Synthesis, characterization, antimicrobial, cytotoxic and carbonic anhydrase inhibition activities of multifunctional pyrazolo-1,2-benzothiazine acetamides

• Ayesha Saeed,
• Shahana Ehsan,
• Muhammad Zia-ur-Rehman,
• Erin M. Marshall,
• Sandra Loesgen,
• Abdus Saleem,
• Simone Giovannuzzi and
• Claudiu T. Supuran

Beilstein J. Org. Chem. 2025, 21, 348–357, doi:10.3762/bjoc.21.25

• and 13C NMR spectroscopy. All compounds were tested against five human microbial strains including three different strains of Staphylococcus aureus (ATCC 25923, ATCC BAA-41, and ATCC BAA-44), Escherichia coli (ATCC 8739), and Candida albicans (ATCC 90027) to evaluate their antibiotic potential. The

• are synthesized by incorporation of benzothiazine, pyrazole, and amide moieties in a new scaffold to create multifunctional derivatives of pyrazolo-1,2-benzothiazine. The presented compounds have been synthesized and analyzed using spectroscopic and spectrometric techniques including FTIR, HRMS, 1H

Synthesis and characterizations of highly luminescent 5-isopropoxybenzo[rst]pentaphene

• Islam S. Marae,
• Jingyun Tan,
• Rengo Yoshioka,
• Zakaria Ziadi,
• Eugene Khaskin,
• Serhii Vasylevskyi,
• Ryota Kabe,
• Xiushang Xu and
• Akimitsu Narita

Beilstein J. Org. Chem. 2025, 21, 270–276, doi:10.3762/bjoc.21.19

• ferric chloride (FeCl3) gave BPP-dione 4 in 70% yield. The chemical structures of BPP-OiPr 3 and BPP-dione 4 were characterized by 1H and 13C NMR spectroscopy as well as mass spectrometry (see Supporting Information File 1, Figures S8–S11). A single crystal of BPP-OiPr 3 suitable for X-ray diffraction

Synthesis of the 1,5-disubstituted tetrazole-methanesulfonylindole hybrid system via high-order multicomponent reaction

• Cesia M. Aguilar-Morales,
• América A. Frías-López,
• Nadia V. Emilio-Velázquez,
• Alejandro Islas-Jácome,
• Angelica Judith Granados-López,
• Jorge Gustavo Araujo-Huitrado,
• Yamilé López-Hernández,
• Hiram Hernández-López,
• Luis Chacón-García,
• Jesús Adrián López and
• Carlos J. Cortés-García

Beilstein J. Org. Chem. 2024, 20, 3077–3084, doi:10.3762/bjoc.20.256

• and resource optimization. In addition, all the target compounds were fully characterized using 1H and 13C NMR spectroscopy and HRMS. It is important to mention that this protocol cannot be considered a true one-pot synthesis, as it requires a solvent exchange between reaction steps (e.g., from

Tandem diazotization/cyclization approach for the synthesis of a fused 1,2,3-triazinone-furazan/furoxan heterocyclic system

• Yuri A. Sidunets,
• Valeriya G. Melekhina and
• Leonid L. Fershtat

Beilstein J. Org. Chem. 2024, 20, 2342–2348, doi:10.3762/bjoc.20.200

• , indicating that the developed tandem protocol does not depend on the presence of the N-oxide moiety in the parent heterocycle. All synthesized triazinones 1 and 7 were fully characterized by IR, 1H and 13C NMR spectroscopy, and high-resolution mass spectrometry. The structure of compounds 1b and 7h was

Novel truxene-based dipyrromethanes (DPMs): synthesis, spectroscopic characterization and photophysical properties

• Shakeel Alvi and
• Rashid Ali

Beilstein J. Org. Chem. 2024, 20, 2163–2170, doi:10.3762/bjoc.20.186

• derivatives were successfully characterized and their structures were established by means of the 1H and 13C NMR spectroscopy, besides further confirmation by mass spectrometry (see Supporting Information File 1). The UV–vis absorption, emission and time-resolved fluorescence spectra Emission and absorption

Synthesis of photo- and ionochromic N-acylated 2-(aminomethylene)benzo[b]thiophene-3(2Н)-ones with a terminal phenanthroline group

