A fluorescent probe for detection of Hg²⁺ ions constructed by tetramethyl cucurbit[6]uril and 1,2-bis(4-pyridyl)ethene

• Xiaoqian Chen,
• Naqin Yang,
• Yue Ma,
• Xinan Yang and
• Peihua Ma

Beilstein J. Org. Chem. 2023, 19, 864–872, doi:10.3762/bjoc.19.63

• = 0.9926, and the limit of detection is 4.12 × 10−8 mol·L−1. The fluorescent probe can be used to detect the concentration of Hg2+ ions in aqueous solution, and provides a theoretical basis for the development of new fluorescent probes for detecting heavy metal ions. Keywords: 1,2-bis(4-pyridyl)ethane

• cucurbit[n]uril fluorescent probes has become increasingly mature [9][28][29][30][31]. For example, the host–guest fluorescent probe of cucurbit[10]uril (Q[10]) and the fluorescent dye acridine (AD) was used to identify the pesticide dodine (DD) [32]; a fluorescent probe of cucurbit[10]uril (Q[10]) and

• , which provides convenience for studying the host–guest chemistry of TMeQ[6] and constructing fluorescent probes in aqueous solution [37][38]. There is a π–π conjugation effect between the carbon–carbon double bond and the pyridine ring in 1,2-bis(4-pyridyl)ethene (G), which determines its ultraviolet

pH-Responsive fluorescent supramolecular nanoparticles based on tetraphenylethylene-labelled chitosan and a six-fold carboxylated tribenzotriquinacene

• Nan Yang,
• Yi-Yan Zhu,
• Wei-Xiu Lin,
• Yi-Long Lu and
• Wen-Rong Xu

Beilstein J. Org. Chem. 2023, 19, 635–645, doi:10.3762/bjoc.19.45

• larger than those measured by TEM. This is because TEM probes samples in the dry state, while DLS examines samples in the solvated state, where the solvent molecules are associated with the nanoparticles. The zeta potentials of these three TBTQ-C6/CS-TPE nanoparticles were further measured to determine

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

• RNA, single or double-stranded polynucleotides, particular base composition…) and signalize binding by specific spectroscopic response is of great importance [1][2]. Pyrene derivatives are among the earliest known fluorescent probes for biomolecules. These chromophores are often used due to their high

• 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

• sensitivity to the polarity of its surroundings. Similar as pyrenes, phenanthridines are also used as fluorescent probes, and their characteristics may be altered by various substituents appended to the aromatic core. The formation of excimers by two or more pyrenes is well known in the literature [4

CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview

• Dileep Kumar Singh

Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29

• well as optical properties. Moreover, the versatility of coumarin hybrids finds numerous applications including fluorescent brightening agents [16], optical sensors [17], organic light emitting diodes [18][19], light harvesting materials [20] and fluorescent probes in biological imaging [21]. Therefore

1,4-Dithianes: attractive C2-building blocks for the synthesis of complex molecular architectures

• Bram Ryckaert,
• Ellen Demeyere,
• Frederick Degroote,
• Hilde Janssens and
• Johan M. Winne

Beilstein J. Org. Chem. 2023, 19, 115–132, doi:10.3762/bjoc.19.12

• probes that indicated the carbocationic nature of the involved intermediate species. Spurred by our results in (3 + 2) cycloadditions of 1,4-dithiane-fused allyl cations (vide supra) [103], our group recently investigated the use of Wang’s soft activation mode of 1,4-dithiane-fused allyl cations for its

Revisiting the bromination of 3β-hydroxycholest-5-ene with CBr₄/PPh₃ and the subsequent azidolysis of the resulting bromide, disparity in stereochemical behavior

• Christian Schumacher,
• Jas S. Ward,
• Kari Rissanen,
• Carsten Bolm and
• Mohamed Ramadan El Sayed Aly

Beilstein J. Org. Chem. 2023, 19, 91–99, doi:10.3762/bjoc.19.9

• -azidocholest-5-ene (5) in high yield. The same product was recently obtained by direct dehydroxyazidation of cholesterol upon treatment with N-acetyl azidobenziodazolone (ABZ) and PPh3 in THF [19], Table 1. While synthesizing new potential biologically active probes with cholesterol scaffolds in the Port Said

A novel spirocyclic scaffold accessed via tandem Claisen rearrangement/intramolecular oxa-Michael addition

