Photoswitchable glycoligands targeting Pseudomonas aeruginosa LecA

• Yu Fan,
• Ahmed El Rhaz,
• Stéphane Maisonneuve,
• Emilie Gillon,
• Maha Fatthalla,
• Franck Le Bideau,
• Guillaume Laurent,
• Samir Messaoudi,
• Anne Imberty and
• Juan Xie

Beilstein J. Org. Chem. 2024, 20, 1486–1496, doi:10.3762/bjoc.20.132

• silica gel (60 Å pore size, 40–63 µm). 1H and 13C NMR spectra were recorded on a JEOL ECS-400 spectrometer or on Bruker Avance 300 and 400 spectrometers. Structural assignments were made with additional information from gCOSY, HMBC, and gHMQC experiments. High-resolution mass spectra (HRMS) were

Synthesis of 2-benzyl N-substituted anilines via imine condensation–isoaromatization of (E)-2-arylidene-3-cyclohexenones and primary amines

• Lu Li,
• Na Li,
• Xiao-Tian Mo,
• Ming-Wei Yuan,
• Lin Jiang and
• Ming-Long Yuan

Beilstein J. Org. Chem. 2024, 20, 1468–1475, doi:10.3762/bjoc.20.130

• -cyclohexenone. This is further supported by the 13C NMR spectrum, which contains two peaks at δ = 38.4 and 47.7 indicating the two types of benzylic carbons. The NMR data of known compound 4ab were also in good correlation with previously reported data [19]. The synthetic practicability of the protocol was

Selectfluor and alcohol-mediated synthesis of bicyclic oxyfluorination compounds by Wagner–Meerwein rearrangement

• Ziya Dağalan,
• Muhammed Hanifi Çelikoğlu,
• Saffet Çelik,
• Ramazan Koçak and
• Bilal Nişancı

Beilstein J. Org. Chem. 2024, 20, 1462–1467, doi:10.3762/bjoc.20.129

• rearrangement. Optimizing the conditions for the oxyfluorination of bicyclic alkenesa. Supporting Information Supporting Information File 2: Experimental procedures, copies of 1H NMR, 13C NMR, and HRMS(Q-TOF) spectra. Acknowledgements The authors wish to express their sincerest gratitude to Dr. Barış Anıl for

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

• ), 2.28 (s, 3H, CH3), 1.89–1.86 (m, 2H, CH2), 1.80–1.68 (m, 4H, CH2), 1.55–1.33 (m, 3H, CH2), 1.20–1.13 (m, 1H, CH2) ppm; 13C NMR (100 MHz, CDCl3) δ 170.1, 168.3, 167.8, 166.5, 162.5, 161.9, 157.2, 157.0, 144.7, 137.6, 131.4, 130.9, 129.1, 128.0, 127.9, 127.1, 112.0, 113.6, 111.0, 110.2, 98.9, 84.0, 72.2

• 2346135) and 6g (CCDC 2346136) have been deposited at the Cambridge Crystallographic Database Center (http://www.ccdc.cam.ac.uk). Supporting Information File 24: Characterization data and 1H NMR, 13C NMR, and HRMS spectra of compounds. Funding This work was financially supported by the National Natural

Rhodium-catalyzed homo-coupling reaction of aryl Grignard reagents and its application for the synthesis of an integrin inhibitor

• Kazuyuki Sato,
• Satoki Teranishi,
• Atsushi Sakaue,
• Yukiko Karuo,
• Atsushi Tarui,
• Kentaro Kawai,
• Hiroyuki Takeda,
• Tatsuo Kinashi and
• Masaaki Omote

Beilstein J. Org. Chem. 2024, 20, 1341–1347, doi:10.3762/bjoc.20.118

• Information Supporting Information File 98: General procedures and analytical data, including copies of 1H NMR and 13C NMR spectra. Acknowledgements We would like to thank Dr. Antal Harsányi at Euroapi Hungary for his helpful comments to improve the quality of the article.

