Green and sustainable approaches for the Friedel–Crafts reaction between aldehydes and indoles

• Periklis X. Kolagkis,
• Eirini M. Galathri and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2024, 20, 379–426, doi:10.3762/bjoc.20.36

• cruciferous vegetables, as hydrolysis products from the metabolism of glucosinolates [1]. In 2017, Müller and her research team showcased the ability of BIMs to operate as anti-inflammatory drugs by acting as GPR84 agonists [2]. GPR84 is a protein-coupled receptor found in immune cells, which regulates a

• related environments [8]. The mechanism of action involves the binding of BIMs to the penicillin-restricting protein PBP2a which inhibits the biosynthesis of the bacterial cell wall, making the treatment feasible without any toxicity to human cells [9][10]. The applications of BIMs have also been extended

Discovery of unguisin J, a new cyclic peptide from Aspergillus heteromorphus CBS 117.55, and phylogeny-based bioinformatic analysis of UngA NRPS domains

• Sharmila Neupane,
• Marcelo Rodrigues de Amorim and
• Elizabeth Skellam

Beilstein J. Org. Chem. 2024, 20, 321–330, doi:10.3762/bjoc.20.32

• genome was initially screened using fungiSMASH to identify scaffolds/contigs encoding secondary metabolites. Scaffold MSFL01000005.1 was further investigated using FGENESH [17] to further refine gene boundaries, introns, and resulting protein sequence (Table S1, Supporting Information File 1

Elucidating the glycan-binding specificity and structure of Cucumis melo agglutinin, a new R-type lectin

• Jon Lundstrøm,
• Emilie Gillon,
• Valérie Chazalet,
• Nicole Kerekes,
• Antonio Di Maio,
• Ten Feizi,
• Yan Liu,
• Annabelle Varrot and
• Daniel Bojar

Beilstein J. Org. Chem. 2024, 20, 306–320, doi:10.3762/bjoc.20.31

• member of characterized melon lectins, namely the Cucumis melo agglutinin (CMA1), an R-type lectin derived from melon. Prior to our study, CMA1 was only a predicted protein from genomic sequencing, with moderate certainty scores on lectin-specific databases. Our comprehensive analysis using glycan array

• unique binding profile of specifically recognizing C2-substituted galactose in the context of glycans. Results and Discussion Identification and production of a new lectin from the melon Cucumis melo CMA1 is a predicted protein from whole-genome shotgun sequencing of leaves from the melon plant Cucumis

• , as an archetypal example of melon lectins. For this, we needed to express the lectin recombinantly. As it is a secreted plant protein, we elected to express it in mammalian cell lines, to maximize the chances of a functional protein, because of post-translational modifications that would be lacking

Visible-light-induced radical cascade cyclization: a catalyst-free synthetic approach to trifluoromethylated heterocycles

• Chuan Yang,
• Wei Shi,
• Jian Tian,
• Lin Guo,
• Yating Zhao and
• Wujiong Xia

Beilstein J. Org. Chem. 2024, 20, 118–124, doi:10.3762/bjoc.20.12

• compounds (Figure 1) [1][2][3], which exhibit a wide range of biological and pharmaceutical activities [4]. For example, mersicarpine has been found to inhibit protein translation and induce apoptosis [5] and vinburnine acts as a vasodilator for the treatment of cerebrovascular insufficiency [6][7]. Given

Identification of the p-coumaric acid biosynthetic gene cluster in Kutzneria albida: insights into the diazotization-dependent deamination pathway

• Seiji Kawai,
• Akito Yamada,
• Yohei Katsuyama and
• Yasuo Ohnishi

Beilstein J. Org. Chem. 2024, 20, 1–11, doi:10.3762/bjoc.20.1

• recent studies [9][10][11][12][13][14]. Most of them belong to the adenylate-forming enzyme superfamily (ANL superfamily) and utilize ATP to activate nitrous acid by AMPylation, with the only exception being AzpL in alazopeptin biosynthesis, which is a membrane protein that catalyzes diazotization

