Bacterial infections constitute a major global health problem, acutely accentuated by the rapid spread of antibiotic resistant
bacterial strains. The widespread need for bacteria to attach – adhere – to target cells before they can initiate an infection
may be used to advantage by targeting the bacterial adhesion tools such as pili and fimbriae for development of novel anti-bacterial
vaccines and drugs. Type 1 fimbriae are widely expressed by Escherichia coli. and are used by uropathogenic strains to mediate attachment to specific niches in the urinary tract. These fimbriae belong
to a class of fibrillar adhesion organelles assembled through the chaperone/usher pathway, one of the terminal branches of
the general secretion pathway in Gram-negative bacteria. Our understanding of the assembly, structure and function of these
structures has evolved significantly over the last decade. Here, we summarize current understanding of the function and biogenesis
of fibrillar adhesion organelles, and provide some examples of recent progress towards interfering with bacterial adhesion
as a means to prevent infection.
Content Type Book Chapter
DOI 10.1007/128_2008_13
Authors
Stefan D Knight, Uppsala Biomedical Center Swedish University of Agricultural Sciences, Department of Molecular Biology SE-75124 Uppsala Sweden
Abstract The Cassini–Huygens mission, comprising the NASA Saturn Orbiter and the ESA Huygens Probe, arrived at Saturn in late June
2004. The Huygens probe descended under parachute in Titan’s atmosphere on 14 January 2005, [...]
The high degree of organisation in the fluid phase of room-temperature ionic liquids has major consequences on their macroscopic
properties, namely on their behaviour as solvents. This nanoscale self-organisation is the result of an interplay between
two types of interaction in the liquid phase – Coulomb and van der Waals – that eventually leads to the formation of medium-range
structures and the recognition of some ionic liquids as composed of a high-charge density, cohesive network permeated by low-charge
density regions.
In this chapter, the structure of the ionic liquids will be explored and some of their consequences to the properties of ionic
liquids analyzed.
Content Type Book Chapter
DOI 10.1007/128_2009_2
Authors
Margarida F. Costa Gomes, Université Blaise Pascal, Clermont-Ferrand/CNRS Laboratoire Thermodynamique et Interactions Moléculaires Aubière France
J. N. Canongia Lopes, Centro de Quimica Estrutural Instituto Superior Técnico Lisbon Portugal
A. A. H. Padua, Université Blaise Pascal, Clermont-Ferrand/CNRS Laboratoire Thermodynamique et Interactions Moléculaires Aubière France
The reversible reaction of primary or secondary amines with enolizable aldehydes or ketones affords nucleophilic intermediates,
enamines. With chiral amines, catalytic enantioselective reactions via enamine intermediates become possible. In this review,
structure-activity relationships and the scope as well as current limitations of enamine catalysis are discussed.
Content Type Book Chapter
DOI 10.1007/128_2008_21
Authors
Petri M. Pihko, University of Jyväskylä Department of Chemistry 35 FI-40014 JYU Jyväskylä Finland
Inkeri Majander, Helsinki University of Technology Department of Chemistry 6100 FI-02015 TKK Espoo Finland
Anniina Erkkilä, Helsinki University of Technology Department of Chemistry 6100 FI-02015 TKK Espoo Finland
The synthesis, purification and characterization of ionic liquids is reviewed. The major synthetic routes to low melting ionic
salts are described in detail. The intrinsic properties of ionic liquids make purification difficult and therefore a special
emphasis is placed on currently employed purification methodologies. Synthetic methods which are designed to avoid specific
impurities are also discussed. For the same reasons highlighted above characterization of ionic liquids presents unique challenges;
the available methods and some of the issues of their use are also reviewed.
Content Type Book Chapter
DOI 10.1007/128_2008_31
Authors
Bronya Clare, Monash University School of Chemistry Clayton Victoria 3800 Australia
Amal Sirwardana, Monash University School of Chemistry Clayton Victoria 3800 Australia
Douglas R. MacFarlane, Monash University School of Chemistry Clayton Victoria 3800 Australia
The term Lewis acid catalysts generally refers to metal salts like aluminium chloride, titanium chloride and zinc chloride.
Their application in asymmetric catalysis can be achieved by the addition of enantiopure ligands to these salts. However,
not only metal centers can function as Lewis acids. Compounds containing carbenium, silyl or phosphonium cations display Lewis
acid catalytic activity. In addition, hypervalent compounds based on phosphorus and silicon, inherit Lewis acidity. Furthermore,
ionic liquids, organic salts with a melting point below 100 °C, have revealed the ability to catalyze a range of reactions
either in substoichiometric amount or, if used as the reaction medium, in stoichiometric or even larger quantities. The ionic
liquids can often be efficiently recovered. The catalytic activity of the ionic liquid is explained by the Lewis acidic nature
of their cations. This review covers the survey of known classes of metal-free Lewis acids and their application in catalysis.