Synthesis of 1,2,3-triazoles containing an allomaltol moiety from substituted pyrano[2,3-d]isoxazolones via base-promoted Boulton–Katritzky rearrangement

• Constantine V. Milyutin,
• Andrey N. Komogortsev and
• Boris V. Lichitsky

Beilstein J. Org. Chem. 2024, 20, 1334–1340, doi:10.3762/bjoc.20.117

• hydrazones also can be utilized in the considered rearrangement. It should be mentioned that the presented reaction is the first example of a recyclization of the pyrano[2,3-d]isoxazolone core. The obtained 1,2,3-triazoles 4 are solid crystalline products, whose structures were proved by 1H, 13C NMR

• obtained the recyclized product 6a (Scheme 6), whose structure was confirmed by 1H, 13C NMR spectroscopy, high-resolution mass spectrometry and X-ray analysis. Based on the aforementioned reaction we have synthesized a set of pyrazolylisoxazoles 6 (Scheme 7). The proposed mechanism of investigated

• File 96: Experimental procedures, characterization data of all products, copies of 1H, 13C NMR, spectra of all new compounds, and X-ray crystallographic data. Acknowledgements The crystal structure determination was performed in the Department of Structural Studies of Zelinsky Institute of Organic

Sustainable tandem acylation/Diels–Alder reaction toward versatile tricyclic epoxyisoindole-7-carboxylic acids in renewable green solvents

• Ayhan Yıldırım

Beilstein J. Org. Chem. 2024, 20, 1308–1319, doi:10.3762/bjoc.20.114

• the bis structure are in equilibrium with maleamic acid precursors (Scheme 3) complicates the interpretation of their 1H and 13C NMR spectra. The existence of these precursors is clearly demonstrated by both their 1H and 13C NMR spectra (Supporting Information File 1). It should be noted that in the

• ), 4.63 (d, J = 15.1 Hz, 1H, Hh), 4.42 (d, J = 15.1 Hz, 1H, Hi), 3.83 (d, J = 12 Hz, 1H, Hd), 3.65 (d, J = 12 Hz, 1H, He), 2.96 (d, J = 9.1 Hz, 1H, Ha), 2.84 (d, J = 9.1 Hz, 1H, Hb); 13C NMR (150 MHz, CDCl3) δ 173.10, 172.51, 137.22, 135.20, 134.83, 128.92, 127.98, 127.87, 88.79, 82.36, 50.72, 48.53

Diameter-selective extraction of single-walled carbon nanotubes by interlocking with Cu-tethered square nanobrackets

• Guoqing Cheng and
• Naoki Komatsu

Beilstein J. Org. Chem. 2024, 20, 1298–1307, doi:10.3762/bjoc.20.113

• (Scheme 2) [11]. The products were fully characterized by 1H and 13C NMR, and MALDI-TOF mass spectroscopy (see Supporting Information File 1). The total yield of 4b (5.5%) based on 2,7-dibromopyrene is much lower than that of 4a (44%) [11], because a larger amount of the product 4b was lost in the

• measurements and analyzed with mMass [29] software. 1H and 13C NMR spectra were recorded on JNM-ECS 400 spectrometer using the sample solutions in chloroform-d (CDCl3). Raman spectra were recorded on LabRam HR800 (Horiba Ltd.) and take the average of more than ten different spots for the final curve. UV–Vis

• , rt, 1.5 h; iv) p-chloranil, dichloromethane, rt, 5 h. Supporting Information Supporting Information File 86: Details of theoretical calculations, experimental procedures, copies of 1H and 13C NMR spectra. Acknowledgements Computation time was provided by supercomputer system, Academic Center for

Synthesis of indano[60]fullerene thioketone and its application in organic solar cells

• Yong-Chang Zhai,
• Shimon Oiwa,
• Shinobu Aoyagi,
• Shohei Ohno,
• Tsubasa Mikie,
• Jun-Zhuo Wang,
• Hirofumi Amada,
• Koki Yamanaka,
• Kazuhira Miwa,
• Naoyuki Imai,
• Takeshi Igarashi,
• Itaru Osaka and
• Yutaka Matsuo

Beilstein J. Org. Chem. 2024, 20, 1270–1277, doi:10.3762/bjoc.20.109

• of Lawesson's reagent and the reaction temperature. The transformation from ketone to thioketone was confirmed by 13C NMR, which showed a downfield shift from 198 ppm for the carbonyl carbon to 235 ppm for the thiocarbonyl carbon. With the optimized conditions (Table 1, entry 9) in hand, different

Competing electrophilic substitution and oxidative polymerization of arylamines with selenium dioxide

• Vishnu Selladurai and
• Selvakumar Karuthapandi

Beilstein J. Org. Chem. 2024, 20, 1221–1235, doi:10.3762/bjoc.20.105

• + Na]+, [2M + Na]+, and [3M + Na]+. Spectroscopic data of this compound, including FTIR as well as 1H and 13C NMR, matched those reported earlier [54]. Relative extent of polymerization To compare the relative polymerization tendency, we conducted reactions of arylamines with SeO2 in acetonitrile in

