the dynamic character of the hydrophobic interaction, the hydrogel exhibits excellent injectable and self-healing ability. In particular, the photolabile o-nitribenzyl ester group is cleaved under UV irradiation. As a result, the hydrophobic domain transforms into the hydrophilic one and the embedded DOX is released effectively. An increasing release ratio of DOX dramatically enhances the apoptosis ratio of HeLa cells. We expect these attractive properties may be beneficial to practical applications of the hydrogel as an effective local drug delivery means in a truly physiological environment.
Design, synthesis, biological screening and molecular docking studies of novel multifunctional 1,4-di (aryl/heteroaryl) substituted piperazine derivatives as potential antitubercular and antimicrobial agents
Mekonnen Sanka, Bruktawit,Mamo Tadesse, Dereje,Teju Bedada, Endale,Mengesha, Ephriem T.,Babu G., Neelaiah
, (2022/01/20)
In this paper, two series of novel multifunctional 1, 4-di (aryl/heteroaryl) substituted piperazine derivatives (6a-d & 7a-d) were synthesized, characterized, and evaluated for their antitubercular, antibacterial, and antifungal activities. A step-wise reduction, bromination and substitution reactions on various aldehydes resulted in alcohols (2a–d), bromides (3a–d), and titled novel compounds (6a–d & 7a–d) in moderate to good yields (48–85%). The novel compounds were evaluated for their antitubercular and antimicrobial activities. Compound 7a exhibited promising antitubercular activity (MIC: 0.65 μg/mL) almost equal to the Rifampicin, while the rest of the compounds were moderately active against MTB H37Rv except 6b. Compounds 7a and 6b showed good activity against tested fungal pathogens. Compounds 7a and 7b were proven as the best bacterial agents. Molecular docking studies were in agreement with the in-vitro results. Docking analyses show that all the synthesized molecules bind to the target protein Mtb RNAP (PDB ID: 5UHC) fairly strongly. All the compounds were evaluated for their in vitro cytotoxicity effect using the MTT assay method against human cancer cell line MCF-7. The compounds demonstrated growth inhibitory effect on the cell line with significant IC50 values ranging between 8.20 and 34.45 μM. Most importantly, compound 7a displayed good binding affinity towards the tested protein with binding energy ?7.30 kcal/mol and a stronger hydrogen bond distance of 2.2 ? with ASN-493 residue. Thus, the present research highlighted the potential role of novel piperazine derivatives as potential antitubercular, and antimicrobial candidates and further good research into optimization might result in the development of new antitubercular drug candidates.
Ethylene homo- and copolymerization catalyzed by vanadium, zirconium, and titanium complexes having potentially tridentate Schiff base ligands
Bia?ek, Marzena,Fryga, Julia,Hajdasz, Natalia,Matsko, Mikhail A.,Spaleniak, Grzegorz
, p. 184 - 194 (2021/07/09)
New potentially tridentate Schiff base ligands, 2-[({4-[(3-N,N-dimethylamino)propyl] phenyl}imino)methyl]-4,6-di-tert-butylphenol (L1H) and 2-[{2-(N-phenyl-N-methylaminomethyl)-phenylimino}-methyl]-4,6-di-tert-butylophenol (L2H) were prepared and after deprotonation they were reacted with VOCl3 or MCl4 (where M = Zr or Ti) to produce corresponding complexes (L1-V, L2-V, L1-Zr, L2-Ti) with good yields. All new compounds were characterized by the 1H and 13C NMR as well as FTIR spectroscopic methods. Upon activation with Et2AlCl or EtAlCl2, both the vanadium complexes exhibited exceptionally high catalytic activities in the ethylene polymerization (up to 69,000 kg/(molV?h) for L1-V and 101,500 kg/(molV?h) for L2-V) and remarkable thermal stability, and they produced UHMWPE. The complexes of group 4 metals were tested in the ethylene polymerization in conjunction with MMAO and Al(iBu)3/Ph3CB(C6F5)4, and L1-Zr was highly active (11,300 kg/(molZr?h)) and L2-Ti was moderately active (750 kg/(molTi?h)) when activated with MMAO. Furthermore, L1-2-V/EtAlCl2 systems were found to be very efficient in 1-octene incorporation and they produced copolymers with narrow chemical composition distributions and very narrow molecular weight distributions (Mw/Mn ≈ 2). In contrast to them, the catalysts based on titanium and zirconium complexes in conjunction with Al(iBu)3/Ph3CB(C6F5)4 gave copolymers with very broad comonomer and molecular weight distributions as well as with high molecular weights (Mw = 440,000–690,000 g/mol). It was also found that the chain transfer mechanism involved in the copolymerization process in the presence of vanadium and group 4 metal complexes was different.
