Pseudallenes A and B, new sulfur-containing ovalicin sesquiterpenoid derivatives with antimicrobial activity from the deep-sea cold seep sediment-derived fungus Pseudallescheria boydii CS-793

• Zhen Ying,
• Xiao-Ming Li,
• Sui-Qun Yang,
• Hong-Lei Li,
• Xin Li,
• Bin-Gui Wang and
• Ling-Hong Meng

Beilstein J. Org. Chem. 2024, 20, 470–478, doi:10.3762/bjoc.20.42

• using solvent chemical shifts (DMSO: δH/δC 2.50/39.52) as reference. HRESIMS data were measured using an API QSTAR Pulsar 1 mass spectrometer. HPLC was performed on a Dionex HPLC system equipped with a P680 pump, an ASI-100 automated sample injector, and a UVD340U multiple-wavelength detector controlled

• , the bacteria were cultivated in the LB broth medium at 37 °C for the human pathogenic bacteria, while the temperature was 28 °C for the aquatic pathogens, and they were prepared at a concentration of 1.5 × 108 CFU/mL. Tested compounds and positive control (chloramphenicol) were dissolved in DMSO to

• give a stock solution with DMSO as a negative control. Then, 95 μL of thus prepared bacteria and 5 μL of the above tested compounds or chloramphenicol (with the final concentration of 0.5, 1, 2, 4, 8, 16, 32, 64 μg/mL) were added into the 96-well plates and cultivated at 37 °C or 28 °C for 24 h

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

• Fisher Scientific. DMSO-d6 NMR solvent was purchased from Sigma-Aldrich. Nα-(5-Fluoro-2,4-dinitrophenyl)-ᴅ-leucinamide was purchased from TCI Chemicals. Authentic amino acid samples were purchased from Thermo Scientific. Sodium bicarbonate purchased from Fisher Chemical. 1D and 2D NMR experiments were

• recorded on a Varian INOVA 500 instrument (1H: 500 MHz; 13C: 125 MHz). The chemical shifts (δ) were expressed in ppm and recorded with reference to solvent signals (1H NMR: DMSO-d6 2.50 ppm; 13C NMR: DMSO-d6 39.5 ppm). Optical rotation was measured on a Jasco P-2000 polarimeter with a path length of 100 mm

• biosynthesis of unguisins B and J in A. heteromorphus CBS 117.55. 1D and 2D NMR data for 1 (1H: 500 MHz, 13C: 125 MHz; DMSO-d6). Supporting Information Supporting Information File 36: Spectroscopic and spectrometric data of 1 and 2. Bioinformatic data of the biosynthetic gene clusters. Acknowledgements We

Substitution reactions in the acenaphthene analog of quino[7,8-h]quinoline and an unusual synthesis of the corresponding acenaphthylenes by tele-elimination

• Ekaterina V. Kolupaeva,
• Narek A. Dzhangiryan,
• Alexander F. Pozharskii,
• Oleg P. Demidov and
• Valery A. Ozeryanskii

Beilstein J. Org. Chem. 2024, 20, 243–253, doi:10.3762/bjoc.20.24

• 1:1 (Scheme 2). Complex 9 is insoluble in most organic solvents, but it turned out to be unstable in DMSO-d6 solution, as evidenced by monitoring its 1Н NMR spectra (Supporting Information File 1, Figure S1). Figure S1a shows the spectrum of the starting quinoline 5, Figure S1b represents complex 9

• sunlight (especially on adsorbents), and basic dipolar solvents (DMSO, for example, causes rather rapid degradation) [23]. Note that nitro derivatives 10 or 11 are not formed when base 5 is kept in nitric acid (25 °C, excess of 65% HNO3, 24 h) which returns the starting compound unchanged. After that step

Photochromic derivatives of indigo: historical overview of development, challenges and applications

• Gökhan Kaplan,
• Zeynel Seferoğlu and
• Daria V. Berdnikova

Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23

• significant difference in the values of β-angles, which results in some differences in the densities [10]. The solubility of crystalline indigo is poor even in polar solvents such as aniline, nitrobenzene, phenol, phthalic anhydride, DMSO, and DMF upon heating. The reason for the low solubility and high

