C2 to C6 biobased carbonyl platforms for fine chemistry

• Jingjing Jiang,
• Muhammad Noman Haider Tariq,
• Florence Popowycz,
• Yanlong Gu and
• Yves Queneau

Beilstein J. Org. Chem. 2025, 21, 2103–2172, doi:10.3762/bjoc.21.165

Further elaboration of the stereodivergent approach to chaetominine-type alkaloids: synthesis of the reported structures of aspera chaetominines A and B and revised structure of aspera chaetominine B

• Jin-Fang Lü,
• Jiang-Feng Wu,
• Jian-Liang Ye and
• Pei-Qiang Huang

Beilstein J. Org. Chem. 2025, 21, 2072–2081, doi:10.3762/bjoc.21.162

• 1H and 13C NMR are methanol-d4 that is different from Tan’s work [21] who used DMSO-d6 to record 1H and 13C NMR spectra of (–)-chaetominine (1). Thus we undertook the synthesis of the proposed structures of aspera chaetominines A (12) and B (13). By adopting our first-generation strategy [57][58][61

• incorrect. It is worth noting that compound 12 has been obtained in our previous investigation [65]. However, the 1H and 13C NMR spectra were recorded in DMSO-d6 which prevent a direct comparison with the data of aspera chaetominine A. We next addressed the synthesis of aspera chaetominine B (13). Employing

• (–)-isochaetominine C (6), whose absolute configuration is tentatively assigned as 2R,3R,11S,14R. It is worth noting that compound 13 has been obtained in our previous investigation [63]. However, the 1H and 13C NMR spectra were recorded in DMSO-d6 which prevent a direct comparison with the data of aspera

Switchable pathways of multicomponent heterocyclizations of 5-amino-1,2,4-triazoles with salicylaldehydes and pyruvic acid

• Yana I. Sakhno,
• Oleksander V. Buravov,
• Kostyantyn Yu. Yurkov,
• Anastasia Yu. Andryushchenko,
• Svitlana V. Shishkina and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2025, 21, 2030–2035, doi:10.3762/bjoc.21.158

• substituents. The peaks of the proton of the carboxyl group is not recognized, probably due to exchange processes. The signals of the CH2 group in the range around δ = 2.5 ppm are not always clearly identifiable, as they partially or completely overlap with the remaining DMSO signal. Compounds 4g–j are

Synthesis, biological and electrochemical evaluation of glycidyl esters of phosphorus acids as potential anticancer drugs

• Almaz A. Zagidullin,
• Emil R. Bulatov,
• Mikhail N. Khrizanforov,
• Damir R. Davletshin,
• Elvina M. Gilyazova,
• Ivan A. Strelkov and
• Vasily A. Miluykov

Beilstein J. Org. Chem. 2025, 21, 1909–1916, doi:10.3762/bjoc.21.148

• a final concentration of 0.5 mg/mL. Plates were incubated for 3 hours at 37 °C in a CO2 incubator to allow for formazan crystal formation. Subsequently, 150 μL of dimethyl sulfoxide (DMSO) was added to each well to solubilize the formazan. Plates were shaken for 15 minutes, and absorbance was

Systematic pore lipophilization to enhance the efficiency of an amine-based MOF catalyst in the solvent-free Knoevenagel reaction

• Pricilla Matseketsa,
• Margret Kumbirayi Ruwimbo Pagare and
• Tendai Gadzikwa

Beilstein J. Org. Chem. 2025, 21, 1854–1863, doi:10.3762/bjoc.21.144

• of the MOF product digested in D2SO4/DMSO-d6 (Figure 2B). Conversions were estimated by selecting the “same” proton in the starting material and in the products and integrating the corresponding peaks and setting the total to 100% (see Supporting Information File 1). We observed that the reactions

• -synthesis modification (PSM). A) Schematic representation of the reaction of KSU-1 with aliphatic isocyanates and the estimated conversions at –OH and –NH2. B) The corresponding 1H NMR spectra of the MOF reaction products digested in a solution of D2SO4 in DMSO-d6. A) Schematic representation of the

Photoswitches beyond azobenzene: a beginner’s guide

• Michela Marcon,
• Christoph Haag and
• Burkhard König

Beilstein J. Org. Chem. 2025, 21, 1808–1853, doi:10.3762/bjoc.21.143

• , however, it leads to a poor Z–E PSS and poor resistance to fatigue. This is most likely due to internal relaxation processes prevailing over photoswitching. One interesting finding was the strong dependency of the thermal half-life on concentration in DMSO. The authors hypothesised the aggregation of 109

