Discovery of a Potent Dual Inhibitor of Aromatase and Aldosterone Synthase.

Estrogen deficiency derived from inhibition of estrogen biosynthesis is a typical condition of postmenopausal women and breast cancer (BCs) patients undergoing antihormone therapy. The ensuing increase in aldosterone levels is considered to be the major cause for cardiovascular diseases (CVDs) affecting these patients. Since estrogen biosynthesis is regulated by aromatase (CYP19A1), and aldosterone biosynthesis is modulated by aldosterone synthase (CYP11B2), a dual inhibitor would allow the treatment of BC while reducing the cardiovascular risks typical of these patients. Moreover, this strategy would help overcome some of the disadvantages often observed in single-target or combination therapies. Following an in-depth analysis of a library of synthesized benzylimidazole derivatives, compound X21 was found to be a potent and selective dual inhibitor of aromatase and aldosterone synthase, with IC50 values of 2.3 and 29 nM, respectively. Remarkably, the compound showed high selectivity with respect to 11ß-hydroxylase (CYP11B1), as well as CYP3A4 and CYP1A2. When tested in cells, X21 showed potent antiproliferative activity against BC cell lines, particularly against the ER+ MCF-7 cells (IC50 of 0.26 ± 0.03 µM at 72 h), and a remarkable pro-apoptotic effect. In addition, the compound significantly inhibited mTOR phosphorylation at its IC50 concentration, thereby negatively modulating the PI3K/Akt/mTOR axis, which represents an escape for the dependency from ER signaling in BC cells. The compound was further investigated for cytotoxicity on normal cells and potential cardiotoxicity against hERG and Nav1.5 ion channels, demonstrating a safe biological profile. Overall, these assays demonstrated that the compound is potent and safe, thus constituting an excellent candidate for further evaluation.

Spectroscopic dataset of Hedione's derivatives gathered during process development.

The dataset of spectroscopic analysis performed on starting materials, intermediates, and products relating to the synthesis of Hedione are hereby presented. The data were acquired in Durham university during the period between October 2020 and September 2021 for the development of a preparative method to Dehydrohedione. The latter is a key intermediate for the synthesis of cis-Hedione, an important fragrance ingredient. Proton, Carbon-13, and Fluorine-19 Nuclear magnetic resonance of the compounds were recorded employing a Varian 600 MHz, and a Bruker Avance-400 instrument. The IR spectra were recorded in a Perkin Elmer Spectrum Two UATR Two FT-IR and the accurate mass employing a Waters QtoF premier as mass spectrometer.

Development of 3α,7α-dihydroxy-6α-ethyl-24-nor-5ß-cholan-23-sulfate sodium salt (INT-767): Process optimization, synthesis and characterization of metabolites.

Herein we report our synthetic efforts in supporting the development of the bile alcohol sulfate INT-767, a FXR/TGR5 dual agonist with remarkable therapeutic potential for liver disorders. We describe the process development to a final route for large scale preparation and analogues synthesis. Key sequences include Grignard addition, a one-pot two-step shortening-reduction of the carboxylic side chain, and the final sulfation reaction. The necessity for additional steps such as the protection/deprotection of hydroxyl groups at the steroidal body was also evaluated for step-economy and formation of side-products. Critical bottlenecks such as the side chain degradation have been tackled using flow technology before scaling-up individual steps. The final synthetic route may be successfully employed to produce the amount of INT-767 required to support late-stage clinical development of the compound. Furthermore, potential metabolites have been synthesized, characterized and evaluated for their ability to modulate FXR and TGR5 receptors providing key reference standards for future drug investigations, as well as offering further insights into the structure-activity relationships of this class of compounds.

Protein domain-based prediction of drug/compound-target interactions and experimental validation on LIM kinases.