• of indigo in 1) DMSO, 2) DMF, 3) N-methyl-2-pyrrolidone. Bond length in the indigo molecule obtained from the single crystal X-ray analysis [12], the typical bond lengths in organic compounds [15] and the main resonance structures of indigo. The structure of the indigo chromophore (H-chromophore

• species. Zwitterionic resonance structures of Z-indigo. Photos of crystalline N,N'-di(Boc)indigo 17a its solutions in 1) DMSO, 2) DMF, 3) N-methyl-2-pyrrolidone. Structural isomers of indigo. Photochromism of indirubin derivatives and supramolecular complexation of the E-isomers with Schreiner’s thiourea

Chiral phosphoric acid-catalyzed transfer hydrogenation of 3,3-difluoro-3H-indoles

• Yumei Wang,
• Guangzhu Wang,
• Yanping Zhu and
• Kaiwu Dong

Beilstein J. Org. Chem. 2024, 20, 205–211, doi:10.3762/bjoc.20.20

• achieving high selectivity. Also, an obvious solvent effect on the enantioselectivity was observed (Table 1, entries 7–10). Very low ee values of product 2a were detected when the reaction was performed in DMSO or MeOH (Table 1, entries 7 and 8), while using DCE or toluene as the solvent the

Metal-catalyzed coupling/carbonylative cyclizations for accessing dibenzodiazepinones: an expedient route to clozapine and other drugs

• Amina Moutayakine and
• Anthony J. Burke

Beilstein J. Org. Chem. 2024, 20, 193–204, doi:10.3762/bjoc.20.19

• °C; 1H NMR (DMSO-d6, 400 MHz) δ 6.87–7.00 (m, Ar, 6H), 7.31–7.35 (t, J = 8 Hz, Ar, 1H), 7.66–7.68 (d, J = 8 Hz, Ar,1H), 7.84 (s, Ar, 1H), 9.85 (s, Ar, 1H); 13C NMR (CDCl3, 100 MHz) δ 119.52, 120.23, 121.17, 121.73, 123.24, 123.40, 124.95, 130.29, 132.56, 133.67, 140.43, 150.92, 168.40; ESIMS (m/z

Synthesis of the 3’-O-sulfated TF antigen with a TEG-N₃ linker for glycodendrimersomes preparation to study lectin binding

• Mark Reihill,
• Hanyue Ma,
• Dennis Bengtsson and
• Stefan Oscarson

Beilstein J. Org. Chem. 2024, 20, 173–180, doi:10.3762/bjoc.20.17

• oxide (D2O) or DMSO-d6 ((CD3)2SO). 1H NMR spectra were standardised against the residual solvent peak (CDCl3, δ = 7.26 ppm; CD3OD, δ = 3.31 ppm; D2O, δ = 4.79 ppm; (CD3)2SO δ = 2.50 ppm); or internal trimethylsilane, δ = 0.00 ppm). 13C NMR spectra were standardised against the residual solvent peak

Copper-promoted C5-selective bromination of 8-aminoquinoline amides with alkyl bromides

• Changdong Shao,
• Chen Ma,
• Li Li,
• Jingyi Liu,
• Yanan Shen,
• Chen Chen,
• Qionglin Yang,
• Tianyi Xu,
• Zhengsong Hu,
• Yuhe Kan and
• Tingting Zhang

Beilstein J. Org. Chem. 2024, 20, 155–161, doi:10.3762/bjoc.20.14

• , China 10.3762/bjoc.20.14 Abstract An efficient and practical method for the synthesis of C5-brominated 8-aminoquinoline amides via a copper-promoted selective bromination of 8-aminoquinoline amides with alkyl bromides was developed. The reaction proceeds smoothly in dimethyl sulfoxide (DMSO) under air

• reaction parameters (Table 1). The treatment of 1a with 2a (4.0 equiv) in the presence of FeCl3 (20 mol %) and K3PO4 (1.0 equiv) in DMSO at 100 °C for 12 h gave the brominated product 3aa in 65% yield (Table 1, entry 1). The bromination was found to selectively take place at the C5-position of the

• probable mechanism is proposed. As shown in Scheme 5, ethyl bromoacetate (2a) undergoes attack by the dipolar aprotic solvent DMSO to afford the intermediate A. This intermediate then reacts with the bromine anion to give intermediate B. Dimethylsulfonium bromide or dimethyl thioether/molecular bromine