• biosynthetic pathway [13]. In this pathway, 3-amino-4-hydroxybenzoic acid (3,4-AHBA, 1), synthesized by AvaH and AvaI, is loaded onto AvaA3 (carrier protein) by AvaA1 (AMP-dependent ligase), resulting in 3,4-AHBA-AvaA3. A highly reducing type II polyketide synthase (PKS) system [15][16] (AvaA2, A4, A5, and A8

• insights into how highly reducing type II PKSs control starter substrate incorporation. The only difference between avenalumic acid and p-coumaric acid is the chain length. The CLF CmaA5 shows 35.4% identity to AvaA5, which is the lowest similarity score among Ava and Cma protein pairs (Table 1). This is

Long oligodeoxynucleotides: chemical synthesis, isolation via catching-by-polymerization, verification via sequencing, and gene expression demonstration

• Yipeng Yin,
• Reed Arneson,
• Alexander Apostle,
• Adikari M. D. N. Eriyagama,
• Komal Chillar,
• Emma Burke,
• Martina Jahfetson,
• Yinan Yuan and
• Shiyue Fang

Beilstein J. Org. Chem. 2023, 19, 1957–1965, doi:10.3762/bjoc.19.146

• ligation from shorter 20 to 60 nt ODNs produced by automated de novo chemical synthesis. While these methods have made many projects in areas such as synthetic biology and protein engineering possible, they have various drawbacks. For example, they cannot produce genes and genomes with long repeats and

• 401 nt ODNs were synthesized and purified with CBP. The two were joined together using Gibson assembly to give the 800 nt green fluorescent protein (GFP) gene construct. The sequence of the construct was verified via Sanger sequencing. To demonstrate the potential use of the long ODN synthesis method

• . Keywords: automated synthesis; catching-by-polymerization; gene assembly; long oligonucleotide; synthetic biology; Introduction Long oligodeoxynucleotides (ODNs) are segments of DNAs extending beyond one hundred nucleotides (nt). Emerging research areas such as synthetic biology [1][2], protein

Studying specificity in protein–glycosaminoglycan recognition with umbrella sampling

• Mateusz Marcisz,
• Sebastian Anila,
• Margrethe Gaardløs,
• Martin Zacharias and
• Sergey A. Samsonov

Beilstein J. Org. Chem. 2023, 19, 1933–1946, doi:10.3762/bjoc.19.144

• proteins. The structural and functional heterogeneities of GAGs as well as their ability to bind specific proteins are determined by the sugar composition of the GAG, the size of the GAG chains, and the degree and pattern of sulfation. A deep understanding of the interactions in protein–GAG complexes is

• GAG properties, especially protein recognition specificity and multipose binding. We found that the binding free energy landscape in the proximity of the GAG native binding pose is complex and implies the co-existence of several binding poses. The sliding of a GAG chain along a protein surface could

• be a potential mechanism of GAG particular sequence recognition by proteins. Keywords: glycosaminoglycan; molecular docking; protein–glycosaminoglycan interaction specificity; RS-REMD; umbrella sampling; Introduction Glycosaminoglycans (GAGs) are long linear periodic anionic polydisperse

N-Boc-α-diazo glutarimide as efficient reagent for assembling N-heterocycle-glutarimide diads via Rh(II)-catalyzed N–H insertion reaction

• Grigory Kantin,
• Pavel Golubev,
• Alexander Sapegin,
• Alexander Bunev and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2023, 19, 1841–1848, doi:10.3762/bjoc.19.136

• ; Introduction Targeted protein degradation (TPD) has transformed the field of drug discovery [1][2]. Utilizing proximity-induced pharmacological strategies [3], this method has fostered the creation of numerous molecular glues and proteolysis-targeting chimeras (PROTACs). By manipulation of the internal

GlAIcomics: a deep neural network classifier for spectroscopy-augmented mass spectrometric glycans data

• Thomas Barillot,
• Baptiste Schindler,
• Baptiste Moge,
• Elisa Fadda,
• Franck Lépine and
• Isabelle Compagnon

Beilstein J. Org. Chem. 2023, 19, 1825–1831, doi:10.3762/bjoc.19.134

• intelligence in combination with spectroscopy-augmented mass spectrometry for carbohydrates sequencing and glycomics applications. Keywords: Bayesian neural network; deep learning; glycomics; IR; spectroscopy; Introduction DNA and protein sequencing technologies that aim at determining the structure of a

