425-75-2Relevant academic research and scientific papers
Synthesis and bioactivity investigation of quinone-based dimeric cationic triazolium amphiphiles selective against resistant fungal and bacterial pathogens
Shrestha, Jaya P.,Baker, Coleman,Kawasaki, Yukie,Subedi, Yagya P.,Vincent de Paul, Nzuwah Nziko,Takemoto, Jon Y.,Chang, Cheng-Wei Tom
, p. 1 - 17 (2017)
A series of synthetic dimeric cationic anthraquinone analogs (CAAs) with potent antimicrobial activities against a broad range of fungi and bacteria were developed. These compounds were prepared in 2–3 steps with high overall yield and possess alkyl chain, azole, quinone, and quaternary ammonium complexes (QACs). In vitro biological evaluations reveal prominent inhibitory activities of lead compounds against several drug-susceptible and drug-resistant fungal and bacterial strains, including MRSA, VRE, Candida albicans and Aspergillus flavus. Mode of action investigation reveals that the synthesized dimeric CAA's can disrupt the membrane integrity of fungi. Computational studies reveal possible designs that can revive the activity of QACs against drug-resistant bacteria. Cytotoxicity assays in SKOV-3, a cancer cell line, show that the lead compounds are selectively toxic to fungi and bacteria over human cells.
Synthesis, characterization, and reaction studies of pd(Ii) tripeptide complexes
Bjornsson, Ragnar,Monger, Lindsey J.,Razinkov, Dmitrii,Suman, Sigridur G.
, (2021/09/04)
The aqueous synthesis of Pd(II) complexes with alkylated tripeptides led to the hydrolysis of the peptides at low pH values and mixtures of complexed peptides were formed. A non-aqueous synthetic route allowed the formation and isolation of single products and their characterization. Pd(II) complexes with α-Asp(OR)AlaGly(OR), β-Asp(OR)AlaGly(OR), and TrpAlaGly(OR) (R = H or alkyl) as tri and tetradentate chelates were characterized. The tridentate coordination mode was accompanied by a fourth monodentate ligand that was shown to participate in both ligand exchange reactions and a direct removal to form the tetradentate coordination mode. The tetradentate coordination revealed a rare a hemi labile carbonyl goup coordination mode to Pd(II). Reactivity with small molecules such as ethylene, acids, formate, and episulfide was investigated. Under acidic conditions and in the presence of ethylene; acetaldehyde was formed. The Pd(II) is a soft Lewis acid and thiophilic and the complexes abstract sulfur from episulfide at apparent modest catalytic rates. The complexes adopt a square planar geometry according to a spectroscopic analysis and DFT calculations that were employed to evaluate the most energetically favorable coordination geometry and compared with the observed infrared and NMR data.
Lysine Ethylation by Histone Lysine Methyltransferases
Al Temimi, Abbas H. K.,Martin, Michael,Meng, Qingxi,Lenstra, Danny C.,Qian, Ping,Guo, Hong,Weinhold, Elmar,Mecinovi?, Jasmin
, p. 392 - 400 (2019/11/13)
Biomedicinally important histone lysine methyltransferases (KMTs) catalyze the transfer of a methyl group from S-adenosylmethionine (AdoMet) cosubstrate to lysine residues in histones and other proteins. Herein, experimental and computational investigations on human KMT-catalyzed ethylation of histone peptides by using S-adenosylethionine (AdoEth) and Se-adenosylselenoethionine (AdoSeEth) cosubstrates are reported. MALDI-TOF MS experiments reveal that, unlike monomethyltransferases SETD7 and SETD8, methyltransferases G9a and G9a-like protein (GLP) do have the capacity to ethylate lysine residues in histone peptides, and that cosubstrates follow the efficiency trend AdoMet>AdoSeEth>AdoEth. G9a and GLP can also catalyze AdoSeEth-mediated ethylation of ornithine and produce histone peptides bearing lysine residues with different alkyl groups, such as H3K9meet and H3K9me2et. Molecular dynamics and free energy simulations based on quantum mechanics/molecular mechanics potential supported the experimental findings by providing an insight into the geometry and energetics of the enzymatic methyl/ethyl transfer process.
Tuning the biological activity of cationic anthraquinone analogues specifically toward Staphylococcus aureus
Subedi, Yagya Prasad,Alfindee, Madher N.,Shrestha, Jaya P.,Chang, Cheng-Wei Tom
, p. 683 - 690 (2018/08/23)
Development of new antibacterial agents against drug resistant bacteria is an imminent task, especially against methicillin-resistant Staphylococcus aureus (MRSA). While MRSA can still be treated with broad spectrum antibiotics, the use of which often leads to the disruption of normal microbial flora leading to Clostridium difficile infection (CDI). Herein, a new class of antibacterial agent, cationic anthraquinone analogues specifically against MRSA, has been developed. Through the variation and optimization of substituents, these agents are selective toward MRSA, and not Gram negative bacteria which may avoid the problem of CDI. In addition, newly discovered lead compounds also show significantly reduced cytotoxicity against normal mammalian cells than cancerous cells. This interesting finding can alleviate the toxicity and side effect problems often associate with the use of antibiotics.