Photoinduced in situ generation of DNA-targeting ligands: DNA-binding and DNA-photodamaging properties of benzo[c]quinolizinium ions

• Julika Schlosser,
• Olga Fedorova,
• Yuri Fedorov and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 101–117, doi:10.3762/bjoc.20.11

• ). To clarify whether the mechanism of the DNA photodamage proceeds through the formation of radicals, experiments with commmonly employed radical scavengers were conducted (Table 3, Supporting Information File 1, Figure S17). In the presence of hydroxyl-radical scavengers DMSO, t-BuOH, and 2-propanol

• to the residual proton signal of the solvent [CD3CN: δ(1H) = 1.94 ppm, δ(13C) = 118.36 ppm or DMSO-d5: δ(1H) = 2.50 ppm, δ(13C) = 39.52 ppm] or to an internal standard in CDCl3 [TMS: δ(1H) = 0.00 ppm, δ(13C) = 0.00 ppm]. Structural assignments were made with additional information from gCOSY, gHSQC

Multi-redox indenofluorene chromophores incorporating dithiafulvene donor and ene/enediyne acceptor units

• Christina Schøttler,
• Kasper Lund-Rasmussen,
• Line Broløs,
• Philip Vinterberg,
• Ema Bazikova,
• Viktor B. R. Pedersen and
• Mogens Brøndsted Nielsen

Beilstein J. Org. Chem. 2024, 20, 59–73, doi:10.3762/bjoc.20.8

• CH2Cl2 (CD2Cl2, 1H = 5.32 ppm, 13C = 54.00 ppm), deuterated DMSO ((CD3)2SO, 1H = 2.50 ppm, 13C = 39.53 ppm), deuterated acetone ((CD3)2CO, 1H = 2.05 ppm, 13C = 29.84 ppm), or deuterated benzene (C6D6, 1H = 7.16 ppm, 13C = 128.39 ppm) were used as solvents and internal references. Chemical shift values

Using the phospha-Michael reaction for making phosphonium phenolate zwitterions

• Matthias R. Steiner,
• Max Schmallegger,
• Larissa Donner,
• Johann A. Hlina,
• Christoph Marschner,
• Judith Baumgartner and
• Christian Slugovc

Beilstein J. Org. Chem. 2024, 20, 41–51, doi:10.3762/bjoc.20.6

• phosphorus signal for 2d). Stability tests were also performed in two different deuterated solvents, CDCl3 and DMSO-d6. No air or moisture exclusion was applied. The tests were performed at room temperature and at 60 °C. 1H and 31P NMR spectra of the solutions were taken after 24, 48 and 72 h. At room

• temperature the observable decomposition after 72 h is very low in both solvents. NMR spectra (1H and 31P) show trace amounts of the phosphine oxide of 1. The total amount of phosphine oxide is somewhat lower in DMSO-d6 when compared to CDCl3. Additionally, in CDCl3 further unknown decomposition products were

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

• , 0.5 mmol; 1,4-dioxane (2 mL)) as a colorless powder; mp 225–226 °C; 1H NMR (400 MHz, DMSO-d6) δ 3.16 (s, 3H), 3.21 (s, 3H), 5.08 (s, 1H), 5.46 (s, 2H), 6.52 (s, 1H), 6.53 (s, 1H), 7.19 (br. s, 2H), 7.25–7.39 (m, 5H); 13C NMR (101 MHz, DMSO-d6) δ 27.1, 29.8, 48.4, 87.4, 120.9, 127.4, 127.6, 128.5

• NMR (400 MHz, DMSO-d6) δ 5.48 (s, 2H), 6.68 (s, 1H), 6.69 (s, 1H), 7.10 (d, J = 3.9 Hz, 1H), 7.24 (d, J = 6.9 Hz, 2H), 7.28–7.38 (m, 3H), 7.43 (d, J = 3.9 Hz, 1H), 8.42 (br. s, 1H), 9.15 (br. s, 1H); 13C NMR (101 MHz, DMSO-d6) δ 48.5, 112.6, 121.2, 127.2, 127.6, 128.5, 135.7, 138.8, 143.6, 153.5