• Anastasia Vepreva,
• Alexander Yanovich,
• Dmitry Dar’in,
• Grigory Kantin,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1649–1655, doi:10.3762/bjoc.18.177

• adenocarcinoma) and NCI-H460 (lung cancer) cell lines and proved completely non-cytotoxic. This validates these new compounds as suitable molecular probes for interrogating various biological targets via screening in cell-based assays. Conclusion We have developed a straightforward access to novel spiro

A novel bis-triazole scaffold accessed via two tandem [3 + 2] cycloaddition events including an uncatalyzed, room temperature azide–alkyne click reaction

• Ksenia Malkova,
• Andrey Bubyrev,
• Vasilisa Krivovicheva,
• Dmitry Dar’in,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1636–1641, doi:10.3762/bjoc.18.175

• on cell proliferation in concentrations up to 250 μM. This validates these novel compounds as non-cytotoxic probes for interrogation of various biological targets. Conclusion The previously described α-acetyl-α-diazomethanesulfonamide was employed in a three-component reaction with azide-containing

New triazole-substituted triterpene derivatives exhibiting anti-RSV activity: synthesis, biological evaluation, and molecular modeling

• Elenilson F. da Silva,
• Krist Helen Antunes Fernandes,
• Denise Diedrich,
• Jessica Gotardi,
• Marcia Silvana Freire Franco,
• Carlos Henrique Tomich de Paula da Silva,
• Ana Paula Duarte de Souza and
• Simone Cristina Baggio Gnoatto

Beilstein J. Org. Chem. 2022, 18, 1524–1531, doi:10.3762/bjoc.18.161

• probes: forward, 5'-AACAGATGTAAGCAGCTCCGTTATC-3'; reverse, 5'-GATTTTTATTGGATGCTGTACATTT-3'; and probe, 5'-FAM/TGCCATAGCATGACACAATGGCTCCT-TAMRA/-3', using human β-actin as an endogenous control gene using the TaqMan assay [43]. The delta cycle-threshold (ΔCt) was obtained by subtracting the endogenous

Microelectrode arrays, electrosynthesis, and the optimization of signaling on an inert, stable surface

• Kendra Drayton-White,
• Siyue Liu,
• Yu-Chia Chang,
• Sakashi Uppal and
• Kevin D. Moeller

Beilstein J. Org. Chem. 2022, 18, 1488–1498, doi:10.3762/bjoc.18.156

• solution and recording the corresponding change in current, a binding curve for the interaction can be generated. While this approach can be very effective, it has limitations. We are interested in using microelectrode arrays to guide synthetic efforts to build molecular probes for protein active sites

Mechanochemical synthesis of unsymmetrical salens for the preparation of Co–salen complexes and their evaluation as catalysts for the synthesis of α-aryloxy alcohols via asymmetric phenolic kinetic resolution of terminal epoxides

• Shengli Zuo,
• Shuxiang Zheng,
• Jianjun Liu and
• Ang Zuo

Beilstein J. Org. Chem. 2022, 18, 1416–1423, doi:10.3762/bjoc.18.147

• addition, a Lewis basic NEt2 (‒N(CH2CH3)2) group was introduced to the salen scaffold to facilitate purification, enhance catalytic efficiency, and improve the thermal stability, as was shown in the synthesis of fluorescent probes [41][42]. The chelating effect of salen compounds 1 with different metals

Synthesis of C6-modified mannose 1-phosphates and evaluation of derived sugar nucleotides against GDP-mannose dehydrogenase

• Sanaz Ahmadipour,
• Alice J. C. Wahart,
• Jonathan P. Dolan,
• Laura Beswick,
• Chris S. Hawes,
• Robert A. Field and
• Gavin J. Miller

Beilstein J. Org. Chem. 2022, 18, 1379–1384, doi:10.3762/bjoc.18.142

• inhibitors to disrupt bacterial alginate production [3]. We recently disclosed the first series of targeted sugar nucleotide probes for GMD (Figure 1b) [4][5][6]. A C6-methyl analogue 6 was oxidised by GMD with direct evidence for a ketone product obtained. Most recently, C6-amide sugar nucleotide 7 was

• Chemical synthesis of 6-chloro-6-deoxy- and 6-amino-6-deoxy-mannose 1-phosphates We first required access to appropriate glycosyl 1-phosphates (as putative substrates for enzymatic pyrophosphorylative coupling) to then access the sugar nucleotide GMD probes of type 8 and 9 (Figure 1c). Accordingly

