13139-15-6Relevant articles and documents
Synthesis, antimicrobial potency with in silico study of Boc-leucine-1,2,3-triazoles
Ghule, Vikas D.,Kumar, Ashwani,Lal, Kashmiri,Naveen,Tittal, Ram Kumar,Yadav, Pinki
, (2020)
A library of N-Boc protected Leucine-linked 1,4-disubstituted 1,2,3-triazoles was synthesized and fully characterized, in high yield via copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction. In vitro antibacterial activity showed that compound 4h found to be more potent than the reference drug Ciprofloxacin (MIC: 0.0196 μmol/mL) against tested bacterial strains S. entrica, B. subtilis, S. aureus, E. coli and P. auroginosa with MIC: 0.0148, 0.0074, 0.0148, 0.0074, and 0.0074 μmol/mL, respectively and antifungal activity with MIC: 0.0148 μmol/mL as compared to reference drug Fluconazole (MIC: 0.0102 μmol/mL) against A. niger and C. albicans fungal strains. Further, the molecular docking study on 4h and its predecessor alkyne 3 by choosing E. coli topoisomerase II, DNA Gyrase (PDB ID: 1KZN) showed better binding with triazole than alkyne and these results were supported by DFT study using B3LYP/6-311G(d,p) basis set.
Optical resolution of N-(t-butoxycarbonyl)leucine through mixed ligand complex formation with (R)-N-(2-pyridylmethyl)pipecolatocopper(II)
Yajima, Tatsuo,Fukushima, Takeo,Yamada, Atsuya,Shiraiwa, Tadashi
, p. 451 - 455 (2017)
A copper(II) complex of (R)-N-(2-pyridylmethyl)pipecolate (pmpi) was prepared, and its structure was revealed by X-ray crystal structure analysis. Mixed ligand complexes were then prepared from this complex and (R)- and (S)-N-(t-butoxycarbonyl)leucinate (BocLeu). The (R)-BocLeu complex is less soluble in aqueous acetonitrile and more soluble in acetone than the (S)-BocLeu complex, and the reason was discussed on the basis of their structures. Recrystallization of the reaction mixture consisting of Cu(II) ion, pmpi, and (RS)-BocLeu from aqueous acetonitrile gave the (R)-BocLeu complex and that from acetone gave the (S)-BocLeu complex.
Synthesis, in vitro and in vivo biological evaluation of dihydroartemisinin derivatives with potential anti-Toxoplasma gondii agents
Deng, Hao,Huang, Xing,Jin, Chun-Mei,Jin, Chunmei,Quan, Zhe-Shan
, (2020)
In this study, four series of dihydroartemisinin derivatives were designed, synthesized, and evaluated for anti-toxoplasma gondii activity, and calculated the selectivity index (SI). It was the higher the SI, the better the effect of this compound against Toxoplasma gondii. Our goal was to filter out compounds that were bigger SI than the lead compound. The compound with the highest SI was selected for the anti-toxoplasmosis test in mice in vivo. Among the synthesized compounds, the (3R,5aS,6R,8aS,9R,12R,12aR)-3,6,9-trimethyl-decahydro-12H-3,12-epoxy[1,2]di-oxepino[4,3 -i]isochromen-10-yl-(te-rt-butoxycarbonyl)-L-alaninate (A2) exhibited the most potent anti-T. gondii activity and low cytotoxicity (SI: 6.44), yielding better results than the lead compound DHA (SI: 1.00) and the clinically used positive-control drug spiramycin (SI: 0.72) in vitro. Furthermore, compound A2 had better growth inhibitory effects on T. gondii in vivo than spiramycin did and significantly reduced the number of tachyzoites in the peritoneal cavity of mice (P 0.01). The evaluation of the data generated in the T. gondii mouse infection model indicates that compound A2 treatment was a good inhibitor of T. gondii in vivo and that it was effective in relieving the liver damage induced by T. gondii. In addition, the results of a docking study revealed that A2 could become a better T. gondii calcium-dependent protein kinase1 (TgCDPK1) inhibitor. For this reason, compound A2 has potential as an anti-parasitic drug. Further studies are required to elucidate the mechanism of the action of compound A2, as well as to develop drug delivery systems for patients.