Content Type Book Chapter
DOI 10.1007/128_2008_17
Authors
Oksana Sereda, Clausthal University of Technology Leibnizstr. 6 38678 Clausthal-Zellerfeld Germany
Sobia Tabassum, Clausthal University of Technology Leibnizstr. 6 38678 Clausthal-Zellerfeld Germany
René Wilhelm, Clausthal University of Technology Leibnizstr. 6 38678 Clausthal-Zellerfeld Germany
Relaxation of strain in small ring molecules is reviewed in terms of two mechanisms – σ-relaxation and π-relaxation. The σ-relaxation
occurs in in-plane interaction of the ring σ bonds. Previously proposed σ-aromaticity and surface delocalization are briefly
discussed. The geminal interaction theory for the σ-relaxation of ring strains is discussed and applied. The geminal interaction
is less antibonding or more bonding with decrease in the bond angle, when the hybrid orbital has low s-character for the ring
bonds or has an s-rich lone pair (lone pair effect). π-Relaxation of unsaturated ring molecules results from the cyclic delocalization
of π electrons through the σ bonds on the saturated ring atoms. The two mechanisms of the σ- and π-relaxation are shown to
be necessary for better understanding of ring strains.
Content Type Book Chapter
DOI 10.1007/128_2008_42
Authors
Yuji Naruse, Gifu University Department of Chemistry, Faculty of Engineering Yanagido Gifu 501-1193 Japan
Satoshi Inagaki, Gifu University Department of Chemistry, Faculty of Engineering Yanagido Gifu 501-1193 Japan
This article provides an overview on the chemistry and structure–activity relationships of macrolide-based microtubule-stabilizing
agents. The primary focus will be on the total synthesis or examples thereof, but a brief summary of the current state of
knowledge on the structure–activity relationships of epothilones, laulimalide, dictyostatin, and peloruside A will also be
given. This macrolide class of compounds, over the last decade, has become the subject of growing interest due to their ability
to inhibit human cancer cell proliferation through a taxol-like mechanism of action.
Content Type Book Chapter
DOI 10.1007/128_2008_9
Authors
B. Pfeiffer, Institute of Pharmaceutical Sciences HCI H405 ETH Zürich, Department of Chemistry and Applied Biosciences Wolfgang-Pauli-Str. 10 CH-8093 Zürich Switzerland
C.N. Kuzniewski, Institute of Pharmaceutical Sciences HCI H405 ETH Zürich, Department of Chemistry and Applied Biosciences Wolfgang-Pauli-Str. 10 CH-8093 Zürich Switzerland
C. Wullschleger, Institute of Pharmaceutical Sciences HCI H405 ETH Zürich, Department of Chemistry and Applied Biosciences Wolfgang-Pauli-Str. 10 CH-8093 Zürich Switzerland
K.-H. Altmann, Institute of Pharmaceutical Sciences HCI H405 ETH Zürich, Department of Chemistry and Applied Biosciences Wolfgang-Pauli-Str. 10 CH-8093 Zürich Switzerland
Ionic liquids have been studied for their special solvent properties in a wide range of processes, including reactions involving
carbohydrates such as cellulose and glucose. Biomass is a widely available and renewable resource that is likely to become
an economically viable source of starting materials for chemical and fuel production, especially with the price of petroleum
set to increase as supplies are diminished. Biopolymers such as cellulose, hemicellulose and lignin may be converted to useful
products, either by direct functionalisation of the polymers or depolymerisation to monomers, followed by microbial or chemical
conversion to useful chemicals. Major barriers to the effective conversion of biomass currently include the high crystallinity
of cellulose, high reactivity of carbohydrates and lignin, insolubility of cellulose in conventional solvents, as well as
heterogeneity in the native lignocellulosic materials and in lignin itself. This combination of factors often results in highly
heterogeneous depolymerisation products, which make efficient separation difficult. Thus the extraction, depolymerisation
and conversion of biopolymers will require novel reaction systems in order to be both economically attractive and environmentally
benign. The solubility of biopolymers in ionic liquids is a major advantage of their use, allowing homogeneous reaction conditions,
and this has stimulated a growing research effort in this field. This review examines current research involving the use of
ionic liquids in biomass reactions, with perspectives on how it relates to green chemistry, economic viability, and conventional
biomass processes.
Content Type Book Chapter
DOI 10.1007/128_2008_35
Authors
Suzie Su Yin Tan, Monash University School of Chemistry Clayton Campus, Wellington Road Clayton VIC 3800 Australia
Douglas R. MacFarlane, Monash University School of Chemistry Clayton Campus, Wellington Road Clayton VIC 3800 Australia