Predictive approaches such as virtual screening have been used in drug discovery with the objective of reducing developmental time and costs. Current machine learning and network-based approaches have issues related to generalization, usability, or model interpretability, especially due to the complexity of target proteins' structure/function, and bias in system training datasets. Here, we propose a new method "DRUIDom" (DRUg Interacting Domain prediction) to identify bio-interactions between drug candidate compounds and targets by utilizing the domain modularity of proteins, to overcome problems associated with current approaches. DRUIDom is composed of two methodological steps. First, ligands/compounds are statistically mapped to structural domains of their target proteins, with the aim of identifying their interactions. As such, other proteins containing the same mapped domain or domain pair become new candidate targets for the corresponding compounds. Next, a million-scale dataset of small molecule compounds, including those mapped to domains in the previous step, are clustered based on their molecular similarities, and their domain associations are propagated to other compounds within the same clusters. Experimentally verified bioactivity data points, obtained from public databases, are meticulously filtered to construct datasets of active/interacting and inactive/non-interacting drug/compound-target pairs (~2.9M data points), and used as training data for calculating parameters of compound-domain mappings, which led to 27,032 high-confidence associations between 250 domains and 8,165 compounds, and a finalized output of ~5 million new compound-protein interactions. DRUIDom is experimentally validated by syntheses and bioactivity analyses of compounds predicted to target LIM-kinase proteins, which play critical roles in the regulation of cell motility, cell cycle progression, and differentiation through actin filament dynamics. We showed that LIMK-inhibitor-2 and its derivatives significantly block the cancer cell migration through inhibition of LIMK phosphorylation and the downstream protein cofilin. One of the derivative compounds (LIMKi-2d) was identified as a promising candidate due to its action on resistant Mahlavu liver cancer cells. The results demonstrated that DRUIDom can be exploited to identify drug candidate compounds for intended targets and to predict new target proteins based on the defined compound-domain relationships. Datasets, results, and the source code of DRUIDom are fully-available at: https://github.com/cansyl/DRUIDom.

Synthesis of 7-Chloroquinoline Derivatives Using Mixed Lithium-Magnesium Reagents.

We have prepared a library of functionalized quinolines through the magnesiation of 7-chloroquinolines under mild conditions, employing both batch and continuous flow conditions. The preparation involved the generation of mixed lithium-magnesium intermediates, which were reacted with different electrophiles. Mixed lithium-zinc reagents allowed the synthesis of halogenated and arylated derivatives. Some of the synthesized 4-carbinol quinolines have shown interesting antiproliferative properties, their hydroxyl group being a suitable amino group bioisostere. We also report a two-step approach for optically active derivatives.

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries.

Due to their intrinsic physical properties, which includes being able to perform as volatile liquids at room and biological temperatures, fragrance ingredients/intermediates make ideal candidates for continuous-flow manufacturing. This review highlights the potential crossover between a multibillion dollar industry and the flourishing sub-field of flow chemistry evolving within the discipline of organic synthesis. This is illustrated through selected examples of industrially important transformations specific to the fragrances and flavours industry and by highlighting the advantages of conducting these transformations by using a flow approach. This review is designed to be a compendium of techniques and apparatus already published in the chemical and engineering literature which would constitute a known solution or inspiration for commonly encountered procedures in the manufacture of fragrance and flavour chemicals.

Straight Forward and Versatile Differentiation of the l-glycero and d-glycero-d-manno Heptose Scaffold.

Bacterial lipopolysaccharides (LPS) are important bio-medical structures, playing a major role in the interaction with human immune systems. Their core regions, containing multiple units of l-glycero-d-manno heptoses (l,d-heptose), are highly conserved structurally (with O3 and O7 glycosidic bonds), making them an epitope of high interest for the potential development of new antibiotics and vaccines. Research in this field has always been restricted by the limited availability of the parent l,d-heptose as well as its biochemical epimeric precursor d-glycero-d-manno heptose (d,d-heptose). This problem of availability has recently been solved by us, through a rapid and efficient practical synthesis of l,d-manno-heptose peracetate demonstrated at scale. Herein we report an optimized, technically simple and versatile synthetic strategy for the differentiation of both the l-glycero and d-glycero-d-manno heptose scaffolds. Our approach is based on an orthoester methodology for the differentiation of all three positions of the sugar core using a O6, O7-tetraisopropyl disiloxyl (TIPDS) protecting group for the exocyclic positions. Furthermore, the regioselective opening toward 7-OH acceptors (6O-FTIPDS ethers) differentiates the exocyclic diol which has been demonstrated with a broader set of substrates and for both manno-heptoses for the first time.

A One-Pot Divergent Sequence to Pyrazole and Quinoline Derivatives.

