640-68-6Relevant academic research and scientific papers
Polyketides, diketopiperazines and an isochromanone from the marine-derived fungal strain Fusarium graminearum FM1010 from Hawaii
Cao, Shugeng,Sarotti, Ariel M.,Uz Zaman, KH Ahammad,Wu, Xiaohua
, (2022/03/09)
The fungal strain Fusarium graminearum FM1010 was isolated from a shallow-water volcanic rock known as “live rock” at the Carl Smith Beach, Hilo, Hawaii. Eleven specialised metabolites, including two undescribed diketopiperazines, three undescribed polyketides, and one undescribed isochromanone, along with five known fusarielin derivatives were obtained from F. graminearum FM1010. The structures of the six undescribed compounds were elucidated by extensive analysis of NMR spectroscopy, HRESIMS, chemical reactions, and electronic circular dichroism (ECD) data. Kaneoheoic acids G-I showed mild inhibitory activity against S. aureus with the MIC values in the range of 20–40 μg/mL when assayed in combination with chloramphenicol (half of the MIC, 1 μg/mL), an FDA approved antibiotic. Kaneoheoic acid I exhibited both anti-proliferative activity against ovarian cancer cell line A2780 and TNF-α induced NF-κB inhibitory activity with the IC50 values of 18.52 and 15.86 μM, respectively.
Single-Cell-Based Screening and Engineering of d -Amino Acid Amidohydrolases Using Artificial Amidophenol Substrates and Microbial Biosensors
An, Jung-Ung,Kim, Haseong,Kwon, Kil Koang,Lee, Dae-Hee,Lee, Hyewon,Lee, Jin-Young,Lee, Seung-Goo,Park, Sung Hyun,Rha, Eugene,Yeom, Soo-Jin
, p. 1203 - 1211 (2022/01/27)
Enantiomerically pure d-amino acids are important intermediates as chiral building blocks for peptidomimetics and semisynthetic antibiotics. Here, a transcriptional factor-based screening strategy was used for the rapid screening of d-stereospecific amino acid amidase via an enzyme-specific amidophenol substrate. We used a d-threonine amidophenyl derivative to produce 2-aminophenol that serves as a putative enzyme indicator in the presence of d-threonine amidases. Comparative analyses of known bacterial species indicated that several Bacillus strains produce amidase and form putative indicators in culture media. The estimated amidase was cloned and subjected to rapid directed evolution through biosensor cells. Consequently, we characterized the F119A mutation that significantly improved the catalytic activity toward d-alanine, d-threonine, and d-glutamate. Its beneficial effects were confirmed by higher conversions and recurrent applications of the mutant enzyme, compared to the wild-type. This study showed that rapid directed evolution with biosensors coupled to designed substrates is useful to develop biocatalytic processes.
Inherently chiral dialkyloxy-calix[4]arene acetic acids as enantiodiscriminating additives for high-performance liquid chromatography separation of d,l-amino acids
Kalchenko, Olga I.,Trybrat, Oleksandr O.,Yesypenko, Oleksandr A.,Dyakonenko, Viktoriya V.,Shishkina, Svitlana V.,Kalchenko, Vitali I.
, p. 722 - 730 (2021/08/26)
Inherently chiral dialkyloxy-calix[4]arene acetic acids with asymmetric placement of substituents on the lower rim of the macrocycle were first studied as enantiodiscriminating additives to the mobile phase MeCN/H2O/HCOOH (75/25/0.02 by volume) in the high-performance liquid chromatography (HPLC) separation of d,l-alanine and d,l-valine on the achiral stationary phase ZORBAX Original CN. The dependence of enantio-binding properties on the position of alkyl groups is demonstrated. The highest resolution (1.65) and enantioselectivity (1.80) were obtained for the 1,2-dipropyloxy-calix[4]arene acetic acid.