Fe-catalyzed efficient synthesis of 2,4- and 4-substituted quinolines via C(sp²)–C(sp²) bond scission of styrenes

• Prafull A. Jagtap,
• Manish M. Petkar,
• Vaishnavi R. Sawant and
• Bhalchandra M. Bhanage

Beilstein J. Org. Chem. 2025, 21, 1799–1807, doi:10.3762/bjoc.21.142

• employed an I2/DMSO-facilitated C–C bond-scission strategy of styrenes, followed by C–N bond formation and subsequent [4 + 2] annulation. Jiang and co-workers developed a method for synthesizing 4-substituted quinolines using vinyl azides as dual synthons, facilitating both the C–C and C–N bond cleavage

pH-Controlled isomerization kinetics of ortho-disubstituted benzamidines: E/Z isomerism and axial chirality

• Ryota Kimura,
• Satoshi Ichikawa and
• Akira Katsuyama

Beilstein J. Org. Chem. 2025, 21, 1568–1576, doi:10.3762/bjoc.21.120

• bond rotation was investigated by variable temperature nuclear magnetic resonance (VT-NMR) spectra (Figure 3) in DMSO-d6 [27]. In the case of the molecular form of amidine 1 (Figure 3a), the signals corresponding to the two methyl groups resulting from the amidine E/Z isomerism were observed separately

• protonated form calculated by the DFT method. Comparison of VT-NMR spectra of a) amidine 1 and b) its trifluoroacetate salt 1-H+ in DMSO-d6 (400 MHz). Separation and isolation of amidine E/Z isomers by RP-HPLC. The mobile phase contained CF3CO2H to protonate the amidine moiety. Kinetic analysis of the

Synthesis of an aza[5]helicene-incorporated macrocyclic heteroarene via oxidation of an o-phenylene-pyrrole-thiophene icosamer

• Yusuke Matsuo,
• Aoi Nakagawa,
• Shu Seki and
• Takayuki Tanaka

Beilstein J. Org. Chem. 2025, 21, 1561–1567, doi:10.3762/bjoc.21.119

• and evaporation of the solvent to afford a crude product, which was recrystallized from THF to give 5 in 58% yield. Due to its poor solubility in common organic solvents, the 1H NMR spectrum could only be recorded in DMSO. At room temperature, the 1H NMR spectrum in DMSO-d6 exhibited broad signals in

• -phenylene and aza[5]helicene segments, and between the o-phenylene and thiophene segments, were 37.52° and 44.28°, respectively. Four NH sites of the aza[5]helicene moiety formed hydrogen bonds with DMSO molecules in the crystal lattice, as observed in aza[n]helicenes recently reported [28], while the other

• emission spectra of 4 were measured in DMSO (Figure 5a). As observed for other o-phenylene-bridged cyclic heteroarenes in previous reports, compound 4 exhibited a broad featureless absorption band up to 450 nm, with emission peaked at 546 nm. The red-shifted emission is likely due to a significant

Facile synthesis of hydantoin/1,2,4-oxadiazoline spiro-compounds via 1,3-dipolar cycloaddition of nitrile oxides to 5-iminohydantoins

• Juliana V. Petrova,
• Varvara T. Tkachenko,
• Victor A. Tafeenko,
• Anna S. Pestretsova,
• Vadim S. Pokrovsky,
• Maxim E. Kukushkin and
• Elena K. Beloglazkina

Beilstein J. Org. Chem. 2025, 21, 1552–1560, doi:10.3762/bjoc.21.118

• compounds in two-fold serial (50–100 μM) dilutions. Only DMSO + PBS (phosphate-buffered saline) was used as a control, since the studied compounds were soluble only in DMSO. Cell viability was measured using the standard MTT test [42]. Absorbance was measured at 540 nm using a Multiskan™ FC microplate

Azide–alkyne cycloaddition (click) reaction in biomass-derived solvent Cyrene^TM under one-pot conditions