NovelN-transfer reagent for converting α-amino acid derivatives to α-diazo compounds
Lu, Guan-Han,Huang, Tzu-Chia,Hsueh, Hsiao-Chin,Yang, Shin-Cherng,Cho, Ting-Wei,Chou, Ho-Hsuan
supporting information, p. 4839 - 4842 (2021/05/25)
A novel universalN-transfer reagent for direct and effective transformation of α-amino ketones, acetamides, and esters to the corresponding α-diazo products under mild basic conditions has been developed. This one-step synthetic approach not only allows for generation of α-substituted-α-diazo carbonyl compounds from α-amino acid derivatives but also permits preparation of α-diazo dipeptides fromN-terminal dipeptides (32 examples, up to 91%).
N-transfer reagent and method for preparing the same and its application
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Page/Page column 16-17, (2021/06/25)
Provided are a novel N-transfer reagent and a method for preparing the same and its application. The N-transfer reagent is represented by the following Formula (I): The various novel N-transfer reagents of the present invention can be quickly prepared by employing different nitrobenzene precursors. The N-transfer reagents can directly convert a variety of amino compounds into diazo compounds under mild conditions. Particularly, the N-transfer reagents can facilitate the synthesis of the diazo compounds. The application of synthesizing diazo compounds of the present invention can greatly decrease the difficulty in operation, increase the safety during experiments, reduce the cost of production and the environmental pollution, and enhance the industrial value of diazo compounds.
Method for preparing O-nitrobenzyl bromide by micro-channel reactor
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Paragraph 0030-0051, (2020/06/16)
The invention discloses a method for preparing o-nitrobenzyl bromide by a micro-channel reactor. According to the preparation method, o-nitrotoluene as a raw material and bromine as a bromine source react through a micro-channel reactor under the initiation of a catalyst to generate o-nitrobenzyl bromide. The method has the advantages of high production efficiency, high purity, simplicity and convenience in operation, safety and the like, and is suitable for industrial production.
Preparation method of O-nitrobenzyl bromide
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Paragraph 0018-0025, (2020/07/31)
The invention discloses a preparation method of nitrobenzyl bromide. The preparation method comprises the following steps of: step 1, dissolving ortho-nitrotoluene in halohydrocarbon, sequentially adding a hydrogen bromide solution, an initiator and lewis acid, continuing stirring and heating for backflow reaction, and step 2, dropwise adding a hydrogen peroxide solution into a reaction system instep 1 at a speed of 1-2 drops per min, after the backflow reaction for 1-3h, performing natural cooling, stopping stirring, and performing separation to form an organic phase, namely nitrobenzyl bromide. The method takes ortho-nitrotoluene as a raw material and hydrogen bromide as a bromine source; the hydrogen peroxide solution is added as an oxidant; the initiator and lewis acid are added for ortho-nitrotoluene bromination reaction to generate nitrobenzyl bromide; the preparation method is easy and simple to operate and high in yield; and a content of a byproduct, namely o-nitrocyclite is low.