• account. Characterization of the organoselenium compounds by HRMS, 1H, and 13C NMR was supported by 77Se NMR and single-crystal X-ray analysis in order to confirm the identity of the compounds. Experimental General procedures All syntheses were carried out using the standard Schlenk line in a nitrogen

• , 6H); 13C NMR (126 MHz, CDCl3, δ) 157.5, 148.9, 126.2, 125.3, 121.0, 119.7, 110.3, 55.8; HRESIMS (m/z): [M + Na]+ calcd for C16H16N2NaO4, 323.1002; found, 323.1006, [2M + Na]+ calcd for C32H32N4NaO8, 623.2112; found, 623.2112, [3M + Na]+ calcd for C48H48N6NaO12, 923.3222; found, 923.3201; FTIR (KBr

Introduction of peripheral nitrogen atoms to cyclo-meta-phenylenes

• Koki Ikemoto and
• Hiroyuki Isobe

Beilstein J. Org. Chem. 2024, 20, 1207–1212, doi:10.3762/bjoc.20.103

• total, 3a was obtained in 7% yield (325 mg, 0.707 mmol). N3-[6]CMP (3a): 1H NMR (CDCl3, 600 MHz) δ 9.05 (d, J = 2.1 Hz, 6H), 8.58 (t, J = 2.1 Hz, 3H), 8.23 (t, J = 2.1 Hz, 3H), 7.89 (dd, J = 7.6, 2.1 Hz, 6H), 7.69 (t, J = 7.6 Hz, 3H); 13C NMR (CDCl3, 150 MHz) δ 146.6 (CH), 138.3, 135.7, 133.9 (CH

• ), 130.2 (CH), 127.5 (CH), 125.9 (CH); HRMS (APCI) (m/z): [M + H]+ calcd. for C33H22N3, 460.1808; found, 460.1808. N4-[8]CMP (3b): 1H NMR (CDCl3, 600 MHz) δ 8.81 (d, J = 1.4 Hz, 8H), 8.13 (t, J = 1.4 Hz, 4H), 7.76 (s, 4H), 7.66–7.73 (m, 12H); 13C NMR (CDCl3, 150 MHz) δ 147.9 (CH), 139.2, 137.0, 133.5 (CH

Two-fold addition reaction of silylene to C₆₀: structural and electronic properties of a bis-adduct

• Masahiro Kako,
• Masato Kai,
• Masanori Yasui,
• Michio Yamada,
• Yutaka Maeda and
• Takeshi Akasaka

Beilstein J. Org. Chem. 2024, 20, 1179–1188, doi:10.3762/bjoc.20.100

• ). In the 13C NMR spectrum, a total of 43 signals were observed in the low-field region (approximately 160–120 ppm), of which 29 signals are attributed to the C60 carbon cage and 14 signals are attributed to the aromatic ring carbon nuclei of the Dip groups (Figure 4). In addition, three sp3 carbon

• . Reagents were used as purchased unless otherwise specified. The 1H and 13C NMR measurements were conducted on a JEOL ECA-500 spectrometer (JEOL Ltd.). Absorption spectra were measured using a UV-3150 spectrophotometer (Shimadzu Corp.). Cyclic voltammograms and differential pulse voltammograms were recorded

• Hz, 6H), 1.371 (d, J = 7.0 Hz, 6H), 1.365 (d, J = 7.0 Hz, 6H), 1.31 (d, J = 7.0 Hz, 6H), 1.29 (d, J = 7.0 Hz, 6H), 1.17 (d, J = 7.0 Hz, 6H), 1.06 (d, J = 7.0 Hz, 6H); 13C NMR (CDCl3/CS2 3:1) δ 160.16 (s, 2C), 158.38 (s, 2C), 158.33 (s, 2C), 158.29 (s, 2C), 158.18 (s, 2C), 157.12 (s, 2C), 155.78 (s

Bismuth(III) triflate: an economical and environmentally friendly catalyst for the Nazarov reaction

• Manoel T. Rodrigues Jr.,
• Aline S. B. de Oliveira,
• Ralph C. Gomes,
• Amanda Soares Hirata,
• Lucas A. Zeoly,
• Hugo Santos,
• João Arantes,
• Catarina Sofia Mateus Reis-Silva,
• João Agostinho Machado-Neto,
• Leticia Veras Costa-Lotufo and
• Fernando Coelho