• Vladimir P. Rybalkin,
• Sofiya Yu. Zmeeva,
• Lidiya L. Popova,
• Irina V. Dubonosova,
• Olga Yu. Karlutova,
• Oleg P. Demidov,
• Alexander D. Dubonosov and
• Vladimir A. Bren

Beilstein J. Org. Chem. 2024, 20, 552–560, doi:10.3762/bjoc.20.47

• were isolated preparatively and fully characterized by IR, 1H, and 13C NMR spectroscopy as well as HRMS and XRD methods. The reverse thermal reaction was catalyzed by protonic acids. N-Acylated compounds exclusively with Fe2+ formed nonfluorescent complexes with a contrast naked-eye effect: a color

• reaction occurred catalytically in the presence of HClO4. A special technique for the preparative synthesis of photoproducts was developed. For the first time in the course of studying N→O acylotropic migrations, O-acylated photoproducts were comprehensively characterized by IR, 1H and 13C NMR spectroscopy

Cycloaddition reactions of heterocyclic azides with 2-cyanoacetamidines as a new route to C,N-diheteroarylcarbamidines

• Pavel S. Silaichev,
• Tetyana V. Beryozkina,
• Vsevolod V. Melekhin,
• Valeriy O. Filimonov,
• Andrey N. Maslivets,
• Vladimir G. Ilkin,
• Wim Dehaen and
• Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2024, 20, 17–24, doi:10.3762/bjoc.20.3

• effect on the yield of the final compounds 3 observed. The structures of compounds 3a–u were confirmed by IR, 1H and 13C NMR spectroscopy (Figures S1‒S44 in Supporting Information File 1) as well as by high-resolution mass spectrometry (HRMS). X-ray data obtained for compound 3g gave us final proof of

Aldiminium and 1,2,3-triazolium dithiocarboxylate zwitterions derived from cyclic (alkyl)(amino) and mesoionic carbenes

• Nedra Touj,
• François Mazars,
• Guillermo Zaragoza and
• Lionel Delaude

Beilstein J. Org. Chem. 2023, 19, 1947–1956, doi:10.3762/bjoc.19.145

• carbenes with a strong base, followed by their nucleophilic addition onto carbon disulfide. The nine products obtained were characterized by 1H and 13C NMR spectroscopy, FTIR spectroscopy, HR–ESI mass spectrometry, and elemental analysis. Moreover, the molecular structures of two CAAC·CS2 and two MIC·CS2

Consecutive four-component synthesis of trisubstituted 3-iodoindoles by an alkynylation–cyclization–iodination–alkylation sequence

• Nadia Ledermann,
• Alae-Eddine Moubsit and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2023, 19, 1379–1385, doi:10.3762/bjoc.19.99

• compounds 5 in yields between 11–69% after chromatographic workup. The structures of the products were unambiguously confirmed by 1H and 13C NMR spectroscopy, as well as by mass spectrometry. Assuming that four new bonds are being formed in this one-pot process, the range of yield from 11 to 69% (after

• -trisubstitued indoles 8 in good yield (Scheme 4). The 1,2,3-trisubstitued indoles 8 were unambiguously confirmed by 1H and 13C NMR spectroscopy, as well as by mass spectrometry and elemental analysis. Miura et al. could show that 1-alkyl-2,3-diarylindoles constitute a class of blue-emissive indole derivatives

Selective construction of dispiro[indoline-3,2'-quinoline-3',3''-indoline] and dispiro[indoline-3,2'-pyrrole-3',3''-indoline] via three-component reaction

• Ziying Xiao,
• Fengshun Xu,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2023, 19, 1234–1242, doi:10.3762/bjoc.19.91

• structures of the obtained dispiro compounds 3a–m were fully characterized by IR, HRMS, 1H and 13C NMR spectroscopy. Because of the three chiral carbon atoms in the product, several diastereomers might be formed in the reaction. However, TLC monitoring and 1H NMR spectra of the crude products clearly

