Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Gerd Kleefeld is active.

Publication


Featured researches published by Gerd Kleefeld.


The Journal of Antibiotics | 2017

5-O-Mycaminosyltylonolide antibacterial derivatives: design, synthesis and bioactivity

Akihiro Sugawara; Hitomi Maruyama; Sho Shibusawa; Hidehito Matsui; Tomoyasu Hirose; Ayumi Tsutsui; Robrecht Froyman; Carolin Ludwig; Johannes Koebberling; Hideaki Hanaki; Gerd Kleefeld; Satoshi Ōmura; Toshiaki Sunazuka

Tylosin is a 16-membered macrolide broad-spectrum antibiotic that has an important role in veterinary medicine, active against Gram-positive and a restricted range of Gram-negative bacteria. We synthesized 15 types of tylosin-related derivatives by chemical modification and evaluated them against mastitis pathogens. Among them, 20-deoxy-20-{N-methyl-N-[1-(3-quinolyl)-1H-1,2,3-triazol-4-yl]methylamino}-5-O-mycaminosyltylonolide 2f and 20-deoxy-20-{N-benzyl-N-[1-(3-quinolyl)-1H-1,2,3-triazol-4-yl]methylamino}-5-O-mycaminosyltylonolide 2k were found to not only expand their antibacterial impact to include Gram-negative bacteria, such as Escherichia coli and Klebsiella pneumoniae, but also to retain or increase antibacterial activity against Gram-positive bacteria, such as Staphylococcus aureus and Streptococcus uberis in comparison with the parent tylosin.


Archive | 1990

Herbicidal 5h-furan-2-one derivatives

Wolfgang Kramer; Gerd Kleefeld; Jürgen Dr. Bachmann; Peter Babczinski; Hans-Joachim Santel; Klaus Lurssen; Robert R. Schmidt


Archive | 1997

Acylated 4-amino- and 4-hydrazinopyrimidines and their use as pesticides

Thomas Bretschneider; Gerd Kleefeld; Konrad Wernthaler; Christoph Erdelen; Klaus Stenzel


Archive | 1990

5H-Furan-2-on-Derivate

Wolfgang Kramer; Gerd Kleefeld; Jürgen Dr. Bachmann; Peter Babczinski; Hans-Joachim Santel; Klaus Lurssen; Robert R. Schmidt


Archive | 1997

Cyclic imines as pesticides

Andrew Plant; Gerd Kleefeld; Thorsten Pötter; Christoph Erdelen; Norbert Mencke; Andreas Turberg; Ulrike Wachendorff-Neumann


Archive | 1990

Pyridine-substituted esters of acrylic acid

Alexander Dr. Klausener; Gerd Kleefeld; Dieter Berg; Stefan Dutzmann; Gerd Hanssler


Archive | 1992

FUNGICIDAL AGENTS BASED ON HETEROCYCLICALLY SUBSTITUTED SULPHONES

Gerd Kleefeld; Hans-Joachim Diehr; Wilhelm Haas; Heinz-Wilhelm Dehne; Wilhelm Brandes


Archive | 1990

Substituted acrylic acid esters

Alexander Dr. Klausener; Gerd Kleefeld; Wilhelm Brandes; Stefan Dutzmann; Gerd Hanssler


Archive | 1990

Fungicidal pyrid-2-yl-amino acetic acid esters

Alexander Klausener; Gerd Kleefeld; Dieter Berg; Stefan Dutzmann; Gerd Hanssler


Archive | 1990

Thiadiazol-substituted acrylic acid esters and new intermediates

Ulrich Heinemann; Gerd Kleefeld; Stefan Dutzmann; Gerd Hanssler

Researchain Logo
Decentralizing Knowledge