• Zoltán Medgyesi and
• László T. Mika

Beilstein J. Org. Chem. 2025, 21, 1544–1551, doi:10.3762/bjoc.21.117

• used for click reactions such as chlorinated hydrocarbons [15][16], toluene [16], tetrahydrofuran (THF) [17][18], N,N-dimethylformamide (DMF) [19][20], N-methylpyrrolidone (NMP) [21], dimethyl sulfoxide (DMSO) [17][19][22], or acetonitrile [23] are classified into Class 1 and 2, of which applications

• -dioxane) or low (DMF, NMP, DMSO) (Figure 1). While low conversion was still detected in biomass-originated 2-MeTHF, MeLev, and EtLev established better performance. When their corresponding 4-alkoxy derivatives were applied, moderate (Me-4MeOV) or slightly lower (Et-4EtOV) conversions could be observed

• is lower than that obtained in the conventional organic medium DMSO (E-factor = 104, [46]) and higher than the one calculated by Citarella (E-factor = 24, [39]) for the CyreneTM-based protocol. However, they used a 15 times higher substrate loading. Conclusion In conclusion, we have demonstrated that

General method for the synthesis of enaminones via photocatalysis

• Paula Pérez-Ramos,
• Raquel G. Soengas and
• Humberto Rodríguez-Solla

Beilstein J. Org. Chem. 2025, 21, 1535–1543, doi:10.3762/bjoc.21.116

• by DME, DMSO or acetone diminished the product yields (Table 1, entries 7–9). The reactivity of acridinium PC1 was superior to that of other photocatalysts, including 4-CzlPN (PC2) and [Ir(dF(CF3)ppy)2(dtbbpy)]PF6 (PC3) (Table 1, entries 10 and 11). Attempts to increase the temperature of the process

Advances in nitrogen-containing helicenes: synthesis, chiroptical properties, and optoelectronic applications

• Meng Qiu,
• Jing Du,
• Nai-Te Yao,
• Xin-Yue Wang and
• Han-Yuan Gong

Beilstein J. Org. Chem. 2025, 21, 1422–1453, doi:10.3762/bjoc.21.106

• large Stokes shift (85 nm) with emission at 530 nm in DMSO [23] (Table 2). Collectively, these studies underscore the structural versatility and functional tunability of heterohelicenes, establishing them as robust platforms for advanced chiral optoelectronic materials. Their diverse response to

• . However, compound 34c stands out due to its pronounced solvatofluorochromism (λem = 546 nm, ΦF = 0.42 in DMSO). Among the series, compound 34b exhibits the highest |glum| of 7.22 × 10−3, while compound 34c shows the greatest BCPL as 29.3 M−1 cm−1. These studies underscore the importance of regioisomerism

Tautomerism and switching in 7-hydroxy-8-(azophenyl)quinoline and similar compounds

• Lidia Zaharieva,
• Vera Deneva,
• Fadhil S. Kamounah,
• Nikolay Vassilev,
• Ivan Angelov,
• Michael Pittelkow and
• Liudmil Antonov

Beilstein J. Org. Chem. 2025, 21, 1404–1421, doi:10.3762/bjoc.21.105

• =O group of the keto tautomers [51][56]). The effects of acetone, methanol and DMSO, as seen, are based only on the increased (comparing to toluene) dielectric constant of the solvent, stabilizing in different extent the more polar KE and KK. The further increase of the polarity of the environment by

• precoated TLC plates (0.2 mm thick). The identity of all compounds was confirmed employing various spectroscopic techniques including NMR and HRMS–ESI high-resolution mass spectrometry. The 1H and 13C NMR spectra were recorded in CDCl3 or DMSO-d6 at 25 °C on a Bruker Ultrashield Plus 500 spectrometer using

• formed, was washed with water several times and dried. The crude material was purified by column chromatography on silica gel, eluting with dichloromethane. Evaporation of the solvent afforded the pure target compound as orange solid (0.26 g, 38% yield). 1H NMR (500 MHz, DMSO-d6) δ 14.7 (br s, 1H), 8.90

N-Salicyl-amino acid derivatives with antiparasitic activity from Pseudomonas sp. UIAU-6B

• Joy E. Rajakulendran,
• Emmanuel Tope Oluwabusola,
• Michela Cerone,
• Terry K. Smith,
• Olusoji O. Adebisi,
• Adefolalu Adedotun,
• Gagan Preet,
• Sylvia Soldatou,
• Hai Deng,
• Rainer Ebel and
• Marcel Jaspars