On drug discovery against infectious diseases and academic medicinal chemistry contributions

• Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 1355–1378, doi:10.3762/bjoc.18.141

• sciences: – The development of genetics and molecular biology leading, with or without the use of chemical probes [1], to the discovery of a near infinite number of biochemical processes, amenable to the design of assays as plausible targets for drug discovery programs. – The development of robotics and

• chances of being identified in the course of screenings. In 2004, the Molecular Library Initiative sponsored by the NIH also tried to address such issues and provide probes to determine the function and therapeutic potential of all the human genes. Aside from considerations on the selectivity and drug

Computational model predicts protein binding sites of a luminescent ligand equipped with guanidiniocarbonyl-pyrrole groups

• Neda Rafieiolhosseini,
• Matthias Killa,
• Thorben Neumann,
• Niklas Tötsch,
• Jean-Noël Grad,
• Alexander Höing,
• Thies Dirksmeyer,
• Jochen Niemeyer,
• Christian Ottmann,
• Shirley K. Knauer,
• Michael Giese,
• Jens Voskuhl and
• Daniel Hoffmann

Beilstein J. Org. Chem. 2022, 18, 1322–1331, doi:10.3762/bjoc.18.137

• electrostatic potential grid into energy grids suitable for the Hamiltonian, chemically relevant polymer fragments were used as molecular probes in Epitopsy [26]. Epitopsy is a tool designed to calculate the electrostatic energy of a protein–ligand system from the protein potential grid and ligand charge

Polymer and small molecule mechanochemistry: closer than ever

• José G. Hernández

Beilstein J. Org. Chem. 2022, 18, 1225–1235, doi:10.3762/bjoc.18.128

• time, two main experimental strategies to produce physical and chemical responses in a system when mechanical force is applied have been established. One of them, often called polymer mechanochemistry, relies on the use of polymers to transduce mechanical loads to mechanically sensitive probes

Scope of tetrazolo[1,5-a]quinoxalines in CuAAC reactions for the synthesis of triazoloquinoxalines, imidazoloquinoxalines, and rhenium complexes thereof

• Laura Holzhauer,
• Chloé Liagre,
• Olaf Fuhr,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2022, 18, 1088–1099, doi:10.3762/bjoc.18.111

• diversity of metal complexes incorporating 1,2,3-triazoles as ligands have been reported [16][17][18]. Triazole ligands with N-heterocycles such as Pyta (4-(2-pyridyl)-1,2,3-triazole) and related structures were employed to obtain novel metal complexes as catalysts [19][20] and imaging probes [21], as well

• especially used as CO2 reduction catalysts [38][39][40] and noninvasive imaging probes [12][41]; examples for the application in organic light-emitting diodes [35] and as photoactive CO-releasing molecule [42][43] have been reported as well. For the complexation experiments, compounds with three different

Facile and diastereoselective arylation of the privileged 1,4-dihydroisoquinolin-3(2H)-one scaffold

• Dmitry Dar’in,
• Grigory Kantin,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1070–1078, doi:10.3762/bjoc.18.109

• -DHIQ adducts synthesized in this work, they were deemed efficient probes for the perturbation of vital cellular targets. Screening of these compounds against lung carcinoma cancer cell lines confirmed high cytotoxicity of selected analogs, which validates this new chemotype for further investigation as

Synthesis, optical and electrochemical properties of (D–π)₂-type and (D–π)₂Ph-type fluorescent dyes

• Kosuke Takemura,
• Kazuki Ohira,
• Taiki Higashino,
• Keiichi Imato and
• Yousuke Ooyama

Beilstein J. Org. Chem. 2022, 18, 1047–1054, doi:10.3762/bjoc.18.106

• ][16][17][18][19][20][21][22], as well as fluorescent probes [23][24][25][26][27][28] for bioimaging and fluorescent sensors for specific target species [29][30][31][32]. Among many kinds of organic fluorescent dyes, much efforts have been made on the development of donor–π–acceptor (D–π–A)-type

New azodyrecins identified by a genome mining-directed reactivity-based screening