Effects of the aldehyde-derived ring substituent on the properties of two new bioinspired trimethoxybenzoylhydrazones: methyl vs nitro groups

• Dayanne Martins,
• Roberta Lamosa,
• Talis Uelisson da Silva,
• Carolina B. P. Ligiero,
• Sérgio de Paula Machado,
• Daphne S. Cukierman and
• Nicolás A. Rey

Beilstein J. Org. Chem. 2023, 19, 1713–1727, doi:10.3762/bjoc.19.125

• first to establish the suitability of N-acylhydrazones as novel metallophores able to affect protein aggregation and/or oxidation enhanced by physiological metal–protein anomalous interactions related to Alzheimer's (AD) and Parkinson's (PD), as well as to prion diseases [27][28][29][30][31][32][33][34

Sulfur-containing spiroketals from Breynia disticha and evaluations of their anti-inflammatory effect

• Ken-ichi Nakashima,
• Naohito Abe,
• Masayoshi Oyama,
• Hiroko Murata and
• Makoto Inoue

Beilstein J. Org. Chem. 2023, 19, 1604–1614, doi:10.3762/bjoc.19.117

• -stimulated increase in IL-1β and IL-6 production was suppressed by compound 7 at a concentration of 10 μM (Figure 6f and 6g). Thus, compound 7 inhibited LPS-stimulated IL-1β and IL-6 mRNA and protein expression in RAW 264.7 cells. Although confirmed only at the mRNA level, 1, 2, and 6 likely exhibit similar

Synthesis and biological evaluation of Argemone mexicana-inspired antimicrobials

• Jessica Villegas,
• Bryce C. Ball,
• Katelyn M. Shouse,
• Caleb W. VanArragon,
• Ashley N. Wasserman,
• Hannah E. Bhakta,
• Allen G. Oliver,
• Danielle A. Orozco-Nunnelly and
• Jeffrey M. Pruet

Beilstein J. Org. Chem. 2023, 19, 1511–1524, doi:10.3762/bjoc.19.108

• often attributed to high binding affinity to DNA, interference with protein biosynthesis, induction of membrane leakage, and affecting GTPase activity in bacteria cell division [12][13][14][15]. Recent reports have also pointed to inhibition of the ‘filamenting temperature-sensitive mutant Z’ (FtsZ

• ) protein [16][17], as well as perturbing carbohydrate metabolism to generate reactive oxygen species that damage the DNA [18], as modes of action for berberine’s antibacterial effects. The antitumor properties of berberine have been attributed to DNA binding, and in particular regulating the activity of

• ]. Similar to berberine, results have demonstrated that the antibacterial activity of chelerythrine can be tied to DNA intercalation and disruption to cell membrane permeability [11][24]. One particular mechanism of action noted for chelerythrine’s antitumor bioactivity is through the inhibition of protein

Functions of enzyme domains in 2-methylisoborneol biosynthesis and enzymatic synthesis of non-natural analogs

• Binbin Gu,
• Lin-Fu Liang and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2023, 19, 1452–1459, doi:10.3762/bjoc.19.104

• studied. Several 2-methylisoborneol synthases have a proline-rich N-terminal domain of unknown function. The results presented here demonstrate that this domain leads to a reduced enzyme activity, in addition to its ability to increase long-term solubility of the protein. Furthermore, the substrate scope

• elution buffer used for protein purification through Ni2+-NTA affinity chromatography. While domain B alone showed a substantial enzyme precipitation after 12 h at 4 °C, full length 2MIBS did not (Figure 1B), suggesting that the A domain increases enzyme solubility and long-term stability. This effect

• needs a covalent bond between the two domains A and B, as indicated by a similar precipitation of domain B alone and domain B in the presence of domain A. In these experiments, the N-terminal His-tags at both domains A and B may influence protein–protein interaction with the consequence that the mixture