Beilstein J. Org. Chem. 2024, 20, 1167–1178, doi:10.3762/bjoc.20.99

• reactivity of 9dc,dl. Supporting Information Supporting Information File 26: Experimental section and copies of 1H and 13C NMR spectra of all new compounds. Funding The authors thank the São Paulo Foundation Science (FAPESP, #2018/02611-0, #2013/07600-3 and #2023/18007-3, to FC) for financial support. F. C

Kinetically stabilized 1,3-diarylisobenzofurans and the possibility of preparing large, persistent isoacenofurans with unusually small HOMO–LUMO gaps

• Qian Liu and
• Glen P. Miller

Beilstein J. Org. Chem. 2024, 20, 1099–1110, doi:10.3762/bjoc.20.97

• spectroscopy. After 51 hours of reaction in boiling CH2Cl2, Diels–Alder adduct 27 was observed in 22% yield. Compound 27 was identified by 1H NMR and 13C NMR spectroscopies as well as high-resolution ESI mass spectrometry. Although the lack of reactivity observed for 3 and 23 limited our kinetic analysis, we

• modified cardboard box were utilized for detection of TLC spots. Melting points were determined in open capillary tubes using a Mel-Temp apparatus, and are uncorrected. Proton nuclear magnetic resonance (1H NMR) spectra and carbon nuclear magnetic resonance (13C NMR) spectra were recorded on either a

• , washed with 5 mL water, and then air dried to give 3 as a white solid (57 mg, 60%, Scheme 3). Mp 169–170 °C (from [13], 188–189 °C); 1H NMR (500 MHz, CDCl3) δ 7.15–7.08 (m, 2H), 6.98 (s, 4H), 6.86–6.79 (m, 2H), 2.35 (s, 6H), 2.12 (s, 12H); 13C NMR (126 MHz, CDCl3) δ 143.54, 139.17, 138.71, 128.23, 127.43

Synthesis of 1,4-azaphosphinine nucleosides and evaluation as inhibitors of human cytidine deaminase and APOBEC3A

• Maksim V. Kvach,
• Stefan Harjes,
• Harikrishnan M. Kurup,
• Geoffrey B. Jameson,
• Elena Harjes and
• Vyacheslav V. Filichev

Beilstein J. Org. Chem. 2024, 20, 1088–1098, doi:10.3762/bjoc.20.96

• anomers with a α/β ratio of 2:1, as determined by 1H and 13C NMR. Deprotected nucleosides Va and Vb but not Vc exhibited absorbance in the UV region with ε258 = 4230 L⋅mol−1⋅cm−1 and ε262 = 4730 L⋅mol−1⋅cm−1, respectively. This was most likely a result of the presence of a double bond next to the P=O unit

Mild and efficient synthesis and base-promoted rearrangement of novel isoxazolo[4,5-b]pyridines

• Vladislav V. Nikol’skiy,
• Mikhail E. Minyaev,
• Maxim A. Bastrakov and
• Alexey M. Starosotnikov

Beilstein J. Org. Chem. 2024, 20, 1069–1075, doi:10.3762/bjoc.20.94

• inhibitor of homeodomain-interacting protein kinases (HIPKs) [32], and combretastatin A-4 analogs evaluated for their anticancer properties against a panel of 60 human cancer cell lines [33] (Figure 2). The structures of all new compounds were confirmed by 1H and 13C NMR and HRMS. X-ray diffraction studies

Structure–property relationships in dicyanopyrazinoquinoxalines and their hydrogen-bonding-capable dihydropyrazinoquinoxalinedione derivatives

• Tural N. Akhmedov,
• Ajeet Kumar,
• Daken J. Starkenburg,
• Kyle J. Chesney,
• Khalil A. Abboud,
• Novruz G. Akhmedov,
• Jiangeng Xue and
• Ronald K. Castellano

Beilstein J. Org. Chem. 2024, 20, 1037–1052, doi:10.3762/bjoc.20.92

• , 230−400 mesh from Whatman. Routine 300(75) MHz 1H(13C) NMR spectra were recorded on Varian Mercury 300 or Gemini 300 spectrometers. Routine 500(125) MHz 1H(13C) NMR were recorded on an INOVA 500 spectrometer. 2D NMR spectra were recorded using a 600 MHz Varian instrument. Chemical shifts (δ) are given