• Atina Rizkiya Choirunnisa,
• Kuga Arima,
• Yo Abe,
• Noritaka Kagaya,
• Kei Kudo,
• Hikaru Suenaga,
• Junko Hashimoto,
• Manabu Fujie,
• Noriyuki Satoh,
• Kazuo Shin-ya,
• Kenichi Matsuda and
• Toshiyuki Wakimoto

Beilstein J. Org. Chem. 2022, 18, 1017–1025, doi:10.3762/bjoc.18.102

• natural products, despite their notable biological activities. Reactivity-based screening is an emerging strategy in natural products discovery, in which chemical probes are used for the specific detection of the unique functionality of interest in crude metabolites [5][6]. The reactions usually

Syntheses of novel pyridine-based low-molecular-weight luminogens possessing aggregation-induced emission enhancement (AIEE) properties

• Masayori Hagimori,
• Tatsusada Yoshida,
• Yasuhisa Nishimura,
• Yukiko Ogawa and
• Keitaro Tanaka

Beilstein J. Org. Chem. 2022, 18, 580–587, doi:10.3762/bjoc.18.60

• have been reported [7][8][9][10]. Because the aggregated state of AIEE-based compounds is affected by the external environment, these compounds have found use in clinical applications as chemical sensors or fluorescent probes [7][8][9][10]. Pyridine is a nitrogen-containing heterocyclic compound found

Comparative study of thermally activated delayed fluorescent properties of donor–acceptor and donor–acceptor–donor architectures based on phenoxazine and dibenzo[a,j]phenazine

• Saika Izumi,
• Prasannamani Govindharaj,
• Anna Drewniak,
• Paola Zimmermann Crocomo,
• Satoshi Minakata,
• Leonardo Evaristo de Sousa,
• Piotr de Silva,
• Przemyslaw Data and
• Youhei Takeda

Beilstein J. Org. Chem. 2022, 18, 459–468, doi:10.3762/bjoc.18.48

• organic light-emitting diodes (OLEDs) by Adachi in 2012 [2], TADF-active compounds have emerged as emitters in high-performance organic light-emitting diodes (OLEDs) [3][4][5][6][7][8], biological probes [9], photocatalysis [10], and some others [11]. Specifically, TADF-active purely organic compounds

The role of chemistry in the success of oligonucleotides as therapeutics

• Pawan Kumar and
• Tom Brown

Beilstein J. Org. Chem. 2022, 18, 197–199, doi:10.3762/bjoc.18.22

• oligonucleotide primers and probes for use in diagnostic testing kits for the detection of COVID-19 for tackling the pandemic. With this thematic issue, we express our sincere gratitude to all the scientists for their ground-breaking work to bring oligonucleotide therapeutics to the bedside. We also express our

Synthetic strategies toward 1,3-oxathiolane nucleoside analogues

• Umesh P. Aher,
• Dhananjai Srivastava,
• Girij P. Singh and
• Jayashree B. S

Beilstein J. Org. Chem. 2021, 17, 2680–2715, doi:10.3762/bjoc.17.182

• Academy of Higher Education, Manipal-576104, Karnataka, India 10.3762/bjoc.17.182 Abstract Sugar-modified nucleosides have gained considerable attention in the scientific community, either for use as molecular probes or as therapeutic agents. When the methylene group of the ribose ring is replaced with a

Progress and challenges in the synthesis of sequence controlled polysaccharides

• Giulio Fittolani,
• Theodore Tyrikos-Ergas,
• Denisa Vargová,
• Manishkumar A. Chaube and
• Martina Delbianco

Beilstein J. Org. Chem. 2021, 17, 1981–2025, doi:10.3762/bjoc.17.129

• are ideal probes to study polysaccharides at the molecular level and identify structure–property correlations. Access to synthetic polysaccharides facilitated the correlation of chemical structure with molecular conformations [5][6], intermolecular interactions [7][8], and biological response [9

Asymmetric organocatalyzed synthesis of coumarin derivatives

• Natália M. Moreira,
• Lorena S. R. Martelli and
• Arlene G. Corrêa

Beilstein J. Org. Chem. 2021, 17, 1952–1980, doi:10.3762/bjoc.17.128

• acetylcholinesterase inhibitors [11][12][13], being LSPN223 the most potent compound (Figure 2). Furthermore, coumarin derivatives have been used as fluorescent probes, laser dyes, fluorescent chemosensors, light absorbers for solar cells, optical brighteners, and organic light emitting diodes (OLEDs) [14][15]. From a