Synthesis, structure, ionochromic and cytotoxic properties of new 2-(indolin-2-yl)-1,3-tropolones

• Yurii A. Sayapin,
• Eugeny A. Gusakov,
• Inna O. Tupaeva,
• Alexander D. Dubonosov,
• Igor V. Dorogan,
• Valery V. Tkachev,
• Anna S. Goncharova,
• Gennady V. Shilov,
• Natalia S. Kuznetsova,
• Svetlana Y. Filippova,
• Tatyana A. Krasnikova,
• Yanis A. Boumber,
• Alexey Y. Maksimov,
• Sergey M. Aldoshin and
• Vladimir I. Minkin

Beilstein J. Org. Chem. 2025, 21, 358–368, doi:10.3762/bjoc.21.26

• represent molecular switches of optical and fluorescent properties under sequential addition of CN− and Hg2+ ions and the transformation cycle presented in Scheme 3 can be repeated at least 5–6 times. The resulting compounds 7b and 8a,b have extremely low water solubility, which makes it impossible to

• properties under sequential addition of CN− and Hg2+ ions. 2-(1,1-Dimethyl-1H-benzo[e]indolin-2-yl)-5,6,7-trichloro-1,3-tropolone (7a) was found to exhibit high in vitro cytotoxic activity against A431 skin cancer and H1299 lung cancer cell lines. In addition, the IC50 values of compound 7a are significantly

Recent advances in electrochemical copper catalysis for modern organic synthesis

• Yemin Kim and
• Won Jun Jang

Beilstein J. Org. Chem. 2025, 21, 155–178, doi:10.3762/bjoc.21.9

• (Figure 15) [70]. In this catalytic system, catalytic amounts of Cu(sBOX) (L3) and Co(salen) complexes promote the formation of chiral nitriles 89 in the presence of PhSiH3 (88) as the hydride source and TMSCN (21) as the cyanide source via the effective sequential addition of a hydrogen atom and a CN

Advances in radical peroxidation with hydroperoxides

• Oleg V. Bityukov,
• Pavel Yu. Serdyuchenko,
• Andrey S. Kirillov,
• Gennady I. Nikishin,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2024, 20, 2959–3006, doi:10.3762/bjoc.20.249

• and tert-butylperoxy moiety (Scheme 33) [89]. The mechanism of the process is probably based on the formation of radical species A and B, which disproportionate to form the intermediate C. Sequential addition of sulfonyl and tert-butylperoxy radicals to the double bond of intermediate C leads to

Investigation of a bimetallic terbium(III)/copper(II) chemosensor for the detection of aqueous hydrogen sulfide

• Parvathy Mini,
• Michael R. Grace,
• Genevieve H. Dennison and
• Kellie L. Tuck

Beilstein J. Org. Chem. 2024, 20, 2818–2826, doi:10.3762/bjoc.20.237

• an antenna chromophore and a receptor for Cu2+ ions; the Cu2+ complex was shown to be a chemosensor for the detection of aqueous hydrogen sulfide. The chemosensor exhibited significant reversibility over multiple cycles, observed with the sequential addition of Na2S followed by Cu2+ ions. The limit

Efficacy of radical reactions of isocyanides with heteroatom radicals in organic synthesis

• Akiya Ogawa and
• Yuki Yamamoto

Beilstein J. Org. Chem. 2024, 20, 2114–2128, doi:10.3762/bjoc.20.182

• yields the sequential addition products 9 in moderate to excellent yields (Scheme 5) [33]. The product can be used as a precursor for the carbapenem scaffold, one of the basic scaffolds of antibiotics. Thermal or photoirradiated decomposition of organotellurium compounds generates carbon radicals that

• thioselenation and catalytic dithiolation of isocyanides. Synthesis of carbacephem framework. Sequential addition of (PhSe)2 to ethyl propiolate and isocyanide. Isocyanide insertion reaction into carbon-tellurium bonds. Radical addition to isocyanides with disubstituted phosphines. Radical addition to phenyl