Beilstein J. Org. Chem. 2025, 21, 1388–1396, doi:10.3762/bjoc.21.103

• File 1, Figures S1–S4) of 1 measured in deuterated DMSO revealed well-defined proton signals identified as four aromatic sp2 methines, two aliphatic sp3 methines, a methyl group and four quaternary carbon signals at δC 157.7 (C-1), δC117.8 (C-6), δC 167.2 (C-7), and δC 172.9 (C-10). The presence of a

• isolated as a reddish oil and displayed a molecular ion in the positive mode HRESIMS at m/z 331.1403 from which its molecular formula, C16H18N4O4 (Δ: +0.7 ppm, 10 degrees of unsaturation, calcd. for C16H19N4O4, 331.1401) was established. The 1H NMR of 5 measured in DMSO-d6 displayed 13 proton signals which

• ; found 137.0213; NMR data see Supporting Information File 1, Figures S34–S36) [15]. In vitro cytotoxicity viability test for T. brucei The bloodstream form of T. brucei strain 427 was grown in modified HMI-9 media as previously described [2]. The EC50 value of each compound (dissolved in DMSO) was

Oxetanes: formation, reactivity and total syntheses of natural products

• Peter Gabko,
• Martin Kalník and
• Maroš Bella

Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101

Recent advances in oxidative radical difunctionalization of N-arylacrylamides enabled by carbon radical reagents

• Jiangfei Chen,
• Yi-Lin Qu,
• Ming Yuan,
• Xiang-Mei Wu,
• Heng-Pei Jiang,
• Ying Fu and
• Shengrong Guo

Beilstein J. Org. Chem. 2025, 21, 1207–1271, doi:10.3762/bjoc.21.98

• as the photocatalyst (Scheme 27). The reaction was carried out under blue LED irradiation in DMSO as the solvent, yielding valuable polycyclic quinazolinones in satisfactory yields. Furthermore, a variety of substituents on the phenyl ring of N-cyanamide alkenes, as well as a series of difluorinated

• oxidation, ultimately forming the final oxindole product 76a. Interestingly, the reaction proceeds via two distinct pathways depending on the presence of an alkene radical acceptor, with DMSO or dimethyl sulfone as the byproduct. In addition to transition-metal and photocatalyzed systems, several metal-free

Synthetic approach to borrelidin fragments: focus on key intermediates

• Yudhi Dwi Kurniawan,
• Zetryana Puteri Tachrim,
• Teni Ernawati,
• Faris Hermawan,
• Ima Nurasiyah and
• Muhammad Alfin Sulmantara

Beilstein J. Org. Chem. 2025, 21, 1135–1160, doi:10.3762/bjoc.21.91

• alcohol was then protected as a PMB ether. After deprotecting the THP group, the resulting secondary alcohol was converted to a tosyl ester, which underwent an SN2 reaction with sodium cyanide in DMSO, yielding compound 109 with stereochemical inversion. Interestingly, reduction of the cyanide group with

Investigations of amination reactions on an antimalarial 1,2,4-triazolo[4,3-a]pyrazine scaffold

• Henry S. T. Smith,
• Ben Giuliani,
• Kanchana Wijesekera,
• Kah Yean Lum,
• Sandra Duffy,
• Aaron Lock,
• Jonathan M. White,
• Vicky M. Avery and
• Rohan A. Davis

Beilstein J. Org. Chem. 2025, 21, 1126–1134, doi:10.3762/bjoc.21.90

• °C in 5% CO2. At 6 h, 5 µL of 600 µM resazurin, diluted in growth media, was added. Plates were further incubated for 6 h and measured for fluorescence at 530 nm excitation and 595 nm emission. The % inhibition was calculated using 0.4% DMSO (no inhibition) and 50 μM puromycin (100% inhibition) data

Recent advances in synthetic approaches for bioactive cinnamic acid derivatives

• Betty A. Kustiana,
• Galuh Widiyarti and
• Teni Ernawati

Beilstein J. Org. Chem. 2025, 21, 1031–1086, doi:10.3762/bjoc.21.85

• trimethylsulfoxonium iodide (TMSOI) with DMSO-d6, resulting in CH3/CD3 exchange. Furthermore, Chisholm and co-workers (2019) synthesized bulky cinnamate esters 61–64 utilizing a trichloroacetimidate-based alkylating agent in moderate to excellent yields via carbocation 65 formation upon trichloroacetamide release