The hydroxy-pyrazole and 3-hydroxy-oxindole motifs have been utilised in several pharma and agrochemical leads but are distinctly underrepresented in the scientific literature due to the limited routes of preparation. We have developed a one-pot procedure for their synthesis starting from simple isatins. The method employs cheap and easy-to-handle building blocks and allows easy isolation.

Rearrangement of 3-Hydroxyazetidines into 2-Oxazolines.

A novel rearrangement sequence of 3-hydroxyazetidines via a Ritter initiated cascade provides highly substituted 2-oxazolines in high yields. The reaction conditions and substrate scope of the transformation have been studied demonstrating the generality of the process. The derived products can also be functionalized in order to undergo further intramolecular cyclization leading to a new class of macrocycle. The final cyclization step was shown to be a transformation amenable to continuous flow processing allowing for a dramatic reduction in the reaction time and simple scale-up.

Copper-Mediated Nitrosation: 2-Nitrosophenolato Complexes and Their Use in the Synthesis of Heterocycles.

A simple protocol yielding ortho-substituted nitrosophenols from phenols is demonstrated, in the form of copper(II) bis(nitrosophenolato) complexes. The developed methodology was applied to a range of substrates, confirming the role of the copper in both the formation and protection of the challenging 1, 2-substitution pattern. Using polymer supported thiourea, the Cu could be stripped from the complexes and thus enabled the isolation or identification of the uncoordinated ligands and their decomposition products, in yields generally low in line with the intrinsic high reactivity of 2-nitrosophenols. The product complexes are useful intermediates as demonstrated in revisiting a formal [4 + 2] cycloaddition with dimethylacetylene dicarboxylate to synthesise bicyclic products in variable yields, revealing the product has a novel structure different from those previously reported in the literature.

The Synthesis and Utility of Metal-Nitrosophenolato Compounds-Highlighting the Baudisch Reaction.

The syntheses of the title compounds demonstrate a privileged introduction of a nitroso (and a hydroxyl via the Baudisch reaction) group to an aromatic ring. These complexes first appeared in the literature as early as 1939, and a range of applications has subsequently been published. However, optimisations of the preparative sequences were not considered, and as such, the reactions have seldom been utilised in recent years; indeed, there remains confusion in the literature as to how such complexes form. In this review, we aim to demystify the misunderstanding surrounding these remarkable complexes and consider their renewed application in the 21st century.

Flow Hydrodediazoniation of Aromatic Heterocycles.

Continuous flow processing was applied for the rapid replacement of an aromatic amino group with a hydride. The approach was applied to a range of aromatic heterocycles, confirming the wide scope and substituent-tolerance of the processes. Flow equipment was utilized and the process optimised to overcome the problematically-unstable intermediates that have restricted yields in previous studies relying on batch procedures. Various common organic solvents were investigated as potential hydride sources. The approach has allowed key structures, such as amino-pyrazoles and aminopyridines, to be deaminated in good yield using a purely organic-soluble system.

Synthesis of new derivatives of boehmeriasin A and their biological evaluation in liver cancer.

Two series of boehmeriasin A analogs have been synthesized in short and high yielding processes providing derivatives differing either in the alkaloid's pentacyclic scaffold or its peripheral substitution pattern. These series have enabled, for the first time, comparative studies into key biological properties revealing a new lead compound with exceptionally high activity against liver cancer cell lines in the picomolar range for both well (Huh7, Hep3B and HepG2) and poorly (Mahlavu, FOCUS and SNU475) differentiated cells. The cell death was characterized as apoptosis by cytochrome-C release, PARP protein cleavage and SubG1 cell cycle arrest. Subsequent testing associated apoptosis via oxidative stress with in situ formation of reactive oxygen species (ROS) and altered phospho-protein levels. Compound 19 decreased Akt protein phosphorylation which is crucially involved in liver cancer tumorigenesis. Given its simple synthetic accessibility and intriguing biological properties this new lead compound could address unmet challenges within liver cancer therapy.

A solid-supported arylboronic acid catalyst for direct amidation.

An efficient heterogeneous amidation catalyst has been prepared by co-polymerisation of styrene, DVB with 4-styreneboronic acid, which shows wide substrate applicability and higher reactivity than the equivalent homogeneous phenylboronic acid, suggesting potential cooperative catalytic effects. The catalyst can be easily recovered and reused; suitable for use in packed bed flow reactors.

Methyl glycosides via Fischer glycosylation: translation from batch microwave to continuous flow processing.

