Andreas Bender, Assistant Professor for Medicinal Chemistry in the Medicinal Chemistry Division of the Leiden / Amsterdam Center for Drug Research, received the

Viral diseases constitute one of the major challenges in modern medicine. Membrane-targeting have broad-spectrum potential and could distinguish viral membranes from the host cell plasma membrane by the difference in membrane curvature.

This thesis describes the development of a variety of mannosylated conjugates. Antigen presenting cells bear mannoside recognizing receptors that actively transport antigen into the cell. This thesis exploits this feature for the development of improved vaccines.

The adsorption of D2 and CO2 on catalyst surfaces is studied using a molecular beam in ultra-high vacuum.

The main goal of the research described in this thesis was the development of new photoactivated chemotherapy (PACT) ruthenium(II) complexes bearing a non-toxic photolabile ligand.

Promotor: M. Ubbink, Co-Promotor: R. T. Dame

Design and synthesis of two 3-substituted swainsonine derivatives with the aim to improve the potency and selectivity towards Golgi alpha-mannosidase II.

Synthetic methodlogy is described, aiding in the synthetic preparation of putative inhibitors of retaining and inverting glycosidases and glycosyl transferases. All constructs are cyclophellitol-based cyclitols.

The chemical synthesis of inhibitors and probes targeting endo-glycosidases.

Theorists have recently made substantial progress in simulating reactive molecule-metal surface scattering but still face major challenges. The grand challenge is to develop an approach that enables accurate predictive calculations of reactions involving electronically excited states with potential…

The probability for dissociation of molecules on metal surfaces, which often controls the rate of industrially important catalytic processes, can depend strongly on how energy is partitioned in the incident molecule. There are many example systems where the addition of vibrational energy promotes reaction…

Promotor: E. Bouwman Co-Promotor: S. Bonnet

An accurate description of reactive scattering of molecules on metal surfaces often requires the modeling of energy transfer between the molecule and the surface phonons. Although ab initio molecular dynamics (AIMD) can describe this energy transfer, AIMD is at present untractable for reactions with…

Photocatalysis has emerged as a powerful tool for enabling challenging transformations in organic synthesis. This thesis explores the development of several photocatalytic reactions designed to form carbon-heteroatom bonds from less-functionalized precursors.

Former Chemistry PhD student Tiddo Mooibroek is one of the 25 nominees for the title New Scientist Science Talent 2017. Nobel prize winner Ben Feringa will announce the winner at the New Scientist Live: Nobelprijs event on June 22, after a rating of the candidates by a jury and a public vote.

A common assumption in chemistry is that the coordination number of a catalyst's surface determines the reactivity of the reaction it catalyses. Strikingly, Leiden chemists have now proven that this is not true for nature’s most simple chemical reaction: the dissociation of hydrogen. The researchers…

This thesis describes the use of an activity-based proteomics method to study the endocannabinoid system.

How do classroom demonstration experiments help students learn chemical reasoning? Marie-Jetta den Otter, PhD student at ICLON, researched this. She defends her thesis on 6 December.

Promotors: Prof.dr. E. Bouwman, Prof.dr. E. Drent

The dissociative chemisorption of methane on metal surfaces is of fundamental and practical interest, being a rate-limiting step in the steam reforming process. The reaction is best modeled with quantum dynamics calculations, but these are currently not guaranteed to produce accurate results because…

This thesis has shed light on some of the ways in which the local electrolyte composition can differ from the bulk and how these changes in the local reaction environment can determine the activity and/or selectivity of two important electrocatalytic reactions, namely, electrochemical CO2 reduction…

Quantum hardware comes with a different computing paradigm and new ways to tackle applications. Much effort has to be put into understanding how to leverage this technology to give real-world advantages in areas of interest for industries such as combinatorial optimization or machine learning.

Several techniques are explored for going beyond the born-oppenheimer static surface model for molecule-surface reactions.