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

• a linear gradient of chloroform/methanol. Fractions containing compound 6 were concentrated by evaporation. The residual materials were desorbed in 1 mL DMSO and applied to a reversed-phase high-performance liquid chromatography (HPLC, Shimadzu Corp.) equipped with a COSMOCORE Packed column 5C18-AR

• -II (10 mm ID × 250 mm, Nacalai Tesque), and the metabolites were eluted with a linear gradient of water/acetonitrile containing 0.1% formic acid. Fractions containing compound 6 were concentrated by evaporation. Compound 6 was then desorbed in DMSO-d6, and the structure was determined by the JNM-A600

Aromatic systems with two and three pyridine-2,6-dicarbazolyl-3,5-dicarbonitrile fragments as electron-transporting organic semiconductors exhibiting long-lived emissions

• Karolis Leitonas,
• Brigita Vigante,
• Dmytro Volyniuk,
• Audrius Bucinskas,
• Pavels Dimitrijevs,
• Sindija Lapcinska,
• Pavel Arsenyan and
• Juozas Vidas Grazulevicius

Beilstein J. Org. Chem. 2023, 19, 1867–1880, doi:10.3762/bjoc.19.139

• volume and after cooling the precipitate was filtered. The crude product was washed with cold MeOH and EtOAc and dried under reduced pressure yielding 2 (7.40 g, 35%) as white powder, which was used in the next reaction without further purification. 1H NMR (400 MHz, DMSO-d6) 7.67–7.66 (m, 2H), 7.37–7.33

• for 1 h. After cooling, the reaction was quenched by the addition of ice and the precipitate was filtered off. The crude product was purified by flash chromatography on silica gel using chloroform as eluent yielding compound 3 (1.0 g, 78%) as white powder. Mp > 200 °C; 1H NMR (400 MHz, DMSO-d6) 7.91

A novel recyclable organocatalyst for the gram-scale enantioselective synthesis of (S)-baclofen

• Gyula Dargó,
• Dóra Erdélyi,
• Balázs Molnár,
• Péter Kisszékelyi,
• Zsófia Garádi and
• József Kupai

Beilstein J. Org. Chem. 2023, 19, 1811–1824, doi:10.3762/bjoc.19.133

• further purifications. TLC (SiO2; DCM/MeOH/25% NH4OH(aq) 10:1:0.01, Rf 0.22); mp 158–160 °C; −51.8 (c 1.00, DMSO); IR (cm−1) νmax: 2957, 2923, 2853, 1664, 1620, 1609, 1560, 1508, 1437, 1378, 1331, 1277, 1201, 1175, 1126, 1021, 930, 884, 832, 799, 719, 700, 679, 620, 550, 521, 414; 1H NMR (500 MHz, MeOH

Synthetic approach to 2-alkyl-4-quinolones and 2-alkyl-4-quinolone-3-carboxamides based on common β-keto amide precursors

• Yordanka Mollova-Sapundzhieva,
• Plamen Angelov,
• Danail Georgiev and
• Pavel Yanev

Beilstein J. Org. Chem. 2023, 19, 1804–1810, doi:10.3762/bjoc.19.132

• additional decarbamoylative step (Scheme 2). The decarbamoylation of compounds 3a–d was carried out by heating at 60 °C in neat H3PO4 for 90 minutes [62] and gave the corresponding β-enaminoketones 6a–d in good yields (Table 2). The NMR spectra of compounds 6 in DMSO-d6 in all cases indicated a mixture of Z

• . coli, using the hole-plate method in Mueller–Hinton agar, with 100 µg loading of each compound in 100 µL DMSO (Table 6). Interestingly, at this concentration most of the compounds showed weak to moderate activity against E. coli, while S. aureus was inhibited only by C5 and C7-substituted analogs

Unprecedented synthesis of a 14-membered hexaazamacrocycle

• Anastasia A. Fesenko and
• Anatoly D. Shutalev

Beilstein J. Org. Chem. 2023, 19, 1728–1740, doi:10.3762/bjoc.19.126

• NMR spectrum in DMSO-d6 shows the presence of two methylpyrazole moieties (singlet signals of two methyl groups at 3.63 and 3.70 ppm, singlet signals of two CH protons of pyrazole rings at 7.81 and 7.84 ppm), a H–N–C–H fragment with trans-orientation of protons (two doublets at 9.87 and 7.50 ppm, 3J