A continuous preparation method of triflic acid ethyl ester
-
Paragraph 0018; 0019, (2017/02/09)
A disclosed method for continuously preparing ethyl trifluoromethanesulfonate comprises the following steps: (1) adding trifluoromethanesulfonic acid and diethyl sulfate with the molar ratio of (1-2):1 into a reaction kettle, switching on a stirring apparatus, raising the temperature of the reaction kettle to 50-100 DEG C, and keeping the temperature for reacting for 2-6 h; and (2) raising the temperature of the reaction kettle to 100-150 DEG C, switching on a rectifying apparatus, controlling the reflux ratio of the rectifying apparatus at (1-3):(3-1), continuously introducing trifluoromethanesulfonic acid and diethyl sulfate into the reaction kettle, controlling the speed of trifluoromethanesulfonic acid introduced into the reaction kettle at 30-70 g/min, controlling the speed of diethyl sulfate introduced into the reaction kettle at 10-50 g/min, and collecting a distillation fraction and condensing to obtain ethyl trifluoromethanesulfonate. The preparation method is short in production period and low in energy consumption, and prepared ethyl trifluoromethanesulfonate has the purity larger than 99%, the yield is 90% or more, and industrialized production can be realized.
Anthraquinone Analogs
-
Page/Page column 17, (2012/03/09)
Anthraquinone analogs, methods for synthesizing anthraquinone analogs, and methods for inhibiting growth of one or more types of cells using anthraquinone analogs. Anthraquinone analogs can be synsthesized according to methods described herein. Optionally, the synthesis methods described herein include choosing an appropriate leaving group for selectively producing 1-alkyl-1H-naphtho[2,3-d]triazole-4,9-diones or 2-alkyl-2H-naphtho[2,3-d]triazole-4,9-diones. Anthraquinone analogs can include various functional groups that affect their ability to inhibit the growth of various cell types. For example, some anthraquinone analogs disclosed herein have antimicrobial activity while seemingly similar compounds demonstrate anticancer activity but lesser antimicrobial activity.
Library synthesis and antibacterial investigation of cationic anthraquinone analogs
Fosso, Marina Y.,Chan, Ka Yee,Gregory, Rylee,Chang, Cheng-Wei Tom
experimental part, p. 231 - 235 (2012/05/20)
We report the parallel synthesis of a series of novel 4,9-dioxo-4,9- dihydro-1H-naphtho[2,3-d][1,2,3]triazol-3-ium chloride salts, which are analogs to cationic anthraquinones. Three synthetic protocols were examined leading to a convenient and facile library synthesis of the cationic anthraquinone analogs that contain double alkyl chains of various lengths (C2-C 12) at N-1 and N-3 positions. The antibacterial activities of these compounds were evaluated against Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Escherichia coli. The antibacterial activities of these compounds were expected to be associated with the structural features of naphthoquinone, cation and lypophilic alkyl chain and, interestingly, they showed much higher levels of antibacterial activities against G+ than G- bacteria. In addition, when the total number of carbon atoms of the alkyl groups at both N-1 and N-3 positions lies between 9 and 18, the bactericidal activity against S. aureus increased with increasing alkyl chain length at both N-atoms with MIC ≥ 1 μg/mL.
A convenient synthesis of triflate anion ionic liquids and their properties
Ignat'ev, Nikolai V.,Barthen, Peter,Kucheryna, Andryi,Willner, Helge,Sartori, Peter
experimental part, p. 5319 - 5338 (2012/08/28)
A solvent- and halogen-free synthesis of high purity triflate ionic liquids via direct alkylation of organic bases (amines, phosphines or heterocyclic compounds) with methyl and ethyl trifluoromethanesulfonate (methyl and ethyl triflate) has been developed. Cheap and non-toxic dimethyl and diethyl carbonate serve as source for the methyl and ethyl groups in the preparation of methyl and ethyl triflate by this invented process. The properties of ionic liquids containing the triflate anion are determined and discussed.
Mode of action investigation for the antibacterial cationic anthraquinone analogs
Chan, Ka Yee,Zhang, Jianjun,Chang, Cheng-Wei Tom
supporting information; experimental part, p. 6353 - 6356 (2011/12/02)
Reported previously by our group, we have developed a novel class of antibacterial cationic anthraquinone analogs with superb potency (MIC 1 μg/mL) against Gram positive (G+) pathogens including Methicillin-resistant Staphylococcus aureus (MRSA). However, most of these compounds only manifest modest antibacterial activity against Gram negative (G-) bacteria. Further investigation on the antibacterial mode of action using fluorogenic dyes reveals that these compounds exert two different modes of action that account for the difference in their antibacterial profile. It was found that most of the compounds exert their antibacterial activity by disrupting the redox processes of bacteria. At high concentration, these compounds can also act as membrane disrupting agents. This information can help to design new therapeutics against various bacteria.
Synthesis of enantiopure 1-r-alkyl-2-c,5-t-diphenylphospholanes and phospholanium salts through direct alkylation of phospholane
Dobrota, Cristian,Duraud, Amelie,Toffano, Martial,Fiaud, Jean-Claude
body text, p. 2439 - 2445 (2009/04/10)
Chiral enantiopure 1-alkyl-2,5-diphenylphospholanium salts were obtained in one step through alkylation of phospholane with alkyl triflates. The resulting air-stable phosphonium salts are electron-rich trialkylphosphane precursor ligands for transition metals, and they offer a convenient route toward chiral quaternary phosphonium salts as phase-transfer agents. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