Promotor: M. Ubbink, Co-promotor: G. Siegal

Sphingolipids are important membrane compounds with a variety of functions. In mammalian cells, different enzymes are involved in the metabolism of sphingolipids, but interruption of this metabolism process leads to different diseases.

Nicotinamide adenine dinucleotide (NAD+) is the substrate used for the introduction of the ubiquitous and highly dynamic PTM in which either one or multiple adenosine diphosphate ribose (ADPr) moieties are covalently attached to a nucleophilic side chain of an specific amino acid in the target protein…

Neuraminidases are enzymes that cleave glycosidic linkages of sialic acid. These enzymes are involved in influenza infections as well as in many cellular processes in mammals and micro-organisms.

In the search for new medicines against diseases such as cancer, a Leiden team has developed a new workflow. This approach combines artificial intelligence (AI) with molecular modelling and is suitable for finding unknown and innovative drug structures, the researchers proved.

In this thesis we have discussed several parameters that affect the electrochemical conversion of enviromentaly harmful molecules such as nitrates and carbon dioxide to more valuable and less deleterious compounds, in order to cast light onto the mechanism of the reaction to achieve an efficient and…

Promotores: H.S. Overkleeft, G.A. van der Marel, Co-Promotor: J.D.C. Codee

The main goal of this thesis is to achieve advanced control of binding properties in bis-pyrrolic and macrocyclic pyrrolic receptors by light.

Promotor: M.T.M. Koper, Co-Promotor: F. Calle-Vallejo

Promotor: G.A. van der Marel, Co-Promotor: J.D.C. Codée

The goal of this thesis is to understand how interfacial parameters, such as the addition of organic additives, bulk pH or metal cations of the electrolyte, affect the relevant electrocatalytic reactions, i.e. electrochemical CO2 reduction reaction or hydrogen evolution reaction.

Fundamental understanding of molecular reactions on metal surfaces is important for improving heterogeneous catalysis.

Methods for accurately computing the interaction of molecules with metal surfaces are critical to understanding and thereby improving heterogeneous catalysis.

Dit proefschrift beschrijft een collectie aan alternatieve strategieën voor het begrijpen, ontwerpen en toepassen van lipide nanosystemen, waarin de rol van de bio-nano interacties centraal staan. In het bijzonder wordt gekeken naar de interactie van RNA-lipide nanosystemen, bekend van de toepassing…

The work in this thesis has been focused on two subjects. The first is the assembly of alginate oligosaccharides and the generation of building blocks for the enzymatic synthesis of alginate, and the second is the total synthesis of large fragments of the zwitterionic SP1 polysaccharide.

Carbohydrates are present on the surface of bacteria making them suitable antigen candidates for vaccine development. This thesis deals with the synthesis of two carbohydrate-based components; the capsular polisaccharide of S. aureus type 5 and teichoic acids from staphilococci and enterococci speci…

The primary goal of this research is to deepen our understanding of substrate-enzyme interactions in Glycoside hydrolases. For this purpose, Bacillus circulans xylanase (BcX) has been selected as a well-established model to examine the Michaelis complex and glycosyl-enzyme adduct.

Molecular complexes can be used as electrocatalysts for oxygen reduction, water oxidation, and/or hydrogen peroxide production.

Promotor: G. J. Kroes

This thesis investigates the relations between metabolism and anatomy through the use of Magnetic Resonance Imaging (MRI).

This thesis describes the design, synthesis, and immunological evaluation of varying (neo)antigenic peptide conjugates containing either a TLR2 or a TLR7 agonist.

Nonadiabatic energy transfer from the translational motion (T) of a molecule impinging on metal surface to the metal’s electrons may determine whether the molecule can lose enough energy to adsorb or react.

This thesis focused on the exploration of monolayer graphene as a membrane in direct methanol fuel cell (DMFC) applications, with improvements achieved through plasma exposure or damage- free chemical functionalization.

This thesis comprises the development of reproducible synthesis procedures for two-dimensional materials (composed of boron, nitrogen and carbon) on different metallic surfaces.