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1. Antimicrobial use and practices by animal health professionals in 20 sub-Saharan African countries

Author:
Tebug, Stanly Fon; Mouiche, Mohamed Moctar Mouliom; Abia, Wilfred Angie; Teno, Gabriel; Tiambo, Christian Keambou; Moffo, Frédéric; Awah-Ndukum, Julius
Source:
Preventive veterinary medicine 2021 v.186 pp. 105212
ISSN:
0167-5877
Subject:
beta-lactams,   etc   ; animal health; animal production; antibiotic resistance; continuing education; disease diagnosis; education programs; gender; guidelines; information sources; macrolides; questionnaires; surveys; tetracycline; veterinarians; working conditions; Sub-Saharan Africa;     Show all 17 Subjects
Abstract:
... The use of antimicrobial (AM) in animal production is an important contributor to antimicrobial resistance (AMR) worldwide. Animal health professionals should play a key role in ensuring judicious use of AM. However, they are subjected to influence from clinical and non-clinical factors. The present study evaluates the perceptions and concerns of animal health practitioners regarding antimicrobial ...
DOI:
10.1016/j.prevetmed.2020.105212

2. Direct and practical Gilman-Speeter synthesis of 3,4-trisubstituted β-lactams via the Thorpe-Ingold effect

Author:
Panagiotou, Maria; Demos, Vasileios; Magriotis, Plato Α.
Source:
Tetrahedron letters 2020 v.61 no.40 pp. 152375
ISSN:
0040-4039
Subject:
beta-lactams,   etc   ; chemical reactions; chemical structure; diastereoselectivity; imines;     Show all 5 Subjects
Abstract:
... A highly efficient Gilman-Speeter synthesis of 3,4-trisubstituted β-lactams possessing a 4-aryl substituent is described, employing a direct, uncatalyzed Mannich reaction between TMS imines and TMS ketene acetals. The process avoids cryogenic conditions, making it more amenable to process-scale use than related methods for β-lactam synthesis. A Gilman-Speeter diastereoselective version using a sul ...
DOI:
10.1016/j.tetlet.2020.152375

3. Concise Synthesis and Antimicrobial Evaluation of the Guanidinium Alkaloid Batzelladine D: Development of a Stereodivergent Strategy

Author:
Lin, You-Chen; Ribaucourt, Aubert; Moazami, Yasamin; Pierce, Joshua G.
Source:
Journal of the American Chemical Society 2020 v.142 no.21 pp. 9850-9857
ISSN:
1520-5126
Subject:
beta-lactams,   etc   ; alkaloids; antimicrobial properties; guanidinium; stereochemistry; stereoisomers; stereoselective synthesis;     Show all 7 Subjects
Abstract:
... Herein, we describe a stereodivergent route to (±)-batzelladine D (2), (+)-batzelladine D (2), (−)-batzelladine D (2), and a series of stereochemical analogues and explore their antimicrobial activity for the first time. The concise synthetic approach enables access to the natural products in a sequence of 8–12 steps from readily available building blocks. Highlights of the synthetic strategy incl ...
DOI:
10.1021/jacs.0c04091

4. Palladium-catalyzed four-component carbonylation of allenes, alcohols and nitroarenes

Author:
Geng, Hui-Qing; Hou, Chen-Yang; Wang, Le-Cheng; Peng, Jin-Bao; Wu, Xiao-Feng
Source:
Journal of catalysis 2020 v.381 pp. 271-274
ISSN:
0021-9517
Subject:
beta-lactams,   etc   ; alcohols; catalytic activity; molybdenum; nitroaromatic compounds; oxidants; palladium;     Show all 7 Subjects
Abstract:
... In this communication, a highly selective palladium-catalyzed carbonylative four components procedure for the transformation of allenes, alcohols and nitroarenes has been developed. The desired 2-aminomethyl substituted 3-arylacrylates were produced in good yields with Mo(CO)₆ as the solid CO source. Furthermore, nitroarenes have been used as reaction partners and oxidant in this catalytic system. ...
DOI:
10.1016/j.jcat.2019.11.009