Functional characterisation of twelve terpene synthases from actinobacteria

• Anuj K. Chhalodia,
• Houchao Xu,
• Georges B. Tabekoueng,
• Binbin Gu,
• Kizerbo A. Taizoumbe,
• Lukas Lauterbach and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2023, 19, 1386–1398, doi:10.3762/bjoc.19.100

• Streptomyces cattleya that shows the same sequence deviation in the NSE triad and has 58% identity [49], and to phomopsene synthase from A. albata with 36% identity (Figure S43, Supporting Information File 1) [50]. The incubation of GPP, FPP and GFPP with the purified protein only resulted in acyclic products

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

Cyanothioacetamides as a synthetic platform for the synthesis of aminopyrazole derivatives

• Valeriy O. Filimonov,
• Alexandra I. Topchiy,
• Vladimir G. Ilkin,
• Tetyana V. Beryozkina and
• Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2023, 19, 1191–1197, doi:10.3762/bjoc.19.87

• molecules that attack and destroy lipids and protein membranes of weed cells [10]. Fipronil is an inhibitor of GABA receptors and affects the nervous system of insects as a broad-spectrum insecticide [11][12]. On the other hand, thioamides are an important class of organic compounds. 6-Thioguanine and

Intermediates and shunt products of massiliachelin biosynthesis in Massilia sp. NR 4-1

• Till Steinmetz,
• Blaise Kimbadi Lombe and
• Markus Nett

Beilstein J. Org. Chem. 2023, 19, 909–917, doi:10.3762/bjoc.19.69

• fulfill specific functions, ranging from the selection and linkage of building blocks to their chemical modification. A plausible scenario for the formation of compounds 1–6 involves the enzymatic machinery for massiliachelin biosynthesis, namely the protein RS02200 [18]. According to our proposal (Figure

• protein RS02200: FAAL: fatty acyl-AMP ligase; ACP: acyl carrier protein; KS: β-ketoacyl synthase; AT: acyltransferase; KR: ketoreductase; C: condensation; A: adenylation; MT: methyltransferase; PCP: peptidyl carrier protein. A discrete enzyme, the thiazolinyl imide reductase RS02195 (Red), catalyzes the

Synthesis of aliphatic nitriles from cyclobutanone oxime mediated by sulfuryl fluoride (SO₂F₂)

• Xian-Lin Chen and
• Hua-Li Qin

Beilstein J. Org. Chem. 2023, 19, 901–908, doi:10.3762/bjoc.19.68

• interaction between the drug candidate and the target protein, to further improve the efficacy of the potential drug [9]. The nitrile group can also function as a metabolic blocking site to inhibit the oxidative metabolism of molecules to improve metabolic stability in vivo [10]. Consequently, the development

Light-responsive rotaxane-based materials: inducing motion in the solid state

• Adrian Saura-Sanmartin

Beilstein J. Org. Chem. 2023, 19, 873–880, doi:10.3762/bjoc.19.64

• photodegradation of intertwined gels could lead to advanced functional materials avoiding the UV phototoxicity for biocompatible implementations, such as protein patterning and tissue engineering. Light-responsive metal-organic rotaxane frameworks The integration of the mechanical bond into metal-organic

Non-peptide compounds from Kronopolites svenhedini (Verhoeff) and their antitumor and iNOS inhibitory activities

• Yuan-Nan Yuan,
• Jin-Qiang Li,
• Hong-Bin Fang,
• Shao-Jun Xing,
• Yong-Ming Yan and
• Yong-Xian Cheng

Beilstein J. Org. Chem. 2023, 19, 789–799, doi:10.3762/bjoc.19.59

• using a microplate reader (450 nm, BioTek, USA), and the cell survival rate was calculated. Western blot analysis was used to detect protein levels in cells. RAW264.7 cells were pre-treated with the corresponding concentration of the compound or DMSO for 2 h and then stimulated with lipopolysaccharide

• (LPS, 1 μg/mL) for 12 h. Subsequently, radioimmunoprecipitation assay (RIPA) buffer (Beyotime, PR China) containing a protease inhibitor (Roche, Germany) was used to extract total protein from cells. Protein content samples was determined by the BCA assay (Thermo, USA). Equivalent protein extracts were