• the 1H,13C-HSQC and 1H,13C-HMBС spectra, as well as by comparing the experimental carbon chemical shifts in DMSO-d6 with those calculated for 6 by the GIAO method at the PBE1PBE/6-311+G(2d,p) level of theory using the DFT B3LYP/6-311++G(d,p) optimized geometries (DMSO solution) and applying a multi

• the 1H and 13C{1H} NMR spectra of compound 5 in DMSO-d6 show only a half-number set of proton or carbon signals (five and six signals, respectively), thus indicating its C2-symmetric dimeric structure. The analysis of 2D NMR spectroscopic data provided additional evidence for the macrocycle 5

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

• intensity bands, respectively, at 1519 and 1336 cm−1. These modes were calculated at 1608 and 1379 cm−1 in the gas phase. Although N-acylhydrazones are usually prone to undergo speciation in DMSO-d6 solution [47], 1H NMR measurements showed the existence of only one set of signals in the spectra of hdz-CH3

• stability in aqueous medium. Thus, the electronic absorption spectra of hdz-CH3 and hdz-NO2 were recorded in a 10% DMSO/buffer solution (pH 7.4) immediately after preparation and at regular time intervals. The UV–vis spectrum of hdz-CH3 between 250 and 450 nm (Figure 6A) shows two multicomponent absorptions

• -up study in solution (Figure 6B), indicating that the compound is stable in a water-rich medium. The spectrum of hdz-CH3 in DMSO, a solvent in which N-acylhydrazones are usually considered long-lived species, is included in the figure for the sake of comparison. Thus, the presence of the methyl

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

• appropriate concentrations by dissolving in DMSO and diluting 1000-fold in medium. RAW 264.7 cells were preincubated with fresh medium containing test samples or vehicle (DMSO) for 24 h. After preincubation, LPS was added at a final concentration of 50 ng/mL. qRT-PCR analysis Total RNA was extracted using

Lewis acid-promoted direct synthesis of isoxazole derivatives

• Dengxu Qiu,
• Chenhui Jiang,
• Pan Gao and
• Yu Yuan

Beilstein J. Org. Chem. 2023, 19, 1562–1567, doi:10.3762/bjoc.19.113

• compared with DMSO and DMF (Table 1, entries 8 and 9). The reaction yield was decreased to 21% when increasing the temperature to 140 °C under standard conditions (Table 1, entry 10). Finally, the nitrogen atmosphere was essential since the yield substantially decreased under air atmosphere (Table 1, entry

Secondary metabolites of Diaporthe cameroonensis, isolated from the Cameroonian medicinal plant Trema guineensis

• Bel Youssouf G. Mountessou,
• Élodie Gisèle M. Anoumedem,
• Blondelle M. Kemkuignou,
• Yasmina Marin-Felix,
• Frank Surup,
• Marc Stadler and
• Simeon F. Kouam

Beilstein J. Org. Chem. 2023, 19, 1555–1561, doi:10.3762/bjoc.19.112

• min), and 15 (1.23 mg, white oil). 5,7-Dimethylpseudopithonone (1): yellow oil, 0 (c 0.27, MeOH); UV (MeOH): λmax (PDA): 218, 290, 342 nm; 1H NMR (500 MHz, CD3OD) and 13C NMR (125 MHz, DMSO-d6) are shown in Table 1; (+)-HRESIMS (m/z): [M + H]+ calcd for C12H15O4, 223.0965; found, 223.0961. 3,9

• -Diacetylalternariol (2): white amorphous powder, UV (MeOH): λmax (PDA): 222, 258, 330 nm; 1H NMR (500 MHz, DMSO-d6) and 13C NMR (125 MHz, DMSO-d6) are shown in Table 1; (+)-HRESIMS (m/z): [M + H]+ calcd for C18H15O7, 343.0812; found, 343.0809. Chemical structures of compounds 1 and 2. Key COSY and HMBC correlations