5. Impurity Profiling of a Novel β-Lactam Enhancer: Zidebactam

Author:
Rane, Vipul P.; Ahirrao, Vinod K.; Patil, Kiran R.; Jadhav, Rajiv A.; Yeole, Ravindra D.
Source:
Chromatographia 2020 v.83 no.3 pp. 423-437
ISSN:
0009-5893
Subject:
beta-lactam antibiotics; beta-lactams,   etc   ; acetonitrile; ammonium; antibacterial properties; clinical trials; drugs; formates; hydrophilicity; liquid chromatography; phosphates; quality control; solvents; spectrometers; tandem mass spectrometry; thermal stress;     Show all 16 Subjects
Abstract:
... Zidebactam (ZID) is a novel drug in clinical development; it potentiates the antibacterial activity of β-lactam antibiotics. Two reversed phase liquid chromatographic (RP-LC) methods were developed for ZID; a mass spectrometer (MS) compatible method for identification and another UV detection method for the quantification of impurities. Four impurities and three degradation products (DPs) were ide ...
DOI:
10.1007/s10337-019-03845-3

6. β-lactam antibiotic versus combined β-lactam antibiotics and single daily dosing regimens of aminoglycosides for treating serious infections: A meta-analysis

Author:
Heffernan, Aaron James; Sime, Fekade Bruck; Sun, Jing; Lipman, Jeffrey; Kumar, Anand; Andrews, Katherine; Ellwood, David; Grimwood, Keith; Roberts, Jason
Source:
International journal of antimicrobial agents 2020 v.55 no.3 pp. 105839
ISSN:
0924-8579
Subject:
beta-lactam antibiotics; beta-lactams,   etc   ; aminoglycosides; cohort studies; endocarditis; meta-analysis; mortality; nephrotoxicity; neutropenia; patients; randomized clinical trials; risk; systematic review; therapeutics;     Show all 14 Subjects
Abstract:
... Combining aminoglycosides with β-lactam antibiotics for treating serious infections has not been associated with reduced mortality in previous meta-analyses. However, the multiple daily aminoglycoside dosing regimen principally used in most of the included studies is inconsistent with current practice.To determine if a combination of an aminoglycoside administered as a single daily dose and a β-la ...
DOI:
10.1016/j.ijantimicag.2019.10.020

7. Reciprocal antibiotic collateral sensitivity in Burkholderia multivorans

Author:
Kavanaugh, Logan G.; Flanagan, J. Nicole; Steck, Todd R.
Source:
International journal of antimicrobial agents 2020 v.56 no.1 pp. 105994
ISSN:
0924-8579
Subject:
beta-lactam antibiotics,   etc   ; Burkholderia multivorans; bacteria; chronic diseases; cross resistance; drugs; genes; mutation; sequence analysis;     Show all 9 Subjects
Abstract:
... Antibiotic collateral sensitivity (CS) occurs when a bacterium that acquires resistance to a treatment drug exhibits decreased resistance to a different drug. Here we identify reciprocal CS networks and candidate genes in Burkholderia multivorans. Burkholderia multivorans was evolved to become resistant to each of six antibiotics. The antibiogram of the evolved strain was compared with the immedia ...
DOI:
10.1016/j.ijantimicag.2020.105994

8. Occurrence and distribution of antibiotic resistance genes in sediments in a semi-enclosed continental shelf sea

Author:
Zhang, Yuxuan; Lu, Jian; Wu, Jun; Wang, Jianhua; Lin, Yichen
Source:
The Science of the total environment 2020 v.720 pp. 137712
ISSN:
0048-9697
Subject:
beta-lactams,   etc   ; antibiotic resistance genes; bacteria; bacterial communities; coasts; continental shelf; principal component analysis; sediments;     Show all 8 Subjects
Abstract:
... Extensive and improper overuse of antibiotics resulted in the prevalence of antibiotic resistance genes (ARGs). As the typical semi-enclosed continental shelf sea, the Bohai Sea has been considered as one of the most polluted marine areas in China. However, no comprehensive investigation on the spatial distribution of ARGs in sediments from the Bohai Sea has been reported. A large-scale sampling w ...
DOI:
10.1016/j.scitotenv.2020.137712