Targeted Isolation of Asperheptatides from a Coral-Derived Fungus Using LC-MS/MS-Based Molecular Networking and Antitubercular Activities of Modified Cinnamate Derivatives
Chao, Rong,Hou, Xue-Mei,Xu, Wei-Feng,Hai, Yang,Wei, Mei-Yan,Wang, Chang-Yun,Gu, Yu-Cheng,Shao, Chang-Lun
, p. 11 - 19 (2021/01/14)
Under the guidance of MS/MS-based molecular networking, four new cycloheptapeptides, namely, asperheptatides A-D (1-4), were isolated together with three known analogues, asperversiamide A-C (5-7), from the coral-derived fungus Aspergillus versicolor. The planar structures of the two major compounds, asperheptatides A and B (1 and 2), were determined by comprehensive spectroscopic data analysis. The absolute configurations of the amino acid residues were determined by advanced Marfey's method. The two structurally related trace metabolites, asperheptatides C and D (3 and 4), were characterized by ESI-MS/MS fragmentation methods. A series of new derivatives (8-26) of asperversiamide A (5) were semisynthesized. The antitubercular activities of 1, 2, and 5-26 against Mycobacterium tuberculosis H37Ra were also evaluated. Compounds 9, 13, 23, and 24 showed moderate activities with MIC values of 12.5 μM, representing a potential new class of antitubercular agents.
Simultaneous Preparation of (S)-2-Aminobutane and d -Alanine or d -Homoalanine via Biocatalytic Transamination at High Substrate Concentration
Li, Jianjiong,Wang, Yingang,Wu, Qiaqing,Yao, Peiyuan,Yu, Shanshan,Zhu, Dunming
supporting information, (2022/03/01)
(S)-2-Aminobutane, d-alanine, and d-homoalanine are important intermediates for the production of various active pharmaceutical ingredients and food additives. The preparation of these small chiral amine or amino acids with high water solubility still demands searching for efficient methods. In this work, we identified an ω-transaminase (ω-TA) from Sinirhodobacter hungdaonensis (ShdTA) that catalyzed the kinetic resolution of racemic 2-aminobutane at a concentration of 800 mM using pyruvate as the amino acceptor, leading to the simultaneous isolation of enantiopure (S)-2-aminobutane and d-alanine in 46% and 90% yield, respectively. In addition, (S)-2-aminobutane (98% ee) and d-homoalanine (99% ee) were isolated in 45% and 93% yield, respectively, in the kinetic resolution of racemic 2-aminobutane at a concentration of 400 mM coupled with deamination of l-threonine by threonine deaminase. We thus developed a biocatalytic process for the practical synthesis of these valuable small chiral amine and d-amino acids.
A new amide from the marine sponge Haliclona baeri
Cui, Le-Zhi,Lei, Yu,Liao, Xiao-Jian,Wang, Can-Bin,Xiao, Yan-Fang,Xu, Jia-Yi,Xu, Shi-Hai,Zhao, Bing-Xin
supporting information, (2021/07/06)
A new amide, baeriamide (1), along with nine known diketopiperazines (2-10), was isolated from the marine sponge Haliclona baeri. Their structures were identified by the means of UV, IR, MS and NMR. The absolute configuration of 1 was established by Marfey’s method and comparing the specific optical rotation with the known compound HCO-Val-Gly methyl ester. Compound 1 was derived from dehydration of formylated L-valine with γ-amino-butanoic acid methyl ester. Compounds 2-10 were isolated from the genus of Haliclona for the first time. The absolute confirmation of 7 was confirmed first by the means of single-crystal X-ray diffraction. The cytotoxic, antibacterial, antiviral and antifouling activities of these compounds were also tested. However, none of them exhibited significant bioactivities.
Exploration of Transaminase Diversity for the Oxidative Conversion of Natural Amino Acids into 2-Ketoacids and High-Value Chemicals
Chen, Yanchun,Cui, Xuexian,Cui, Yinglu,Li, Chuijian,Li, Ruifeng,Li, Tao,Sun, Jinyuan,Wu, Bian,Zhu, Tong
, p. 7950 - 7957 (2020/08/21)
The use of 2-ketoacids is very common in feeds, food additives, and pharmaceuticals, and 2-ketoacids are valuable precursors for a plethora of chemically diverse compounds. Biocatalytic synthesis of 2-ketoacids starting from l-amino acids would be highly desirable because the substrates are readily available from biomass feedstock. Here, we report bioinformatic exploration of a series of aminotransferases (ATs) to achieve the desired conversion. Thermodynamic control was achieved by coupling an l-glutamate oxidation reaction in the cascade for the recycling of the amine acceptor. These enzymes were able to convert a majority of proteinogenic amino acids into the corresponding 2-ketoacids with high conversion (up to 99percent) and atom-efficiency. Furthermore, this enzyme cascade was extendable, and one-pot two-step processes were established for the synthesis of d-amino acids and N-methylated amino acids, achieving great overall conversion (up to 99percent) and high ee values (>99percent). These developed enzymatic methodologies offer convenient routes for utilizing amino acids as synthetic reagents.
