Results 41 to 50 of about 612,998 (297)

Trifluoromethylated Heterocycles From Beta-trifluoroacetyl-lactams and Beta-trifluorobenzolactams [PDF]

, 1993
Trifluoromethyl substituted heterocycles have been prepared by condensation of the new beta-trifluoroacetyl-lactams 1 and -benzolactams 2 with methylhydrazine and benzamidine as bis-nucleophiles without opening of the lactam ...
Janousek, Z., Zdenek Janousek, Bouillon, JP., Ates, C., Heinz G. Viehe, Jean-Philippe Bouillon, Viehe, HG., Célâl Ates   +7 more
core   +1 more source

Efficient Synthesis of New Beta-lactams [PDF]

, 1993
The synthesis of beta-lactams was carried out by N-arylpropionamide cyclisation in a mixture of N,N-dimethylformamide and anhydrous sodium carbonate under nitrogen atmosphere with 50 to 90 ...
B. LETOIS, M. ROBBA, D. PERRINE, SATURNINO, Carmela, J. C. LANCELOT   +4 more
core   +1 more source

Profile of Enterobacteria Resistant to Beta-Lactams

Antibiotics, 2020
A serious emerging problem worldwide is increased antimicrobial resistance. Acquisition of coding genes for evasion methods of antimicrobial drug mechanisms characterizes acquired resistance. This phenomenon has been observed in Enterobacteriaceae family.
Andressa Liberal Santos, Adailton Pereira dos Santos, Célia Regina Malveste Ito, Pedro Henrique Pereira de Queiroz, Juliana Afonso de Almeida, Marcos Antonio Batista de Carvalho Júnior, Camila Zanatta de Oliveira, Melissa Ameloti G. Avelino, Isabela Jubé Wastowski, Giselle Pinheiro Lima Aires Gomes, Adenícia Custódia Silva e Souza, Lara Stefânia Netto de Oliveira Leão Vasconcelos, Mônica de Oliveira Santos, Carla Afonso da Silva, Lilian Carla Carneiro   +14 more
doaj   +1 more source

Stereoselective Synthesis of Ezetimibe via Cross-Metathesis of Homoallylalcohols and α‑Methylidene-β-Lactams [PDF]

, 2016
Ru-catalyzed cross-metathesis (CM) reaction between β-arylated α-methylidene-β-lactams and terminal olefins was developed. The CM reaction is effectively catalyzed with Hoveyda–Grubbs second-generation catalyst affording corresponding α-alkylidene-β-aryl-
Filip Hessler (544447), Nikola Topolovčan (2567920), Marek Humpl (2987811), Jan Veselý (1843195), Martin Kotora (544451), Jiří Tauchman (2079664), Jan Kretschmer (2987814), Ivana Císařová (1580947)   +7 more
core   +1 more source

Stress History Establishes a Transient Tolerant State That Shapes Antibiotic Survival Upon Resuscitation

Advanced Science, EarlyView.
High‐throughput single‐cell analysis of resuscitating bacteria reveals a starvation‐history‐dependent transiently tolerant subpopulation that survives β$\beta$‐lactam exposure by temporarily reducing growth. Distinct from classical persisters, these actively growing yet dynamically modulated cells dominate survival across clinically relevant antibiotic
Kieran Abbott, Georgeos Hardo, Ruizhe Li, Jack Bradley, Ashraf Zarkan, Somenath Bakshi   +5 more
wiley   +1 more source

Imide and isatin derivatives as β-lactam mimics of β-lactam antibiotics [PDF]

, 2002
Activated γ-lactams, which are derivatives of succinimide, phthalimide and isatin with suitable elements of molecular recognition, have been synthesised as mimics of the ß-lactam antibiotics and their chemical and biological reactivity ...
Ronald H.B. Galt, Michael I. Page, Hadfield, Peter S., Page, Michael I., Peter S. Hadfield, Bartholomew Vilanova, Lorraine A. Casey, Galt, Ronald H.B., Casey, Lorraine A., Vilanova, Bartholomew, Galt, Ronald H. B.   +10 more
core   +1 more source

Polychip‐A High‐Throughput Droplet Microfluidics Platform for Interrogating Microbial Interactions

Advanced Science, EarlyView.
Polychip, a fully integrated droplet microfluidics platform, enables high‐throughput, single‐cell resolution screening of polymicrobial interactions. By seamlessly combining six automated microfluidics operations on a single chip, the system accelerates antimicrobial discovery by 11 to 14 times compared to traditional robotic methods.
Jeong Jae Han, Adrian Ryan Guzman, Aifen Zhou, Han Zhang, Rohit Gupte, Haemin Jung, Kaylee Delgado, Sini Skariah, Ali Sultan, Arul Jayaraman, Paul de Figueiredo, Arum Han   +11 more
wiley   +1 more source

Structural and Functional Siderophore Remodeling by Enzymatic Delipidation

Angewandte Chemie, EarlyView.
A surprising functional switch in bacterial siderophores was discovered through genome mining and the analysis of environmental and pathogenic Pandoraea species. Pandorachelin B, a lipocyclopeptide that promotes swarming motility, is cleaved by a specialized acylase, yielding a ring‐contracted, homodetic cyclopeptide, pandorachelin A, which exhibits ...
Elena Herzog, Keishi Ishida, Evelyn M. Molloy, Ron Hermenau, Kirstin Scherlach, Christian Hertweck   +5 more
wiley   +2 more sources

A Strong Lewis Acidic Diethylsilylium Catalyst for Direct Sulfonamidation of Challenging Ketones

Advanced Science, EarlyView.
Low‐substitution‐order silylium ions (R2HSi+) exhibit exceptional Lewis acidic activity. We report diethylsilylium‐catalyzed reductive sulfonamidation of functionalized ketones to access β‐amino esters. The in situ generated ion pair shows enhanced reactivity, with diethylsilane serving as both reductant and precatalyst. The developed protocol proceeds
Woo Hee Kim, Muhammad Israr, You Kyoung Chung, Shinwon Ham, Joonsuk Huh, Han Yong Bae   +5 more
wiley   +1 more source

A Novel Class of “Super‐Strained” Spiro Heterocycles: Gateway to 1‐Azaspiro[3.3]heptane Derivatives, and Biological Validation

Angewandte Chemie, EarlyView.
A new class of “super‐strained” spiro heterocycles—spirocyclic 1‐azabicyclo[1.1.0]butanes—was synthesized via insertion of cyclobutane‐, oxetane‐, and azetidine‐containing sulfonium reagents into substituted azirines. The stability of this new class of compounds was studied.
Philipp Natho, Annarita Vicenti, Marco Colella, Francesco Pasca, Giuseppe Romanazzi, Mauro Niso, Carmen Abate, Ernesto Mesto, Emanuela Schingaro, Renzo Luisi   +9 more
wiley   +2 more sources