9. Binding and Transport of Carboxylated Drugs by the Multidrug Transporter AcrB

Author:
Tam, Heng-Keat; Malviya, Viveka N.; Foong, Wuen-Ee; Herrmann, Andrea; Malloci, Giuliano; Ruggerone, Paolo; Vargiu, Attilio V.; Pos, Klaas M.
Source:
Journal of molecular biology 2020 v.432 no.4 pp. 861-877
ISSN:
0022-2836
Subject:
beta-lactams,   etc   ; Escherichia coli; binding sites; carboxylation; hydrophobicity; molecular models; toxic substances;     Show all 7 Subjects
Abstract:
... AcrAB(Z)-TolC is the main drug efflux transporter complex in Escherichia coli. The extrusion of various toxic compounds depends on several drug binding sites within the trimeric AcrB transporter. Membrane-localized carboxylated substrates, such as fusidic acid and hydrophobic β-lactams, access the pump via a groove between the transmembrane helices TM1 and TM2. In this article, the transport route ...
DOI:
10.1016/j.jmb.2019.12.025
PubMed:
31881208
PubMed Central:
PMC7071731

10. Identification of Monomethyl Sulfate and Sulfate Impurities in Zidebactam Using LC–MS and Application of Mixed-Mode Liquid Chromatography with Charged Aerosol Detection and Ion Chromatography for Quantification

Author:
Ahirrao, Vinod K.; Rane, Vipul P.; Patil, Kiran R.; Jadhav, Rajiv A.; Bhamare, Vijay S.; Yadav, Dharamvir S.; Yeole, Ravindra D.
Source:
Chromatographia 2020 v.83 no.2 pp. 219-228
ISSN:
0009-5893
Subject:
beta-lactams,   etc   ; Gram-negative bacteria; aerosols; clinical trials; drugs; ion exchange chromatography; mass spectrometry; pyridines; sulfates;     Show all 9 Subjects
Abstract:
... Zidebactam (ZID), a novel β-lactam enhancer drug being developed to treat infections caused by Gram-negative bacteria, currently is in phase III clinical development. Two ionic impurities observed in liquid chromatography with charged aerosol detector (CAD) analysis were identified through liquid-chromatography mass spectrometry (LC–MS) as sulfate (SO₄⁻²) and monomethyl sulfate (CH₃OSO₃⁻¹, MMS). T ...
DOI:
10.1007/s10337-019-03836-4

11. Biodegradation of antibiotics: The new resistance determinants – part II

Author:
Reis, Ana C.; Kolvenbach, Boris A.; Nunes, Olga C.; Corvini, Philippe F.X.
Source:
New biotechnology 2020 v.54 pp. 13-27
ISSN:
1871-6784
Subject:
beta-lactams,   etc   ; antibiotic residues; antibiotic resistance; antibiotics; biodegradation; ionophores; macrolides; microbial communities; quinolones;     Show all 9 Subjects
Abstract:
... Antibiotic residues are widespread in the environment and their presence is known to contribute to the propagation of antibiotic resistance. Nevertheless, knowledge on processes involved in their degradation is scattered. This second part of a two part review aims at compiling knowledge on the (bio-) degradation of antibiotics, focusing on β-lactams, macrolides, quinolones and ionophores, as well ...
DOI:
10.1016/j.nbt.2019.08.003

12. Survival benefit associated with clarithromycin in severe community-acquired pneumonia: A matched comparator study

Author:
Kyriazopoulou, Evdoxia; Sinapidis, Dimitrios; Halvatzis, Stamatios; Velissaris, Dimitrios; Alexiou, Nikolaos; Kosmas, Vasilios; Adami, Maria-Evangelia; Kyprianou, Miltiades; Kyprianou, Aikaterini; Stefos, Aggelos; Lada, Malvina; Koutoukas, Pantelis; Pavlaki, Maria; Kyriakoudi, Anna; Makina, Anna; Gogos, Charalambos; Niederman, Michael S.; Giamarellos-Bourboulis, Evangelos J.
Source:
International journal of antimicrobial agents 2020 v.55 no.1 pp. 105836
ISSN:
0924-8579
Subject:
beta-lactams,   etc   ; azithromycin; clarithromycin; fluoroquinolones; patients; pneumonia; regression analysis; retrospective studies; survival rate;     Show all 9 Subjects
Abstract:
... Although analysis of retrospective studies has documented survival benefit from the addition of a macrolide to the treatment regimen for community-acquired pneumonia (CAP), no data are available to determine if there is differential efficacy between members of the macrolide family. In order to investigate this, an analysis was undertaken of data from 1174 patients with CAP who met the new Sepsis-3 ...
DOI:
10.1016/j.ijantimicag.2019.10.017

