Results 271 to 280 of about 764,478 (294)

Diazoketones as precursors in β-lactam synthesis. New insights into the mechanism of the photochemically induced Staudinger reaction

Journal of the Chemical Society, Perkin Transactions 1, 2001
Diazoketones 1–3, derived from suitably protected amino acids (Ala, Val and Tle), have been photochemically rearranged in the presence of imines leading exclusively to trans-arranged 4-aryl- and cinnamoyl-substituted β-lactams 17–33 with up to 84% yield. Selectivities were dependent on the steric demand of the amino acid side-chain ranging from 65 ∶ 35
Michael R. Linder, Wolfgang U. Frey, Joachim Podlech   +2 more
openaire   +1 more source

Synthesis of 4-aminoguaiazulene and its δ-lactam derivatives

Tetrahedron Letters, 2011
Abstract A method for nitrogen insertion into guaiazulene hydrocarbons is developed. A one-pot reaction of 7-isopropyl-1-methylazulene-4-carboxylic acid, diphenylphosphoryl azide, and an alcohol (MeOH, tBuOH or BnOH) affords the corresponding carbamates.
Kiriazis Alexandros, Aumuller Ingo, Yli-Kauhaluoma Jari   +2 more
openaire   +1 more source

Synthesis of spiro-annelated γ-lactams by isocyanide-based multicomponent reactions involving hem-disubstituted bifunctional reagents

Proceedings of The 17th International Electronic Conference on Synthetic Organic Chemistry, 2013
The new bifunctional hem-disubstituted alicyclic compounds IIIa-e and IVa-e were synthesized in several steps involving alkylation with allyl bromide following oxidative cleavage. Hem-disubstitues oxo-esters IIIa-e were introduced into azido-Ugi reaction followed by one-pot intramolucular bond formation to afford 3-(tetrazol-5-yl)-2-azaspiro[4.n]alkan ...
Vasiliy Stolyarenko, Ananatoliy Evdokimov, Vladimir Shishkin   +2 more
openaire   +1 more source

Bacterial production of carbapenems and clavams: evolution of β-lactam antibiotic pathways

Trends in Microbiology, 1998
Research into two of the four classes of naturally produced beta-lactams--the clavams and carbapenems--has started to throw light upon their biochemical pathways and underlying genetics. Interesting similarities between these two classes, from their joint discovery to an apparently common beta-lactam ring-forming enzyme, are now being revealed.
S J, McGowan, B W, Bycroft, G P, Salmond
openaire   +2 more sources

Clinical Evaluation of In Vitro Tests in Diagnosis of Immediate Allergic Reactions to β-Lactam Antibiotics

Allergy & Clinical Immunology International - Journal of the World Allergy Organization, 2002
María Sanz, P.M. Gamboa, A.L. de Weck
openaire   +1 more source

β-lactam antibiotics: An overview from a medicinal chemistry perspective

European Journal of Medicinal Chemistry, 2020
Lidia Moreira Lima, Gisele Barbosa, Eliezer J Barreiro   +2 more
exaly  

Molecular Mechanisms, Epidemiology, and Clinical Importance of β-Lactam Resistance in Enterobacteriaceae

International Journal of Molecular Sciences, 2020
Brunella Posteraro, Maurizio Sanguinetti, Mario Tumbarello   +2 more
exaly  

Mn(III)-Promoted Sulfur-Directed 4-Exo-Trig Radical Cyclization of Enamides to β-Lactams

Tetrahedron, 1998
openaire   +1 more source

The Importance of Porins and β-Lactamase in Outer Membrane Vesicles on the Hydrolysis of β-Lactam Antibiotics

International Journal of Molecular Sciences, 2020
Si Won Kim, Jin Hong Chun, Jaesung Kim
exaly  

Alkene Trifluoromethylation-Initiated Remote α-Azidation of Carbonyl Compounds toward Trifluoromethyl γ-Lactam and Spirobenzofuranone-Lactam

ACS Catalysis, 2015
Jin-Shun Lin, Bin Tan, Xin-Yuan Liu
exaly