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

• -diaminopyrazoles 4a–c (Scheme 2). The structures of compounds 4a–c were confirmed by 1H and 13C NMR spectroscopy data, as well as high-resolution mass spectrometry (HRMS). Compound 4a was previously obtained by another method [18]. The spectral characteristics of diaminopyrazole 4a reported in [18] correspond to

• group during the reaction. The structures of compounds 5a–e were confirmed by 1H and 13C NMR spectroscopy and HRMS, as well as X-ray diffraction analysis of a single crystal of compound 5b. The involvement of arylhydrazines 3b,c in the reaction with enamines 2a–d similarly leads to the formation of 1

• upon addition of hydrochloric acid. This is probably due to the protonation of the dimethylamino moiety or/and that dimethylamine hydrochloride is a better leaving group than the free base. The structures of compounds 6a–f were confirmed by 1H and 13C NMR spectroscopy and HRMS, as well as X-ray

Synthesis of imidazo[4,5-e][1,3]thiazino[2,3-c][1,2,4]triazines via a base-induced rearrangement of functionalized imidazo[4,5-e]thiazolo[2,3-c][1,2,4]triazines

• Dmitry B. Vinogradov,
• Alexei N. Izmest’ev,
• Angelina N. Kravchenko,
• Yuri A. Strelenko and
• Galina A. Gazieva

Beilstein J. Org. Chem. 2023, 19, 1047–1054, doi:10.3762/bjoc.19.80

• in the thiazine ring leads to the cleavage of the triazine C–N bond. Further proton transfer gives product 9. The structures of the synthesized compounds 3a,b,j and 5a–k,m were confirmed by IR, 1H and 13C NMR spectroscopy, and high-resolution mass spectrometry. the potassium salts 3c–i,k,m were

Synthesis and electrochemical properties of 3,4,5-tris(chlorophenyl)-1,2-diphosphaferrocenes

• Almaz A. Zagidullin,
• Farida F. Akhmatkhanova,
• Mikhail N. Khrizanforov,
• Robert R. Fayzullin,
• Tatiana P. Gerasimova,
• Ilya A. Bezkishko and
• Vasili A. Miluykov

Beilstein J. Org. Chem. 2022, 18, 1338–1345, doi:10.3762/bjoc.18.139

• confirmed by 31P, 1H, and 13C NMR spectroscopy. The 31P{1H} NMR spectra of phosphonium bromides 6 showed a singlet at about 40 ppm, which is typical for phosphonium salts. The 13C{1H} NMR spectra consisted of a doublet at about 20 ppm, corresponding to the carbon atom C1, which is characteristic for the sp3

• (Scheme 3). The structure of 3,4,5-triaryl-1,2-diphosphaferrocene 8b was confirmed by 31P, 1H, and 13C NMR spectroscopy. The 31P{1H} NMR spectrum of 8b showed a singlet at about −10 ppm, shifted upfield by about 210 ppm in comparison to the starting 1,2-diphospholide anion 7b. In the 1H NMR spectra

Ionic multiresonant thermally activated delayed fluorescence emitters for light emitting electrochemical cells

• Merve Karaman,
• Abhishek Kumar Gupta,
• Subeesh Madayanad Suresh,
• Tomas Matulaitis,
• Lorenzo Mardegan,
• Daniel Tordera,
• Henk J. Bolink,
• Sen Wu,
• Stuart Warriner,
• Ifor D. Samuel and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2022, 18, 1311–1321, doi:10.3762/bjoc.18.136

• synthetic strategy, which itself was synthesized from Br-DiKTa [28] following a Buchwald–Hartwig coupling. Details of the synthesis are found in Supporting Information File 1. The identity and purity of the molecules were verified using a combination of 1H and 13C NMR spectroscopy, high resolution mass

Thermally activated delayed fluorescence (TADF) emitters: sensing and boosting spin-flipping by aggregation

• Ashish Kumar Mazumdar,
• Gyana Prakash Nanda,
• Nisha Yadav,
• Upasana Deori,
• Upasha Acharyya,
• Bahadur Sk and
• Pachaiyappan Rajamalli

Beilstein J. Org. Chem. 2022, 18, 1177–1187, doi:10.3762/bjoc.18.122

• Supporting Information File 1. Both compounds were further purified by temperature-gradient vacuum sublimation and characterized by 1H and 13C NMR spectroscopy (Figures S9–S12, Supporting Information File 1) as well as high-resolution mass spectrometry. Photophysical studies and DFT calculations The UV–vis