• of compounds 1 and 2. 1H (500 MHz) and 13C (125 MHz) NMR data of compounds 1 and 2 in DMSO-d6. Supporting Information Supporting Information File 2: HRESIMS data and 1H, 13C, COSY, HSQC, and HMBC NMR spectra of compounds 1 and 2. Acknowledgements We thank C. Kakoschke for the measurement of NMR

Synthesis of 5-arylidenerhodanines in L-proline-based deep eutectic solvent

• Stéphanie Hesse

Beilstein J. Org. Chem. 2023, 19, 1537–1544, doi:10.3762/bjoc.19.110

• same protocol as described by Molnar et al. [43] where DPPH and the synthesized compounds were tested in a solution at 0.2 mM concentration in DMSO as solvent. Because phenolic compounds can be easily oxidized to quinones, it is well known that most hydroxylated compounds have antioxidant properties

• -Hydroxymethylfurfurylidene)-2-thioxothiazolidin-4-one (3j). ochre yellow solid obtained after 1 h at 60 °C in 36% yield (two-step yield). Mp 149 °C; 1H NMR (400 MHz, DMSO-d6) δ (ppm) 4.49 (s, 2H), 5.52 (br s, 1H, OH), 6.58 (d, J = 3.6 Hz, 1H), 7.11 (d, J = 3.6 Hz, 1H), 7.44 (s, 1H, =CH), 13.62 (br s, 1H, NH); 13C NMR (100

• MHz, DMSO-d6) δ (ppm) 196.8, 169.1, 161.2, 148.8, 121.8, 121.0, 117.8, 110.9, 56.0. HRMS–ESI− (m/z): [M]− calcd for C9H6NO3S2: 240.982814; found, 240.982805. DPPH-scavenging activity Determination of antioxidant activity was performed according to the procedure described in the literature [21]. A DMSO

Complexes of resorcin[4]arene with secondary amines: synthesis, solvent influence on “in-out” structure, and theoretical calculations of non-covalent interactions

• Waldemar Iwanek

Beilstein J. Org. Chem. 2023, 19, 1525–1536, doi:10.3762/bjoc.19.109

• exchange and dispersion interactions in CHCl3 in relation to DMSO are the driving forces behind the placement of sec-amine molecules into the R[4]A cavity and the formation of “in” type complexes. Keywords: complexes; DFT calculations; hydrogen bond; resorcin[4]arene; supramolecular chemistry

• stoichiometry complexes recorded in DMSO-d6 and CDCl3 solution are very different. On the other hand, complexes with a 1:2 stoichiometry are insoluble in CDCl3, hence their further analysis is limited to the solution in DMSO. Figure 1 shows the 1H NMR spectra of the 1:1 complex of R[4]A with pyrrolidine in DMSO

• -d6 and CDCl3, respectively. In DMSO, the resonances of the triplet and multiplet protons of the pyrrolidine molecule are located at 2.77 ppm and 1.62 ppm, respectively. On the other hand, in CDCl3, the protons of the pyrrolidine molecule are located at the following ppm: 3.59 (t), 3.51(t), 1.96 (m

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

• original berberine used a DMSO solution [11]. Thus, we reevaluated a number of variants and berberine itself using DMSO solutions at the same concentrations. Several results showed comparable zones of inhibition to those collected with methanol solutions, with one significant exception. When tested against

• S. aureus, the DMSO solutions were roughly 1.4 times more potent than results with the methanol solution (see Supporting Information File 1). This improved potency was seen for original berberine as well as the variants tested. Variants that were inactive as methanol solutions remained inactive when

• their DMSO solutions were tested. While this was a notable improvement against S. aureus, the general trends in potency were in agreement with those presented in Table 1. Furthermore, some organisms showed a weak zone of inhibition with the DMSO blank. This fact, coupled with the general trends in

Application of N-heterocyclic carbene–Cu(I) complexes as catalysts in organic synthesis: a review

• Nosheen Beig,
• Varsha Goyal and
• Raj K. Bansal

Beilstein J. Org. Chem. 2023, 19, 1408–1442, doi:10.3762/bjoc.19.102

• DMSO. However, the Cu(I) complex 54 was obtained in trace amounts only (Scheme 18) [31]. This complex could be obtained in good yield through transmetallation of the corresponding Ag complex as discussed later in Scheme 24. Douthwaite and co-workers reported the synthesis of Cu(I) bromide complexes 56a