Synthesis and antibacterial activity of amino acid and dipeptide prodrugs of IMB-070593, a fluoroquinolone candidate
Zhang, Tingting,Wu, Jinwei,Chen, Shihong,Liu, Kaixiang,Lin, Yabin,Guo, Huiyuan,Liu, Mingliang
, p. 6822 - 6837 (2014)
A series of amino acid and dipeptide prodrugs of IMB-070593, a fluoroquinolone candidate discovered in our lab, were synthesized and evaluated for their water solubility and then antibacterial activity. Our results reveal that four amino acid prodrugs 4a,b,e,f and two dipeptide prodrugs 4k,l have much greater solubility (>85 mg/mL) than IMB-070593 mesylate (22.5 mg/mL). Compounds 4a and 4k show good in vivo efficacy against MSSA 12-1 (p.o./i.v., 5.32-7.68 mg/kg) and S. pneumoniae12-10 (p.o., 18.39-23.13 mg/kg) which is 1.19-1.50 fold more active than the parent drug.
Synthesis and bioactivities study of new antibacterial peptide mimics: The dialkyl cationic amphiphiles
Zhang, En,Bai, Peng-Yan,Cui, De-Yun,Chu, Wen-Chao,Hua, Yong-Gang,Liu, Qin,Yin, Hai-Yang,Zhang, Yong-Jie,Qin, Shangshang,Liu, Hong-Min
, p. 1489 - 1509 (2018)
The emergence of infectious diseases caused by pathogenic bacteria is widespread. Therefore, it is urgently required to enhance the development of novel antimicrobial agents with high antibacterial activity and low cytotoxicity. A series of novel dialkyl cationic amphiphiles bearing two identical length lipophilic alkyl chains and one non-peptidic amide bond were synthesized and tested for antimicrobial activities against both Gram-positive and Gram-negative bacteria. Particular compounds synthesized showed excellent antibacterial activity toward drug-sensitive bacteria such as S. aureus, E. faecalis, E. coli and S. enterica, and clinical isolates of drug-resistant species such as methicillin-resistant S. aureus (MRSA), KPC-producing and NDM-1-producing carbapenem-resistant Enterobacteriaceae (CRE). For example, the MIC values of the best compound 4g ranged from 0.5 to 2 μg/mL against all these strains. Moreover, these small molecules acted rapidly as bactericidal agents, and functioned primarily by permeabilization and depolarization of bacterial membranes. Importantly, these compounds were difficult to induce bacterial resistance and can potentially combat drug-resistant bacteria. Thus, these compounds can be developed into a new class of antibacterial peptide mimics against Gram-positive and Gram-negative bacteria, including drug-resistant bacterial strains.
D-amino acid position influences the anticancer activity of galaxamide analogs: An apoptotic mechanism study
Bai, Defa,Yu, Siming,Zhong, Shenghui,Zhao, Bingxin,Qiu, Shaoling,Chen, Jianwei,Lunagariya, Jignesh,Liao, Xiaojian,Xu, Shihai
, (2017)
Galaxamide, an extract from Galaxaura filamentosa, is a cyclic pentapeptide containing five L-leucines. Due to the particular cyclic structure and the excellent anticancer activity, synthesis of Galaxamide and its analogs and their subsequent bio-applications have attracted great attention. In the present work, we synthesized six Galaxamide analogs by replacing one of the L-leucines with phenylalanine and varying the D-amino acid position. The anticancer effect of the synthesized Galaxamide analogs was tested against four in vitro human cancer cell lines, human hepatocellular cells (HepG2), human breast cancer cell (MCF-7), human breast adenocarcinoma cells (MDA-MB-435) and a human cervical carcinoma cell line (Hela). Results showed that Galaxamide analogs with differentD-amino acid positions displayed distinct anticancer potential. The Galaxamide analog containing D-amino acid at position 5 (Analog-6) presented the strongest anticancer activity. The mechanism study revealed that Analog-6 could cause the early apoptosis of HepG2 cells by inhibiting their growth in the sub-G1 stage of the cell cycle and induce the chromatin condensation and fragmentation, which can be seen as 68% of HepG2 cells inhibited in the sub-G1 stage. Moreover, a mitochondria-mediated pathway was found to be involved in the apoptotic process of Analog-6 on HepG2 cells.