ABSTRACT: A continuous flow procedure for the synthesis of methyl glycosides (Fischer glycosylation) of various monosaccharides using a heterogenous catalyst has been developed. In-depth analysis of the isomeric composition was undertaken and high consistency with corresponding results observed under microwave heating was obtained. Even in cases where addition of water was needed to achieve homogeneity-a prerequisite for the flow experiments-no detrimental effect on the conversion was found. The scalability was demonstrated on a model case (mannose) and as part of the target-oriented synthesis of d-glycero-d-manno heptose, both performed on multigram scale.

Indium- and Zinc-Mediated Acyloxyallylation of Protected and Unprotected Aldotetroses-Revealing a Pronounced Diastereodivergence and a Fundamental Difference in the Performance of the Mediating Metal.

The acyloxyallylation of unprotected aldoses was first demonstrated more than a decade ago as a potentially elegant two-carbon homologation of reducing sugars (upon ozonolysis); however, its application in real case syntheses remained scarce. Following up on such a successful showcase and to answer several pending questions about this attractive transformation, we engaged in an in depth methodological reinvestigation. The epimeric tetroses l-erythrose and d-threose in unprotected and protected form were successfully applied to the indium and also zinc-mediated acyloxyallylation, with the latter being a first for an unprotected sugar. The investigation largely benefited from the choice of these more exotic starting materials as it allowed unambiguous identification/quantification of the hexose-products which are available as authentic reference materials. The observed diastereoselectivities indicate a strong substrate control (stereochemistry at O2), and the influence of the reagent's structure on the selectivity was investigated in great detail. A strong facial diastereodivergence between related protected and unprotected structures was demonstrated and an unexpected, pronounced principle difference in performance between indium and zinc was revealed.

A concise flow synthesis of indole-3-carboxylic ester and its derivatisation to an auxin mimic.

An assembled suite of flow-based transformations have been used to rapidly scale-up the production of a novel auxin mimic-based herbicide which was required for preliminary field trials. The overall synthetic approach and optimisation studies are described along with a full description of the final reactor configurations employed for the synthesis as well as the downstream processing of the reaction streams.

A continuous flow synthesis and derivatization of 1,2,4-thiadiazoles.

A continuous flow process is presented that enables the efficient synthesis and derivatization of 1,2,4-thiadiazole heterocycles. Special attention was given to the safe handling of the versatile yet hazardous trichloromethane sulfenylchloride reagent including its in-line quenching in order to eliminate malodourous and corrosive by-products. Based on this flow method gram quantities of 5-chloro-3-phenyl-1,2,4-thiadiazole were safely prepared allowing for further elaboration of this valuable building block by reaction with different nitrogen-, sulfur- and oxygen-based nucleophiles. This synthetic approach was subsequently applied to generate a series of bromophenyl-5-chloro-1,2,4-thiadiazoles providing a valuable entry towards further structural diversification on this important heterocyclic scaffold.

Diastereoselective Trifluoroacetylation of Highly Substituted Pyrrolidines by a Dakin-West Process.

A robust approach allowing for the efficient trifluoroacetylation of a series of highly substituted pyrrolidines in a diastereoselective manner is reported. The transformation is based on a Dakin-West reaction of advanced pyrrolidine 2-carboxylic acid derivatives that can be assembled stereoselectively in four synthetic steps. Importantly, this work demonstrates how the introduction of lateral substituents on the pyrrolidine scaffold enables the generation of the desired trifluoroacetylation products, which was not possible previously due to the exclusive formation of trifluoromethylated oxazoles (vide infra). In the course of this work we succeeded for the first time in isolating and characterizing (HRMS, IR, 1H, 13C and 19F NMR, X-ray) different intermediates of the Dakin-West reaction allowing us to probe its mechanism.

Flow carbonylation of sterically hindered ortho-substituted iodoarenes.

The flow synthesis of ortho-substituted carboxylic acids, using carbon monoxide gas, has been studied for a number of substrates. The optimised conditions make use of a simple catalyst system compromising of triphenylphosphine as the ligand and palladium acetate as the pre-catalyst. Carbon monoxide was introduced via a reverse "tube-in-tube" flow reactor at elevated pressures to give yields of carboxylated products that are much higher than those obtained under normal batch conditions.