Highly Diastereoselective Construction of Carbon- Heteroatom Quaternary Stereogenic Centers in the Synthesis of Analogs of Bioactive Compounds: From Monofluorinated Epoxyalkylphosphonates to α-Fluoro-, β-, or γ-Amino Alcohol Derivatives of Alkylphosphonates

The synthesis of the stable surrogates of an important amino acid (R)-4-amino-3-hydroxybutyric acid (GABOB) such as substituted hydroxy aminophosphonic acids bearing a quaternary stereogenic center is presented. Highly diastereoselective formations of fluorinated spiroepoxy alkylphosphonate or related tertiary carbon-containing oxiranes from β-keto phosphonates possessing methyl, phenyl, or cyclohexenyl substituents, are reported. Stereoselective acid-promoted epoxide opening by bromide or azide followed by reduction/protection afforded tertiary bromides or N-Boc derivatives of β-amino-γ-hydroxy alkylphosphonates in most cases, while the reactions of oxiranes with different amines yielded their β-hydroxy-γ-amino regioisomers. Surprisingly, during the synthesis of amino phosphonic acids, we observe that the acid-induced rearrangement proceeded in a high diastereospecific manner, leading finally to substituted β-hydroxy-γ-aminoalkylphosphonic acids.

Copper-catalyzed asymmetric allylic C–H amination of alkenes using N-arylhydroxylamines

The first Cu-catalyzed asymmetric allylic C–H amination of alkenes with N-aryl hydroxylamines has been developed. Metal-complexes isolation, ESI-MS analysis and the DFT calculations provided key insights on mechanistic pathway.

Fluorinated Molecules and Nanotechnology: Future 'Avengers' against the Alzheimer's Disease?

Alzheimer’s disease (AD) is a serious health concern, affecting millions of people globally, which leads to cognitive impairment, dementia, and inevitable death. There is still no medically accepted treatment for AD. Developing therapeutic treatments for AD is an overwhelming challenge in the medicinal field, as the exact mechanics underlying its devastating symptoms is still not completely understood. Rather than the unknown mechanism of the disease, one of the limiting factors in developing new drugs for AD is the blood–brain barrier (BBB). A combination of nanotechnology with fluorinated molecules is proposed as a promising therapeutic treatment to meet the desired pharmacokinetic/physiochemical properties for crossing the BBB passage. This paper reviews the research conducted on fluorine-containing compounds and fluorinated nanoparticles (NPs) that have been designed and tested for the inhibition of amyloid-beta (Aβ) peptide aggregation. Additionally, this study summarizes fluorinated molecules and NPs as promising agents and further future work is encouraged to be effective for the treatment of AD.

Industrial medicinal chemistry insights: neuroscience hit generation at Janssen

The role of medicinal chemistry has changed over the past 10 years. Chemistry had become one step in a process; funneling the output of high-throughput screening (HTS) on to the next stage. The goal to identify the ideal clinical compound remains, but the means to achieve this have changed. Modern medicinal chemistry is responsible for integrating innovation throughout early drug discovery, including new screening paradigms, computational approaches, novel synthetic chemistry, gene-family screening, investigating routes of delivery, and so on. In this Foundation Review, we show how a successful medicinal chemistry team has a broad impact and requires multidisciplinary expertise in these areas.

Application of Free Energy Perturbation for the Design of BACE1 Inhibitors

Novel spiroaminodihydropyrroles probing for optimized interactions at the P3 pocket of β-secretase 1 (BACE1) were designed with the use of free energy perturbation (FEP) calculations. The resulting molecules showed pIC50 potencies in enzymatic BACE1 inhibition assays ranging from approximately 5 to 7. Good correlation was observed between the predicted activity from the FEP calculations and experimental activity. Simulations run with a default 5 ns approach delivered a mean unsigned error (MUE) between prediction and experiment of 0.58 and 0.91 kcal/mol for retrospective and prospective applications, respectively. With longer simulations of 10 and 20 ns, the MUE was in both cases 0.57 kcal/mol for the retrospective application, and 0.69 and 0.59 kcal/mol for the prospective application. Other considerations that impact the quality of the calculations are discussed. This work provides an example of the value of FEP as a computational tool for drug discovery.

One-Pot Synthesis of N-Substituted β-Amino Alcohols from Aldehydes and Isocyanides

A practical two-stage one-pot synthesis of N-substituted β-amino alcohols using aldehydes and isocyanides as starting materials has been developed. This method features mild reaction conditions, broad scope, and general tolerance of functional groups. Based on a less common central carbon-carbon bond disconnection, this protocol complements traditional approaches that involve amines and various carbon electrophiles (epoxides, α-halo ketones, β-halohydrins). Medicinally relevant products can be prepared in a concise and efficient way from simple building blocks, as demonstrated in the synthesis of the antiasthma drug salbutamol. Upgrading the synthesis to an enantioselective variant is also feasible.