• determine the protein levels of iNOS and COX-2, using GAPDH as a control and dexamethasone (DEX) as a positive reference drug. 1H (600 MHz) and 13C NMR (150 MHz) data of compound 1 (δ in ppm, J in Hz, methanol-d4). 1H (600 MHz) and 13C NMR (150 MHz) data of compounds 2 and 3 (δ in ppm, J in Hz, methanol-d4

Synthesis of imidazo[1,2-a]pyridine-containing peptidomimetics by tandem of Groebke–Blackburn–Bienaymé and Ugi reactions

• Oleksandr V. Kolomiiets,
• Alexander V. Tsygankov,
• Maryna N. Kornet,
• Aleksander A. Brazhko,
• Vladimir I. Musatov and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2023, 19, 727–735, doi:10.3762/bjoc.19.53

• viruses, including influenza, SARS-CoV, and SARS-CoV-2, are becoming extremely important. For example, peptidomimetic structures such as lopinavir and ritonavir can inhibit 3CL protease, which is one of the major protein structures encoded by the SARS-CoV-2 genome [20]. Therefore, it is necessary to pay

Palladium-catalyzed enantioselective three-component synthesis of α-arylglycine derivatives from glyoxylic acid, sulfonamides and aryltrifluoroborates

• Bastian Jakob,
• Nico Schneider,
• Luca Gengenbach and
• Georg Manolikakes

Beilstein J. Org. Chem. 2023, 19, 719–726, doi:10.3762/bjoc.19.52

• amino acids received increasing attention due to advances in protein-engineering and the development of protein-based therapeutics [3][4]. Among the different types of non-proteinogenic and unnatural amino acids, α-arylglycines play a particular important role. The arylglycine scaffold can be found in

Nucleophile-induced ring contraction in pyrrolo[2,1-c][1,4]benzothiazines: access to pyrrolo[2,1-b][1,3]benzothiazoles

• Ekaterina A. Lystsova,
• Maksim V. Dmitriev,
• Andrey N. Maslivets and
• Ekaterina E. Khramtsova

Beilstein J. Org. Chem. 2023, 19, 646–657, doi:10.3762/bjoc.19.46

• popular in medicinal chemistry and pharmacology as potential biologically active compounds. In particular, PBTAs were found to be promising inhibitors of centromere-associated protein E (CENP-E) (Figure 1), which is demanded for the development of targeted cancer therapy [1]. Furthermore, candidate

Phenanthridine–pyrene conjugates as fluorescent probes for DNA/RNA and an inactive mutant of dipeptidyl peptidase enzyme

• Josipa Matić,
• Tana Tandarić,
• Marijana Radić Stojković,
• Filip Šupljika,
• Zrinka Karačić,
• Ana Tomašić Paić,
• Lucija Horvat,
• Robert Vianello and
• Lidija-Marija Tumir

Beilstein J. Org. Chem. 2023, 19, 550–565, doi:10.3762/bjoc.19.40

• Biochemistry, Faculty of Food Technology and Biotechnology, University of Zagreb, Croatia Laboratory for Protein Biochemistry and Molecular Modelling, Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia Laboratory for Molecular Plant Biology and

• extinction coefficient and long emission lifetime (>100 ns) [3]. Their large aromatic hydrophobic surface allows the intercalation between DNA/RNA base pairs and binding within the minor groove. Pyrenes are also prominent protein probes that can monitor protein conformational changes because of pyrene

• ) inactive enzyme mutant E451A was examined by fluorimetric titrations and ITC titrations and it was found that Phen-Py-1 binds to the protein with a high affinity (Table 3). This protein is a mono-zinc metalloexopeptidase and hydrolyses dipeptides from the N-termini of substrates that consist of at least

Combretastatins D series and analogues: from isolation, synthetic challenges and biological activities

• Jorge de Lima Neto and
• Paulo Henrique Menezes

Beilstein J. Org. Chem. 2023, 19, 399–427, doi:10.3762/bjoc.19.31

• cancer cell growth when compared with compounds 2 and 28, due the same lack of phosphatase cited before. It is worth to note that the mechanism of action for these compounds is attributed to their ability to interfere in the dynamics of tubulin, a protein involved in the formation of the cytoskeleton