Synthesis of pyrrolo[3,2-d]pyrimidine-2,4(3H)-diones by domino C–N coupling/hydroamination reactions

• Ruben Manuel Figueira de Abreu,
• Robin Tiedemann,
• Peter Ehlers and
• Peter Langer

Beilstein J. Org. Chem. 2025, 21, 1010–1017, doi:10.3762/bjoc.21.82

• , 4l, and 4m in dichloromethane (c = 1·10−5 M). Synthesis of 3a–h. Conditions: i) Br2 (1.0 equiv), Ac2O (1.5 equiv), AcOH, 25 °C, 1 h [25]; ii) aryl acetylene (1.2 equiv), Pd(PPh3)Cl2 (5 mol %), CuI (5 mol %), NEt3 (10 equiv), DMSO, 25 °C, 6 h [26]. Yields of isolated products. C–N cross-coupling

Harnessing tethered nitreniums for diastereoselective amino-sulfonoxylation of alkenes

• Shyam Sathyamoorthi,
• Appasaheb K. Nirpal,
• Dnyaneshwar A. Gorve and
• Steven P. Kelley

Beilstein J. Org. Chem. 2025, 21, 947–954, doi:10.3762/bjoc.21.78

• (Scheme 3A). The mesylate could be cleanly substituted with azide by heating substrate with excess NaN3 in DMSO (Scheme 3B). With an excess of Schwartz’s reagent, the carbonyl was cleanly reduced to give 1,3-oxazine 62. Contrary to what we had initially predicted from literature precedent, there was no

Recent advances in controllable/divergent synthesis

• Jilei Cao,
• Leiyang Bai and
• Xuefeng Jiang

Beilstein J. Org. Chem. 2025, 21, 890–914, doi:10.3762/bjoc.21.73

• generated the [1 + 1] macrocycle 39 as the sole product. In contrast, polar aprotic solvents such as dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), or acetonitrile (MeCN) favored precipitation of the [2 + 2] macrocycle 40. Notably, the macrocycle 40 underwent spontaneous structural reorganization

Unraveling cooperative interactions between complexed ions in dual-host strategy for cesium salt separation

• Zhihua Liu,
• Ya-Zhi Chen,
• Ji Wang,
• Qingling Nie,
• Wei Zhao and
• Biao Wu

Beilstein J. Org. Chem. 2025, 21, 845–853, doi:10.3762/bjoc.21.68

• ]. According to our previous results, the binding affinity of L with chloride, sulfate and phosphate is determined to be 2.2 × 102 M−1, 9.9 × 104 M−1, and 3.8 × 106 M−1, respectively (in DMSO) [31]. Such strong anion binding affinity has led to selective extraction of sulfate and phosphate from basic aqueous

• solution into chloroform and controllable release into acidic solution [32]. Very recently, it was found that the receptor L alone can further extract solid Li2SO4 into DMSO solution [33], where sulfate binding is sufficiently strong to drive the solid–liquid extraction. DFT calculations suggest that an

• binding Na+ and K+ by oligourea foldamers and macrocycles [37][38][39]. However, in the solid−liquid extraction of Li2SO4 in DMSO, addition of crown ether did not help to increase the extraction efficiency. This is because ion-dipole interactions are negligible in high polar solvent, and Li+ binding is

Orthogonal photoswitching of heterobivalent azobenzene glycoclusters: the effect of glycoligand orientation in bacterial adhesion

• Leon M. Friedrich and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2025, 21, 736–748, doi:10.3762/bjoc.21.57

• α-ᴅ-mannoside (MeMan) measured on the same plate as reference. This leads to relative inhibitory potencies, so-called RIP values. Because of limited water solubility, the samples had to be dissolved in DMSO and therefore, the effect of pure DMSO was also tested in every individual assay (cf

• . Supporting Information File 1, Figures S13–S16). DMSO is known for its bactericidal effect and still, the use of this organic solvent in bioassays is common [42]. In general, a DMSO concentration of less than 10% (v/v) is accepted as nontoxic [43]. In any case, the effect of DMSO in the assays was carefully

• the conditions applied for the assay. This inhibitory effect is due to DMSO, which had to be used to dissolve the sample. Consequently, the RIP relative to DMSO is approx. 1 for both isomers of 3 (cf. Supporting Information File 1, Table S6). In all other cases, comparison of the RIP(MeMan) and the