Rapid construction of tricyclic tetrahydrocyclopenta[4,5]pyrrolo[2,3-b]pyridine via isocyanide-based multicomponent reaction

• Xiu-Yu Chen,
• Ying Han,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2024, 20, 1436–1443, doi:10.3762/bjoc.20.126

• polycyclic compounds. At first, the nucleophilic addition of alkyl isocyanide to dialkyl but-2-ynedioate afforded the expected Huisgen’s 1,4-dipolar intermediate A. Secondly, the sequential addition of the Huisgen’s 1,4-dipole A to the second molecular dialkyl but-2-ynedioate resulted in a 1,5-dipolar

Domino reactions of chromones with activated carbonyl compounds

• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 1256–1269, doi:10.3762/bjoc.20.108

• ][11][12]. For example, 2 can be transformed to its dianion 7 by action of two equivalents of LDA or by sequential addition of sodium hydride and n-butyllithium (Scheme 1). In contrast to 2, dianion 7 reacts with electrophiles at its terminal carbon atom. 1,3-Bis(silyloxy)-1,3-butadienes, containing

Synthesis and characterization of water-soluble C₆₀–peptide conjugates

• Yue Ma,
• Lorenzo Persi and
• Yoko Yamakoshi

Beilstein J. Org. Chem. 2024, 20, 777–786, doi:10.3762/bjoc.20.71

• derivatives by covalently attaching water-soluble moieties to the fullerene core. Subsequently, Nakamura and co-workers further developed reactions between C60 and organocopper reagents, enabling the sequential addition of functional groups to obtain penta- and decaadducts, which largely enhanced the water

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

• light and H+ or sequential addition of Fe2+ and AcO− ions. Keywords: fluorescence; molecular switches; N→O acyl rearrangement; naked eye effect; photochromism; Introduction Photochromism is defined as the reversible transformation of a molecular entity between different forms, having different

• sequential addition of Fe2+ and AcO−, we synthesized N-acylated 2-(aminomethylene)benzo[b]thiophene-3(2Н)-ones with a terminal phenanthroline substituent and studied the spectral-luminescent, photochromic and ionochromic properties. The phenanthroline moiety was incorporated into the molecule due to the

• sequential addition of Fe2+ and AcO−. Experimental General The 1H and 13C NMR spectra were recorded on an integrated analytical LC–SPE–NMR–MS system AVANCE-600 (Bruker, 600 MHz for 1H and 150.96 MHz for 13C) in CDCl3. The signals were referred to with respect to the signals of residual protons of deuterated

Iron-catalyzed domino coupling reactions of π-systems

• Austin Pounder and
• William Tam

Beilstein J. Org. Chem. 2021, 17, 2848–2893, doi:10.3762/bjoc.17.196

Selective sulfonylation and isonitrilation of para-quinone methides employing TosMIC as a source of sulfonyl group or isonitrile group

• Chuanhua Qu,
• Run Huang,
• Yong Li,
• Tong Liu,
• Yuan Chen and
• Guiting Song

Beilstein J. Org. Chem. 2021, 17, 2822–2831, doi:10.3762/bjoc.17.193

• is exemplified in Scheme 6C. The sulfonylation reaction starts with ZnI2/base system mediated C–S-bond cleavage of TosMIC derivative 2c to yield Ts anion II, in which 2c acts as the sulfonyl source. Finally, the sulfonylated diarylmethane 3a is formed by a sequential addition/aromatization process

Recent advances in the syntheses of anthracene derivatives

• Giovanni S. Baviera and
• Paulo M. Donate

Beilstein J. Org. Chem. 2021, 17, 2028–2050, doi:10.3762/bjoc.17.131

• brominated naphthalene 153 with PhLi yielded compound 154, which collapsed to naphthotriyne 155 at elevated temperatures. Sequential addition of furan generated the trisadduct 156. Then, dibenz[a,c]anthracene 158 was obtained in good yield (86%) in two steps by hydrogenation of 156 and further dehydration of