• amounts of CH2Cl2 and THF (10 mL), and dried in vacuo to afford a bright orange solid of 1a (0.264 g, 1.14 mmol, 89%). 1H NMR (600 MHz, DMSO-d6) δ 8.30–8.31 (dd, J = 3 Hz, J = 6.6 Hz, 2H), 8.49–8.51 (dd, J = 3 Hz, J = 6.6 Hz, 2H); 13C NMR (150 MHz, DMSO-d6) δ 114.5, 130.4, 136.1, 136.2, 142.7, 147.4; HRMS

• (s, 6H), 8.27 (s, 2H); 13C NMR (125 MHz, DMSO-d6) δ 20.1, 114.2, 127.8, 134.6, 142.3, 146.6, 148.7. The proton NMR in chloroform matches the literature value [25]; HRMS (DART): [M + H]+ calcd for C14H8N6, 261.0883; found, 261.0889; [M + NH4]+, 278.1149; found, 278.1154. Aceanthryleno[1,2-b]pyrazino

One-pot Ugi-azide and Heck reactions for the synthesis of heterocyclic systems containing tetrazole and 1,2,3,4-tetrahydroisoquinoline

• Jiawei Niu,
• Yuhui Wang,
• Shenghu Yan,
• Yue Zhang,
• Xiaoming Ma,
• Qiang Zhang and
• Wei Zhang

Beilstein J. Org. Chem. 2024, 20, 912–920, doi:10.3762/bjoc.20.81

• and 13C NMR, and HRMS analysis. In addition, single crystals of compound 6d and 8c were obtained for X-ray analysis to confirm the structures (Figure 2). Conclusion In conclusion, we have developed a one-pot synthesis with two or three steps for making tetrazolo-pyrazino[2,1-a]isoquinolin-6(5H)-ones

Skeletal rearrangement of 6,8-dioxabicyclo[3.2.1]octan-4-ols promoted by thionyl chloride or Appel conditions

• Martyn Jevric,
• Julian Klepp,
• Johannes Puschnig,
• Oscar Lamb,
• Christopher J. Sumby and
• Ben W. Greatrex

Beilstein J. Org. Chem. 2024, 20, 823–829, doi:10.3762/bjoc.20.74

• separated by 0.21 ppm. In the 13C NMR spectrum of 11a–f, a ≈10 ppm upfield shift for the chloroacetal was seen to δ ≈92 ppm from the C5 acetal present in the starting materials. Only a single diastereomer was formed for all 3,3-disubstituted rearrangement products due to the hindrance on the endo-face, with

• open chain aldehydes present in solution (≈5%) with a doublet at δ 9.6 ppm, with the configuration of the hemiacetal centre confirmed in the solid state by X-ray crystallography on 12a and 12d. The 1H and 13C NMR spectra for 13b,d,e were similar to the starting materials, except that the resonances

• spectra. Supporting Information File 12: 1H and 13C NMR FIDs, HRMS spectra for all new compounds. Funding JP was supported by an Australian Government Research Training Program Scholarship and the Destination Australia Program.

Discovery and biosynthesis of bacterial drimane-type sesquiterpenoids from Streptomyces clavuligerus

• Dongxu Zhang,
• Wenyu Du,
• Xingming Pan,
• Xiaoxu Lin,
• Fang-Ru Li,
• Qingling Wang,
• Qian Yang,
• Hui-Min Xu and
• Liao-Bin Dong

Beilstein J. Org. Chem. 2024, 20, 815–822, doi:10.3762/bjoc.20.73

• mainly elucidated through comparative 1H and 13C NMR spectra and by comparing analytical data with existing literature reports [28][29] (see Supporting Information File 1, Figures S1–S7). The 1H NMR spectrum of compound 2 exhibited characteristic signals for one olefinic proton at δH (5.48) and four

• comparing the 1H and 13C NMR data with the literature (Figures S11 and S12 in Supporting Information File 1) [41]. Although the chemical structure of compound 8 has been documented, its 1H and 13C NMR data were not fully reported [42]. Therefore, we conducted comprehensive 1D and 2D NMR experiments on it

• differences in 13C NMR (ΔδC = 3.3) (Figures S19–S25, Supporting Information File 1) [43]. Moreover, the key correlation observed between H5 and H7 in the ROESY spectrum provides additional support for the β-configuration of this hydroxy group (Figure S26 and Table S7 in Supporting Information File 1). These

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

• most other solvents. C60–oligo-Lys and C60–oligo-Glu were characterized by 1H and 13C NMR. Photoinduced 1O2 generation was observed in the most soluble C60–oligo-Lys conjugate under visible light irradiation (527 nm) to show the potential of this highly water-soluble molecule in biological systems, for