13. Simultaneous determination of multiclass antibiotics in sewage sludge based on QuEChERS extraction and liquid chromatography-tandem mass spectrometry

Author:
Ajibola, Akinranti S.; Tisler, Selina; Zwiener, Christian
Source:
Analytical methods 2020 v.12 no.4 pp. 576-586
ISSN:
1759-9679
Subject:
beta-lactam antibiotics; beta-lactams,   etc   ; antibiotic residues; ciprofloxacin; detection limit; electrospray ionization mass spectrometry; liquid chromatography; macrolides; oxytetracycline; salts; sewage sludge; solid phase extraction; solvents; sorbents; spectrometers; sulfonamides; tandem mass spectrometry; thiamphenicol; trimethoprim; wastewater treatment; Nigeria;     Show all 21 Subjects
Abstract:
... A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) based methodology with a dispersive solid-phase extraction (d-SPE) clean-up followed by liquid chromatography-triple quadrupole mass spectrometry analysis was developed and validated for simultaneous determination of seventeen multiclass antibiotics in sewage sludge. The target antibiotics included four sulfonamides, three fluoro ...
DOI:
10.1039/c9ay02188d

14. A review of bioanalytical methods for the therapeutic drug monitoring of β-lactam antibiotics in critically ill patients: Evaluation of the approaches used to develop and validate quality attributes

Author:
Caro, Y.S.; Cámara, M.S.; De Zan, M.M.
Source:
Talanta 2020 v.210 pp. 120619
ISSN:
0039-9140
Subject:
beta-lactam antibiotics,   etc   ; calibration; detectors; drug resistance; drugs; guidelines; hospitals; liquid chromatography; monitoring; patients; pharmacokinetics; precision medicine; sepsis (infection);     Show all 13 Subjects
Abstract:
... Due to their broad spectrum of activity and wide therapeutic index, β-lactam antibiotics (β-LA) are commonly used to treat severe sepsis in critically ill patients in intensive care units. This group of patients experiences important physiological changes that alter their pharmacokinetics, and thus, therapeutic drug monitoring (TDM) of β-LA is increasingly used to improve personalized medicine by ...
DOI:
10.1016/j.talanta.2019.120619

15. Optimized aqueous Kinugasa reactions for bioorthogonal chemistry applications

Author:
Bilodeau, Didier A.; Margison, Kaitlyn D.; Ahmed, Noreen; Strmiskova, Miroslava; Sherratt, Allison R.; Pezacki, John Paul
Source:
Chemical communications 2020 v.56 no.13 pp. 1988-1991
ISSN:
1364-548X
Subject:
beta-lactams,   etc   ; alkynes; biocompatible materials; catalytic activity; copper; cycloaddition reactions; lipids; membrane proteins; micelles; models; peptides; surfactants;     Show all 12 Subjects
Abstract:
... Kinugasa reactions hold potential for bioorthogonal chemistry in that the reagents can be biocompatible. Unlike other bioorthogonal reaction products, β-lactams are potentially reactive, which can be useful for synthesizing new biomaterials. A limiting factor for applications consists of slow reaction rates. Herein, we report an optimized aqueous copper(i)-catalyzed alkyne–nitrone cycloaddition in ...
DOI:
10.1039/c9cc09473c

16. α-Acyl-α-diazoacetates in Transition-Metal-Free β-Lactam Synthesis

Author:
Synofzik, Judith; Dar’in, Dmitry; Novikov, Mikhail S.; Kantin, Grigory; Bakulina, Olga; Krasavin, Mikhail
Source:
Journal of organic chemistry 2019 v.84 no.18 pp. 12101-12110
ISSN:
1520-6904
Subject:
beta-lactams,   etc   ; catalytic activity; chemical reactions; chemical structure; diastereoselectivity; imines;     Show all 6 Subjects
Abstract:
... Thermally promoted reaction of α-acyl-α-diazoacetates with imines has been investigated. The transformation, earlier reported predominantly under transition metal catalyzed conditions, delivers α-alkoxycarbonyl-substituted β-lactams with outstanding diastereoselectivity. DFT calculations performed in order to evaluate energetically feasible reaction pathways revealed the intermediacy of 1,3-oxazin ...
DOI:
10.1021/acs.joc.9b02030