Design, synthesis and biological evaluation of novel 3,4-dihydro-2(1H)-quinolinone derivatives as potential chitin synthase inhibitors and antifungal agents
Ji, Qinggang,Li, Baihui,Shen, Yangli,Wu, Hu,Wu, Xiaobo,Yuan, Lvjiang
supporting information, (2020/04/15)
A series of 3,4-dihydro-2(1H)-quinolinone derivatives contained butenediamide fragment were designed and synthesized. Their inhibition potency against chitin synthase and antimicrobial activities were screened in vitro. The enzymatic assays showed that all the synthesized compounds had inhibition potency against chitin synthase at concentration of 300 μg/mL. Compound 2d displayed excellent potency with inhibition percentage (IP) value of 82.3%, while IP value of the control polyoxin B was 87.5%. Compounds 2b, 2e and 2s whose IP values were above 70% showed good inhibition potency against chitin synthase. Moreover, the IC50 value of 2b was comparable with that of polyoxin B (0.09 mM). The Ki of compound 2b was 0.12 mM and the result from Lineweaver-Burk plot showed that 2b was non-competitive inhibitor to bind chitin synthase. The antifungal experiment showed that these compounds had excellent antifungal activity against fungal strains, especially for candida albicans. The antifungal activities against C .albicans of compounds 2b, 2d, 2e and 2l were comparable with that of fluconazole and were superior to that of polyoxin B. Meanwhile, the other compounds against C. albicans showed better antifungal activity (MIC 2 μg/mL) than polyoxin B except for compound 2n (MIC 4 μg/mL). The trial of drug combination use showed that these synthesized compounds had synergistic effects with fluconazole and polyoxin B. It indicated that these compounds were not competing with polyoxin B to bind with chitin synthase, which was also consistence with the result of enzymatic assays. The antibacterial experiment showed that these compounds had no activity against selected strains including three Gram-positive and three Gram-negative bacteria. These results showed that the designed compounds were chitin synthase inhibitors and had selective antifungal activity.
Thiourea-Mediated Halogenation of Alcohols
Mohite, Amar R.,Phatake, Ravindra S.,Dubey, Pooja,Agbaria, Mohamed,Shames, Alexander I.,Lemcoff, N. Gabriel,Reany, Ofer
, p. 12901 - 12911 (2020/11/26)
The halogenation of alcohols under mild conditions expedited by the presence of substoichiometric amounts of thiourea additives is presented. The amount of thiourea added dictates the pathway of the reaction, which may diverge from the desired halogenation reaction toward oxidation of the alcohol, in the absence of thiourea, or toward starting material recovery when excess thiourea is used. Both bromination and chlorination were highly efficient for primary, secondary, tertiary, and benzyl alcohols and tolerate a broad range of functional groups. Detailed electron paramagnetic resonance (EPR) studies, isotopic labeling, and other control experiments suggest a radical-based mechanism. The fact that the reaction is carried out at ambient conditions, uses ubiquitous and inexpensive reagents, boasts a wide scope, and can be made highly atom economic, makes this new methodology a very appealing option for this archetypical organic reaction.
Preparation method of O-nitryl phenmethyl bromine (by machine translation)
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Paragraph 0028-0075; 0078, (2019/03/08)
The invention discloses a O-nitryl phenmethyl bromine of the preparation method, the preparation method is to O-nitro-toluene as the raw materials, to NaClO/HBr as the brominating agent, in the azo azobisisobutyronitrile as initiator of the initiation action through the brominating reaction to obtain O-nitryl phenmethyl bromine. Preparation method of this invention, to the O-nitryl phenmethyl bromine as a brominating NaClO/HBr, raw materials are easy, and the cost is low, and the process is simple, the operation is simple, mild reaction conditions, the higher selectivity of the reaction, the reaction yield>72% (in order to O-nitro-toluene idea), solid product after the purification processing in the content of the O-nitryl phenmethyl bromine>97%, suitable for industrialization to popularize. (by machine translation)
