Automated medicinal chemistry

BAY-069, a Novel (Trifluoromethyl)pyrimidinedione-Based BCAT1/2 Inhibitor and Chemical Probe

The branched-chain amino acid transaminases (BCATs) are enzymes that catalyze the first reaction of catabolism of the essential branched-chain amino acids to branched-chain keto acids to form glutamate. They are known to play a key role in different cancer types. Here, we report a new structural class of BCAT1/2 inhibitors, (trifluoromethyl)pyrimidinediones, identified by a high-throughput screening campaign and subsequent optimization guided by a series of X-ray crystal structures. Our potent dual BCAT1/2 inhibitor BAY-069 displays high cellular activity and very good selectivity. Along with a negative control (BAY-771), BAY-069 was donated as a chemical probe to the Structural Genomics Consortium.

Evolution of Molecularly Imprinted Enzyme Inhibitors: From Simple Activity Inhibition to Pathological Cell Regulation

Molecular imprinting represents one of the most promising strategies to design artificial enzyme inhibitors. However, the study of molecularly imprinted enzyme inhibitors (MIEIs) remains at a primary stage. Advanced applications of MIEIs for cell regulation have rarely been explored. Using a solid-phase oriented imprinting strategy so as to leave the active site of the enzymes accessible, we synthesized two MIEIs that exhibit high specificity and potent inhibitory effects (inhibition constant at low nM range) towards trypsin and angiogenin. The trypsin MIEI inhibits trypsin activity, tryptic digestion-induced extracellular matrix lysis and cell membrane destruction, indicating its utility in the treatment of active trypsin-dependent cell injury. The angiogenin MIEI blocks cancer cell proliferation by suppressing the ribonuclease activity of angiogenin and decreasing the angiogenin level inside and outside HeLa cells. Our work demonstrates the versatility of MIEIs for both enzyme inhibition and cell fate manipulation, showing their great potential as therapeutic drugs in biomedicine.

Automation of Synthesis in Medicinal Chemistry: Progress and Challenges

Since the 1990s, concerted attempts have been made to improve the efficiency of medicinal chemistry synthesis tasks using automation. Although impacts have been seen in some tasks, such as small array synthesis and reaction optimization, many synthesis tasks in medicinal chemistry are still manual. As it has been shown that synthesis technology has a large effect on the properties of the compounds being tested, this review looks at recent research in automation relevant to synthesis in medicinal chemistry. A common theme has been the integration of tasks, as well as the use of increased computing power to access complex automation platforms remotely and to improve synthesis planning software. However, there has been more limited progress in modular tools for the medicinal chemist with a focus on autonomy rather than automation.

Natural Products for Drug Discovery in the 21st Century: Innovations for Novel Drug Discovery

The therapeutic properties of plants have been recognised since time immemorial. Many pathological conditions have been treated using plant-derived medicines. These medicines are used as concoctions or concentrated plant extracts without isolation of active compounds. Modern medicine however, requires the isolation and purification of one or two active compounds. There are however a lot of global health challenges with diseases such as cancer, degenerative diseases, HIV/AIDS and diabetes, of which modern medicine is struggling to provide cures. Many times the isolation of "active compound" has made the compound ineffective. Drug discovery is a multidimensional problem requiring several parameters of both natural and synthetic compounds such as safety, pharmacokinetics and efficacy to be evaluated during drug candidate selection. The advent of latest technologies that enhance drug design hypotheses such as Artificial Intelligence, the use of 'organ-on chip' and microfluidics technologies, means that automation has become part of drug discovery. This has resulted in increased speed in drug discovery and evaluation of the safety, pharmacokinetics and efficacy of candidate compounds whilst allowing novel ways of drug design and synthesis based on natural compounds. Recent advances in analytical and computational techniques have opened new avenues to process complex natural products and to use their structures to derive new and innovative drugs. Indeed, we are in the era of computational molecular design, as applied to natural products. Predictive computational softwares have contributed to the discovery of molecular targets of natural products and their derivatives. In future the use of quantum computing, computational softwares and databases in modelling molecular interactions and predicting features and parameters needed for drug development, such as pharmacokinetic and pharmacodynamics, will result in few false positive leads in drug development. This review discusses plant-based natural product drug discovery and how innovative technologies play a role in next-generation drug discovery.