17. Artificial intelligence designed drug synthesis: One-pot preparation of trans β-lactams and application to cholesterol absorption inhibitor SCH 47949 synthesis

Author:
Takabatake, Tetsuhiko; Yoneda, Takumi; Otsuka, Jyo; Kagawa, Natsuko; Toyota, Masahiro
Source:
Tetrahedron letters 2019 pp. 150942
ISSN:
0040-4039
Subject:
beta-lactams,   etc   ; absorption; artificial intelligence; arylation; cholesterol; drugs; moieties; stereoselectivity;     Show all 8 Subjects
Abstract:
... An artificial intelligence designed SCH 47949 synthesis is achieved in a stereoselective manner. The key step contains a stereoselective one-pot construction of the trans β-lactam framework via thermal electrocyclization. N-arylation of the β-lactam ring system and a series of functional group transformations synthesized SCH 47949 in a reasonable chemical yield. ...
DOI:
10.1016/j.tetlet.2019.07.033

18. Natural product derivatization with β-lactones, β-lactams and epoxides toward ‘infinite’ binders

Author:
Jouanneau, Morgan; Vellalath, Sreekumar; Kang, Guowei; Romo, Daniel
Source:
Tetrahedron 2019 v.75 no.24 pp. 3348-3354
ISSN:
0040-4020
Subject:
beta-lactams,   etc   ; alcohols; chemical bonding; chemical structure; derivatization; epoxides; therapeutics;     Show all 7 Subjects
Abstract:
... β-Lactones, β-lactams and epoxides are privileged structural motifs found in both therapeutics and natural products. Herein we report several strategies for annulation of these motifs onto natural products that are not known to covalently modify their cellular targets. These strategies can facilitate identification of previously unidentified cellular targets or identify novel cellular targets of t ...
DOI:
10.1016/j.tet.2019.04.068

19. Synthesis of Exclusively 4-Substituted β-Lactams through the Kinugasa Reaction Utilizing Calcium Carbide

Author:
Hosseini, Abolfazl; Schreiner, Peter R.
Source:
Organic letters 2019 v.21 no.10 pp. 3746-3749
ISSN:
1523-7052
Subject:
beta-lactams,   etc   ; calcium carbide; chemical reactions; chemical structure; synthesis;     Show all 5 Subjects
Abstract:
... A new Kinugasa reaction protocol has been elaborated for the one-pot synthesis of 4-substituted β-lactams utilizing calcium carbide and nitrone derivatives. Calcium carbide is thereby activated by TBAF·3H₂O in the presence of CuCl/NMI. The ease of synthesis and use of inexpensive chemicals provides rapid access of practical quantities of β-lactams exclusively substituted at position 4. ...
DOI:
10.1021/acs.orglett.9b01192

20. Evaluation of benzthiazolidine-based formamidinium salts for the synthesis of penem-type β-lactams by uncatalysed carbonylation of acyclic diaminocarbenes

Author:
Jonek, Markus; Buhl, Hannes; Leibold, Michael; Bruhn, Clemens; Siemeling, Ulrich
Source:
Zeitschrift für Naturforschung 2019 v.74 no.4 pp. 365-372
ISSN:
1865-7117
Subject:
beta-lactams,   etc   ; X-ray diffraction; deprotonation; isomers; selenium;     Show all 5 Subjects
Abstract:
... The reaction of [iPr₂N=CHCl]Cl with 2-phenylbenzthiazolidine (Ph-BtzH) and subsequent anion metathesis afforded the formamidinium salt [(Ph-Btz)CH(NiPr₂)][PF₆] ([1aH][PF₆]). The reaction of [1aH][PF₆] with (Me₃Si)₂NNa in the presence of grey selenium furnished the selenourea derivative 1aSe as trapping product of the acyclic diaminocarbene 1a. In the absence of selenium, a 2H-1,4-benzothiazine der ...
DOI:
10.1515/znb-2019-0017