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

Synthetic accesses to biguanide compounds

• Oleksandr Grytsai,
• Cyril Ronco and
• Rachid Benhida

Beilstein J. Org. Chem. 2021, 17, 1001–1040, doi:10.3762/bjoc.17.82

• biguanides by the sequential addition of various primary and secondary aliphatic and aromatic amines to sodium dicyanamide in acidic aqueous alcohol mixtures (Scheme 24). The first addition on the sodium dicyanamide occurred in variable yields depending on the structure of the amine with lower reactivities

Microwave-assisted multicomponent reactions in heterocyclic chemistry and mechanistic aspects

• Shivani Gulati,
• Stephy Elza John and
• Nagula Shankaraiah

Beilstein J. Org. Chem. 2021, 17, 819–865, doi:10.3762/bjoc.17.71

• of MWA-MCR in the construction of fused polycycles with functional diversity for the generation of a library of pharmacologically active molecules. The construction of fused annulated rings are seldomly reported often achieved by a sequential addition approach [40]. Contributing to the same and

Et₃N/DMSO-supported one-pot synthesis of highly fluorescent β-carboline-linked benzothiophenones via sulfur insertion and estimation of the photophysical properties

• Dharmender Singh,
• Vipin Kumar and
• Virender Singh

Beilstein J. Org. Chem. 2020, 16, 1740–1753, doi:10.3762/bjoc.16.146

• of the targeted products was attempted. Therefore, after the formation of the 2-nitrochalcone 1bA, excess of MeOH was decanted, and the crude product was redissolved in 1 mL of DMSO followed by the sequential addition of Et3N (5 equiv) and elemental sulfur (5 equiv). To our pleasure, the reaction at

• the sequential addition of sulfur powder (0.089 g, 2.80 mmol) and Et3N (0.390 mL, 2.80 mmol) at room temperature. The reaction mixture was stirred at 70 °C for 20 min. After completion of the reaction (as analyzed by TLC), the product 2bA was directly purified through column chromatography on silica

Azidophosphonium salt-directed chemoselective synthesis of (E)/(Z)-cinnamyl-1H-triazoles and regiospecific access to bromomethylcoumarins from Morita–Baylis–Hillman adducts

• Soundararajan Karthikeyan,
• Radha Krishnan Shobana,
• Kamarajapurathu Raju Subimol,
• J. Helen Ratna Monica and
• Ayyanoth Karthik Krishna Kumar

Beilstein J. Org. Chem. 2020, 16, 1579–1587, doi:10.3762/bjoc.16.130

• -triazoles Va (Figure 1). At this stage, we sought to analyse the outcome of the proposed reaction following a sequential addition of the reagents utilised for the synthesis of AzPS. Therefore, a preliminary investigation was attempted using the MBH adduct 1a (1 equiv) and propargyl alcohol (2a,1.2 equiv) in

Heterogeneous photocatalysis in flow chemical reactors

• Christopher G. Thomson,
• Ai-Lan Lee and
• Filipe Vilela

Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125

Sequential Ugi reaction/base-induced ring closing/IAAC protocol toward triazolobenzodiazepine-fused diketopiperazines and hydantoins

• Robby Vroemans,
• Fante Bamba,
• Jonas Winters,
• Joice Thomas,
• Jeroen Jacobs,
• Luc Van Meervelt,
• Jubi John and
• Wim Dehaen

Beilstein J. Org. Chem. 2018, 14, 626–633, doi:10.3762/bjoc.14.49

• -azidobenzaldehyde (1a), propargylamine (2a), 2-chloroacetic acid (3a) and benzyl isocyanide (4a, Scheme 2). Initially, the condensation of the aldehyde and the amine was effected in MeOH in the presence of 4 Å MS. This was followed by the sequential addition of chloroacetic acid and the isocyanide which, after 24

Gram-scale preparation of negative-type liquid crystals with a CF₂CF₂-carbocycle unit via an improved short-step synthetic protocol