Krisynomycins, Imipenem Potentiators against Methicillin-Resistant Staphylococcus aureus, Produced by Streptomyces canus
De La Cruz, Mercedes,Genilloud, Olga,González, Ignacio,Martín, Jesús,Oves-Costales, Daniel,Pérez-Bonilla, Mercedes,Reyes, Fernando,Vicente, Francisca
, p. 2597 - 2606 (2020/10/12)
A reinvestigation of the acetone extract of the strain CA-091830 of Streptomyces canus, producer of the imipenem potentiator krisynomycin, resulted in the isolation of two additional analogues, krisynomycins B (1) and C (2), with different chlorination patterns. Genome sequencing of the strain followed by detailed bioinformatics analysis led to the identification of the corresponding biosynthetic gene cluster (BGC) of this cyclic nonribosomal peptide family. The planar structure of the new molecules was determined using HRMS, ESI-qTOF-MS/MS, and 1D and 2D NMR data. Their absolute configuration was proposed using a combination of Marfey's and bioinformatic BGC analyses. The krisynomycins displayed weak to negligible antibiotic activity against methicillin-resistant Staphylococcus aureus (MRSA), which was significantly enhanced when tested in combination with sublethal concentrations of imipenem. The halogenation pattern plays a key role in the antimicrobial activity and imipenem-potentiating effects of the compounds, with molecules having a higher number of chlorine atoms potentiating the effect of imipenem at lower doses.
Homogeneous palladium-catalyzed enantioselective hydrogenation of 5-methylenhydantoin for the synthesis of L-Valine
Agbossou-Niedercorn, Francine,Bellière-Baca, Virginie,Hayouni, Safa,Michon, Christophe,Morvan, Didier
supporting information, (2020/10/18)
In this article, we present the development of a synthetic methodology based on homogeneous catalysis for the preparation of enantioenriched L-Valine aminoacid. The enantioselective hydrogenation of 5-methylenhydantoin has been developed through broad screenings of chiral ligands, metal precursors and reaction conditions including scale-up experiments and recyclability studies. A palladium catalyzed asymmetric hydrogenation of 5-methylenhydantoin afforded the corresponding hydrogenated product in a 70% enantiomeric excess using a substrate/catalyst ratio of 500/1. A partial racemization was observed upon hydrolysis and recovery of L-Valine.
Preparation and characterization of a new open-tubular capillary column for enantioseparation by capillary electrochromatography
Li, Yingjie,Tang, Yimin,Qin, Shili,Li, Xue,Dai, Qiang,Gao, Lidi
, p. 283 - 292 (2019/02/05)
In order to use the enantioseparation capability of cationic cyclodextrin and to combine the advantages of capillary electrochromatography (CEC) with open-tubular (OT) column, in this study, a new OT-CEC, coated with cationic cyclodextrin (1-allylimidazolium-β-cyclodextrin [AI-β-CD]) as chiral stationary phase (CSP), was prepared and applied for enantioseparation. Synthesized AI-β-CD was characterized by infrared (IR) spectrometry and mass spectrometry (MS). The preparation conditions for the AI-β-CD-coated column were optimized with the orthogonal experiment design L9(34). The column prepared was characterized by scanning electron microscopy (SEM) and elemental analysis (EA). The results showed that the thickness of stationary phase in the inner surface of the AI-β-CD-coated columns was about 0.2 to 0.5?μm. The AI-β-CD content in stationary phase based on the EA was approximately 2.77?mmol·m?2. The AI-β-CD-coated columns could separate all 14 chiral compounds (histidine, lysine, arginine, glutamate, aspartic acid, cysteine, serine, valine, isoleucine, phenylalanine, salbutamol, atenolol, ibuprofen, and napropamide) successfully in the study and exhibit excellent reproducibility and stability. We propose that the column, coated with AI-β-CD, has a great potential for enantioseparation in OT-CEC.