Synthesis of N-phenyl- and N-thiazolyl-1H-indazoles by copper-catalyzed intramolecular N-arylation of ortho-chlorinated arylhydrazones

• Yara Cristina Marchioro Barbosa,
• Guilherme Caneppele Paveglio,
• Claudio Martin Pereira de Pereira,
• Sidnei Moura,
• Cristiane Storck Schwalm,
• Gleison Antonio Casagrande and
• Lucas Pizzuti

Beilstein J. Org. Chem. 2022, 18, 1079–1087, doi:10.3762/bjoc.18.110

• . All products were fully characterized by HRMS as well as 1H and 13C NMR spectroscopy. Thus, this approach is valuable for promoting the synthesis of N-phenyl-1H-indazoles in a higher yield than that reported in the literature using copper catalysis and the same substrates. This study also prompted the

• conditions for the synthesis of 1-phenyl-1H-indazole (2a).a Selected experimental data for the synthesis of N-phenyl-1H-indazoles 2a,b,d–h. Selected experimental data for the synthesis of N-thiazolyl-1H-indazoles 4a,d–h. Supporting Information Supporting Information File 88: Reaction analysis by 1H and 13C

• NMR spectroscopy, characterization data, NMR spectra for the 1H-indazoles and HRMS spectra for the arylhydrazones and 1H-indazoles. Acknowledgements The authors thank Prof. Lívia Streit, Federal University of Rio Grande do Sul, for the language corrections. Funding The authors acknowledge Coordenação

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

• substituent and an N-alkyl group (considering that N-aryl nitrophenyl-substituted compound 10o was obtained in a respectable 91% yield). The structures of compounds 10a–s were unequivocally confirmed by 1H and 13C NMR spectroscopy (paying a particular attention to the appearance of the C=N2 signal in the

• ). Using more reactive (electron-rich) arenes results in lower diastereoselectivity and regiospecificity of the reaction (cf. 9q, 9v, and 9w). The structure and the initially anticipated trans-configuration of the products 9 was unequivocally confirmed by 1H and 13C NMR spectroscopy as well as, in the case

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

• compound, 10-imino-2-methylpyrido[1,2-a]pyrrolo[3,4-d]pyrimidine-1,3(2H,10H)-dione (3a), in 97% yield. The chemical structure of product 3a was confirmed by 1H and 13C NMR spectroscopy (Figures S1 and S2 in Supporting Information File 1) and was obtained via the following reaction mechanism: nucleophilic

• 13C NMR spectroscopy (Figures S5 and S6 in Supporting Information File 1). Similarly, the reaction of 1 with 2-aminopyridine derivatives 2d–g bearing electron-withdrawing groups, except for the nitro-group containing substrate 2h, at position 5 of the pyridine ring, afforded N-methyl-4-((pyridin-2-yl

• containing two acceptor (maleimide and pyridine) and one donor (secondary amine) moieties in 72% yield (Scheme 1). Due to the electron-withdrawing effect of the bromo substituent at position 5 of the pyridine ring, the cyclization reaction did not occur. The structure of product 4a was confirmed by 1H and

Synthesis of a new water-soluble hexacarboxylated tribenzotriquinacene derivative and its competitive host–guest interaction for drug delivery

• Man-Ping Li,
• Nan Yang and
• Wen-Rong Xu

Beilstein J. Org. Chem. 2022, 18, 539–548, doi:10.3762/bjoc.18.56

• synthesized compounds were fully characterized by 1H and 13C NMR spectroscopy and mass spectrometry (see Supporting Information File 1) and the data were found to be consistent with the proposed structures. Host–guest complexation of TBTQ-CB6 with dimethyl viologen (MV). The host–guest complexation between

Substituent effect on TADF properties of 2-modified 4,6-bis(3,6-di-tert-butyl-9-carbazolyl)-5-methylpyrimidines

• Irina Fiodorova,
• Tomas Serevičius,
• Rokas Skaisgiris,
• Saulius Juršėnas and
• Sigitas Tumkevicius

