Book of abstracts version 5

Synthesis of Beta-lactam in three steps
Book of abstracts SPOC 2018
Author
Narjiss Ajary
Academy of Technology for Health and Environment
Avans Hogeschool, Breda
Paula Contreras Carballada
Erik Rump
eta-lactam in three steps
Abstract
Beta-lactam molecules are a part of antibiotic families and are commonly used for the treatment o f bacterial infections.
The important part of the molecule is the four membered ring, which gives the molecule its reactive characteristics to
break down cell walls of the bacteria. To prevent the bacteria from becoming resistant to the commonly used Beta-lactam
antibiotics, like Penicillin, different Beta-lactam derivatives are synthesised [1]. In this study, the synthesis is executed in
three steps. The first step being condensation reaction with N-benzylhydroxylamine and Ethyl glyoxylate, which gives a
Nitrone. The Nitrone is then used for the second synthesis, which is a 1,3 Dipolar Cycloaddition, with trimethylsilyl
acetylene. The formed isoxazole is then used for the third synthesis, which is shown in Figure 1. A fluoride source is used
to remove the trimethylsilyl group, which then gives the Beta-lactam product [2]. The goal of this study is to find an
effective fluoride source for the removal of the trimethylsilyl group in the third synthesis. In the original research of …,
TBAF is used, but this contains water which can protonate the intermediate and this doesn’t form the desired product [3]
That’s why sodium fluoride was used. The obtained products were purified with column chromatography and analysed
with H-NMR and FT-IR.
Keywords: Beta-lactam, 1,3 Dipolar cycloaddition, isoxazole, nitrone, fluoride
Table of content
Figure 1: Reaction of the synthesis of the Beta-Lactam molecule.
[1] C. Hubschwerlen (2007). B-lactam Antibiotics. Comprehensive Medicinal Chemistry II. 480-488.
[2] P. DeShong et al. (1994) A New Approach to the Synthesis of Monocyclic B -Lactam Derivatives. J. Org. Chem. 6282-
6286.
[3] P. Contreras Carballada,(2003). Untersuchung zur Darstellung von 5 -trimethylsilyl-substituierten Isoxazolinen und
deren Spaltung zu B-lactamen.
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