• Tatsuya Kumon,
• Shohei Hashishita,
• Takumi Kida,
• Shigeyuki Yamada,
• Takashi Ishihara and
• Tsutomu Konno

Beilstein J. Org. Chem. 2018, 14, 148–154, doi:10.3762/bjoc.14.10

• -step manipulations for obtaining the CF2CF2-containing multicyclic molecules 1 and 2. Scope and limitation The synthetic route was initiated by the sequential addition–elimination reaction of 4-n-propylphenylmagnesium bromide (4-n-PrC6H4MgBr) with commercially available dimethyl tetrafluorosuccinate (7

The chemistry and biology of mycolactones

• Matthias Gehringer and
• Karl-Heinz Altmann

Beilstein J. Org. Chem. 2017, 13, 1596–1660, doi:10.3762/bjoc.13.159

Copper-catalyzed asymmetric conjugate addition of organometallic reagents to extended Michael acceptors

• Thibault E. Schmid,
• Sammy Drissi-Amraoui,
• Christophe Crévisy,
• Olivier Baslé and
• Marc Mauduit

Beilstein J. Org. Chem. 2015, 11, 2418–2434, doi:10.3762/bjoc.11.263

• ; sequential addition; Introduction Amongst the variety of synthetic methods available for the formation of C–C or C–heteroatom bonds, the asymmetric conjugate addition (ACA) of nucleophiles to electron-deficient alkenes is one of the most relevant and versatile for the synthesis of complex chiral molecules

Synthesis and evaluation of the biostability and cell compatibility of novel conjugates of nucleobase, peptidic epitope, and saccharide

• Dan Yuan,
• Xuewen Du,
• Junfeng Shi,
• Ning Zhou,
• Abdulgader Ahmed Baoum,
• Khalid Omar Al Footy,
• Khadija Omar Badahdah and
• Bing Xu

Beilstein J. Org. Chem. 2015, 11, 1352–1359, doi:10.3762/bjoc.11.145

• repeating the removal of the Fmoc group and sequential addition of Fmoc-Thr(t-Bu)-OH, Fmoc-Thr(t-Bu)-OH and thymine-1-acetic acid. For the final step of the SPPS, we used 2,2,2-trifluoroethanol/dichloromethane (TFE/DCM 2:8) to cleave the fully protected NA from the resin. For conjugates 5–8, we cleaved the

Chiroptical properties of 1,3-diphenylallene-anchored tetrathiafulvalene and its polymer synthesis

• Masashi Hasegawa,
• Junta Endo,
• Seiya Iwata,
• Toshiaki Shimasaki and
• Yasuhiro Mazaki

Beilstein J. Org. Chem. 2015, 11, 972–979, doi:10.3762/bjoc.11.109

• structures of 3 in various redox states, cationic species of 32+ and 34+ were prepared by their reaction with an adequate amount of Fe(ClO4)3, as the oxidant, in a MeCN/CH2Cl2 (v/v = 1:4) solution (Figure 5a). During the sequential addition of between 0 to 2 equivalents of the oxidant, no isosbestic point

• species of PTDPA were also produced by the sequential addition of Fe(ClO4)3 (Figure 5b). During the oxidation, three phases of PTDPA-(0), PTDPA-(+1), and PTDPA-(+2), corresponding to the oxidation stages involving TTF, TTF•+, and TTF2+, respectively, were observed during the oxidation. The spectrum of the

Synthesis of the furo[2,3-b]chromene ring system of hyperaspindols A and B

• Danielle L. Paterson and
• David Barker

Beilstein J. Org. Chem. 2015, 11, 265–270, doi:10.3762/bjoc.11.29

• methylenedioxyphenyl groups in ketone 8 would be added by sequential addition of aryllithiates to both the carbonyl and aldehyde groups, derived from the terminal alkene, of a homoallylic carboxylic acid derivative 9. Our route to ketone 8 began from salicylaldehyde (10) which underwent a Horner–Wadsworth–Emmons