Beilstein J. Org. Chem. 2022, 18, 497–507, doi:10.3762/bjoc.18.52

• the formation of the 2-cyano- and 2-(4-tert-butylphenylthio) derivatives 4 and 5 in 65% and 77% yield, respectively. Finally, compound 5 in the reaction with oxone furnished 2-(4-tert-butylphenylsulfonyl) derivative 6 in reasonable 68% yield. 1H and 13C NMR spectroscopy and HRMS were employed to

Anomeric 1,2,3-triazole-linked sialic acid derivatives show selective inhibition towards a bacterial neuraminidase over a trypanosome trans-sialidase

• Peterson de Andrade,
• Sanaz Ahmadipour and
• Robert A. Field

Beilstein J. Org. Chem. 2022, 18, 208–216, doi:10.3762/bjoc.18.24

• structure of compounds 2a–h were confirmed by 1H and 13C NMR spectroscopy (see spectra in Supporting Information File 1) as well as HRESIMS analyses. The triazole ring hydrogen was observed as a singlet in the range δH 7.7–8.5 ppm and its corresponding carbon (CH-triazole) in the range δC 120–123 ppm

A two-phase bromination process using tetraalkylammonium hydroxide for the practical synthesis of α-bromolactones from lactones

• Yuki Yamamoto,
• Akihiro Tabuchi,
• Kazumi Hosono,
• Takanori Ochi,
• Kento Yamazaki,
• Shintaro Kodama,
• Akihiro Nomoto and
• Akiya Ogawa

Beilstein J. Org. Chem. 2021, 17, 2906–2914, doi:10.3762/bjoc.17.198

• remove excess amount of Br2 and the formed HBr (under open-air) then filtered. The filtrate was concentrated under reduced pressure to produce 2,5-dibromopentanoic acid 2a in 90% yield with trace amount of 1a. The purity of 2a was determined by 1H and 13C NMR spectroscopy, and 2a was used for the

A novel methodology for the efficient synthesis of 3-monohalooxindoles by acidolysis of 3-phosphate-substituted oxindoles with haloid acids

• Li Liu,
• Yue Li,
• Tiao Huang,
• Dulin Kong and
• Mingshu Wu

Beilstein J. Org. Chem. 2021, 17, 2321–2328, doi:10.3762/bjoc.17.150

• chromatography separation is not usually required. This outcome indicated that the transformation could be applicable for larger-scale syntheses of 3-monohalooxindoles products. In addition, the structure of all products 3 and 4 was unambiguously assigned by 1H and 13C NMR spectroscopy and HRMS. Especially the

Annulation of a 1,3-dithiole ring to a sterically hindered o-quinone core. Novel ditopic redox-active ligands

• Sergey V. Norkov,
• Anton V. Cherkasov,
• Andrey S. Shavyrin,
• Maxim V. Arsenyev,
• Viacheslav A. Kuropatov and
• Vladimir K. Cherkasov

Beilstein J. Org. Chem. 2021, 17, 273–282, doi:10.3762/bjoc.17.26

• -quinone 4. Each o-quinone molecule bridges two adjacent sodium ions. The bond lengths distribution in the o-quinone moiety in 8 is typical of sterically hindered o-quinones (Table S1 in Supporting Information File 1). According to 1H and 13C NMR spectroscopy data, adduct 8 in CD3OD solution exists as

Ultrasound-assisted Strecker synthesis of novel 2-(hetero)aryl-2-(arylamino)acetonitrile derivatives

• Emese Gal,
• Luiza Gaina,
• Hermina Petkes,
• Alexandra Pop,
• Castelia Cristea,
• Gabriel Barta,
• Dan Cristian Vodnar and
• Luminiţa Silaghi-Dumitrescu

Beilstein J. Org. Chem. 2020, 16, 2929–2936, doi:10.3762/bjoc.16.242

• confirmed the molecular weight of the new compounds, while high-resolution 1H and 13C NMR spectroscopy afforded the complete characterization of the molecular skeleton. In the 1H NMR spectra of compounds 2c, 2e–l a vicinal coupling constant between the protons in the >CH–NH– unit (3J ≈ 7.5–8.7 Hz) was