Automating drug discovery

Small-molecule drug discovery can be viewed as a challenging multidimensional problem in which various characteristics of compounds - including efficacy, pharmacokinetics and safety - need to be optimized in parallel to provide drug candidates. Recent advances in areas such as microfluidics-assisted chemical synthesis and biological testing, as well as artificial intelligence systems that improve a design hypothesis through feedback analysis, are now providing a basis for the introduction of greater automation into aspects of this process. This could potentially accelerate time frames for compound discovery and optimization and enable more effective searches of chemical space. However, such approaches also raise considerable conceptual, technical and organizational challenges, as well as scepticism about the current hype around them. This article aims to identify the approaches and technologies that could be implemented robustly by medicinal chemists in the near future and to critically analyse the opportunities and challenges for their more widespread application.

Automated synthesis of a library of triazolated 1,2,5-thiadiazepane 1,1-dioxides via a double aza-Michael strategy

The construction of a 96-member library of triazolated 1,2,5-thiadiazepane 1,1-dioxides was performed on a Chemspeed Accelerator (SLT-100) automated parallel synthesis platform, culminating in the successful preparation of 94 out of 96 possible products. The key step, a one-pot, sequential elimination, double-aza-Michael reaction, and [3 + 2] Huisgen cycloaddition pathway has been automated and utilized in the production of two sets of triazolated sultam products.

Drug discovery chemistry: a primer for the non-specialist

Like all scientific disciplines, drug discovery chemistry is rife with terminology and methodology that can seem intractable to those outside the sphere of synthetic chemistry. Derived from a successful in-house workshop, this Foundation Review aims to demystify some of this inherent terminology, providing the non-specialist with a general insight into the nomenclature, terminology and workflow of medicinal chemists within the pharmaceutical industry.

Maximizing efficiency in the production of compound libraries

Efficiency is one of the most important criteria in departments responsible for the production of compounds in a library format. Consequently, this was a key factor in the initial design of our automated medicinal chemistry department, established some years ago. Nonetheless, we were able to improve and optimize our workflows and processes constantly. Here, we outline our current setup, from design to submission of libraries, and discuss which procedures and techniques appear to be useful for us and which ones turned out to be less effective. The aim of the manuscript is not to present individualized and tailor-made solutions in our laboratory but rather to describe approaches (often executed with commercial equipment) which might be of relevance for a broader readership working in this field.

Automated Liquid−Liquid Extraction Workstation for Library Synthesis and Its Use in the Parallel and Chromatography-Free Synthesis of 2-Alkyl-3-alkyl-4-(3H)-quinazolinones

An automated liquid-liquid extraction workstation has been developed. This module processes up to 96 samples in an automated and parallel mode avoiding the time-consuming and intensive sample manipulation during the workup process. To validate the workstation, a highly automated and chromatography-free synthesis of differentially substituted quinazolin-4(3H)-ones with two diversity points has been carried out using isatoic anhydride as starting material.

Integrated microreaction system for optical resolution of racemic amino acids

We developed a novel microreaction system for optical resolution of racemic amino acids. This device, which is based on a continuous microfluidic system, consists of an enzyme-immobilized microreactor and a microextractor. Use of the enzyme-microreactor, which was prepared by membrane formation on the microchannel surface, enabled a highly enantioselective reaction for a racemic amino acid derivative. The microextractor provided a laminar flow of two immiscible solutions, which enabled selective extraction of the product. Using this integrated device, we could perform efficient continuous production of optically pure unnatural amino acids.