DNA-directed formation of peptide bond: A model study toward DNA-programmed peptide ligation
Zhang, Chi,Li, Yizhou,Zhang, Mingda,Li, Xiaoyu
, p. 5152 - 5156 (2012)
A model study of DNA-directed peptide ligation has been developed by transferring fluorescent reporting group from small molecule thioester to a DNA strand (template DNA) in the presence of a thiol-functionalized DNA strand (auxiliary DNA), mimicking the Native Chemical Ligation (NCL) reaction. This DNA-directed transfer shows dependence on the sequence complementarity of the two DNA strands, with in situ generated 4-thiolphenylmethyl functionalized oligonucleotide as the auxiliary DNA strand, under mild basic condition (pH=8.5), and with tris(2-carboxyethyl) phosphine hydrochloride (TCEP) as a reducing agent. Reactions with different amino acid α-thioesters resulted in varied transfer efficiencies from glycine to α-substituted amino acids. This study has provided the basic foundation to use DNA-programmed chemistry toward the chemical synthesis or unnatural modification of protein molecules.
Water-soluble gambogic acid PEGylated prodrugs: Synthesis, characterization, physicochemical properties and in vitro hydrolysis
Tang, Xiaoyan,Zhang, Peng,Ye, Hai,Zhang, Can,Shen, Wenbin,Ping, Qineng
, p. 711 - 717 (2008)
A series of poly(ethylene glycol) (PEG) prodrugs of gambogic acid (GA) with different molecular weight which used L-leucine as spacer were synthesized and characterized by FT-IR, 1H NMR and TOF MS. Drug loading capability, analyzed by UV spectrum, was 17.48, 9.26, 3.99, and 1.79%, aqueous solubility of the prodrugs was determined to be 1750, 1250, 800, and 645 mg/ml, respectively. The drug release from prodrugs was investigated under simulated in vivo conditions whose half-time (t1/2) in plasma ranged from 1.26 to 6.12 h. The effect of temperature on drug release was studied at four different temperatures and activation energy was determined as well. The stability of the prodrugs was improved in parallel with increasing molecular weight of PEG while prodrug yields and drug loading capability were reduced.
Synthesis of pyrimidine nucleoside and amino acid conjugates
Koplūnait?, Martyna,Butkut?, Kamil?,Me?kys, Rolandas,Taurait?, Daiva
, (2020)
The synthesis of novel pyrimidine nucleoside bioconjugates with amino acids is presented. The N4-amino acid-acylated 2′-deoxycytidine analogues, modified with various amino acids, were synthesized using a three-step synthesis and obtained in moderate overall yields. Novel amino acid-alkylated 2′-deoxycytidine derivatives were obtained during the rearrangement of amino acid-acylated derivatives that occurred during Boc deprotection.
Enantioselective Deaminative Alkylation of Amino Acid Derivatives with Unactivated Olefins
Cai, Yue-Ming,Martin, Ruben,Rui, Xi-Yan,Shang, Ming,Sun, Shang-Zheng,Wang, Jia-Bao,Yao, Hong-Qing,Zhang, De-Liang
supporting information, p. 1130 - 1137 (2022/02/05)
Herein, we report the first Ni-catalyzed enantioselective deaminative alkylation of amino acid and peptide derivatives with unactivated olefins. Key for success was the discovery of a new sterically encumbered bis(oxazoline) ligand backbone, thus offering a de novo technology for accessing enantioenriched sp3-sp3 linkages via sp3 C-N functionalization. Our protocol is distinguished by its broad scope and generality across a wide number of counterparts, even in the context of late-stage functionalization. In addition, an enantioselective deaminative remote hydroalkylation reaction of unactivated internal olefins is within reach, thus providing a useful entry point for forging enantioenriched sp3-sp3 centers at remote sp3 C-H sites.