• part (α, β, γ, δ, and ε). The observed splitting of the protons a and b was presumably due to a diastereotopic effect of the methine proton c, similar to the spectrum of the monoadduct. Figure 6a shows the 13C NMR spectra of 5a in D2O and of the monoadduct in CDCl3. Together with the 1H NMR, COSY, HSQC

• –peptide conjugate 5a in D2O (above) and of the precursor monoadduct in CDCl3 (bottom) at 600 MHz. 13C NMR spectrum of C60–peptide conjugate 5a in D2O and of the precursor monoadduct in CDCl3 at 150 MHz (a) and expansion of the sp2 carbon region (b). The asterisks in (a) correspond to a TFA impurity

Substrate specificity of a ketosynthase domain involved in bacillaene biosynthesis

• Zhiyong Yin and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2024, 20, 734–740, doi:10.3762/bjoc.20.67

• glutamate decarboxylase, and incubated with BaeJ-KS2. Substrate binding was demonstrated through 13C NMR analysis of the products against the background of various control experiments. Keywords: bacillaene; biosynthesis; enzyme mechanisms; isotopes; trans-AT polyketide synthases; Introduction Polyketides

• conjunction with 13C NMR to investigate substrate acceptance by BaeJ-KS2 from module 4 of the bacillaene PKS. Results and Discussion Synthesis of N-acetylcysteamine thioesters Previous studies have shown that N-acetylcysteamine thioesters (SNAC esters) can be uploaded to KS domains [22][23][24][25]. Therefore

• performed to eliminate any unreacted free 11 in the reaction mixture. The resulting protein preparations were subsequently analysed by 13C NMR spectroscopy. While the signal for the thioester carbonyl group of free 11 dissolved in incubation buffer was observed at δ = 203.33 ppm (Figure 1A), for both

Genome mining of labdane-related diterpenoids: Discovery of the two-enzyme pathway leading to (−)-sandaracopimaradiene in the fungus Arthrinium sacchari

• Fumito Sato,
• Terutaka Sonohara,
• Shunta Fujiki,
• Akihiro Sugawara,
• Yohei Morishita,
• Taro Ozaki and
• Teigo Asai

Beilstein J. Org. Chem. 2024, 20, 714–720, doi:10.3762/bjoc.20.65

• HREIMS spectrum. The 1H and 13C NMR spectra of 1 were identical to those of sandaracopimaradiene [30][31]. As the specific rotation of compound 1 was in good agreement with the reported data ([α]D24 −14.3 (c 0.97, CHCl3) in this study; [α]D25 −10.29 (c 0.65, CHCl3) in the literature [31]), compound 1 was

New variochelins from soil-isolated Variovorax sp. H002

• Jabal Rahmat Haedar,
• Aya Yoshimura and
• Toshiyuki Wakimoto

Beilstein J. Org. Chem. 2024, 20, 692–700, doi:10.3762/bjoc.20.63

• from 1. The 1H NMR spectrum showed additional olefinic proton signals at δH 5.35, as compared with that of 1. In line with this, two sp2 carbon signals at δC 130.6 and 131.0 were detected in the 13C NMR spectrum, demonstrating the presence of an olefin in 4. The comparative analysis of the MS/MS

• phase for 30 minutes to yield variochelins A (1, 10.0 mg), B (2, 20.1 mg), C (3, 3.0 mg), D (4, 2.1 mg), and E (5, 5.3 mg). Variochelin A (1) HRESIMS m/z: [M − 2H]2−, calcd for C47H83O17N11, 535.7911; found, 535.7912, Δ 0.2 ppm for C47H83O17N11; −7.5, (c 1.78, MeOH), 1H and 13C NMR chemical shifts see

• Table S1 (Supporting Information File 1). Variochelin B (2) HRESIMS m/z: [M − H]− calcd for C49H87O17N11, 1100.6209; found, 1100.6218, Δ 0.8 ppm for; C49H87O17N11; −11.1, (c 0.23, MeOH), 1H and 13C NMR chemical shifts see Table S1 (Supporting Information File 1). Variochelin C (3) HRESIMS m/z: [M − H

Evaluation of the enantioselectivity of new chiral ligands based on imidazolidin-4-one derivatives

• Jan Bartáček,
• Karel Chlumský,
• Jan Mrkvička,
• Lucie Paloušová,
• Miloš Sedlák and
• Pavel Drabina

Beilstein J. Org. Chem. 2024, 20, 684–691, doi:10.3762/bjoc.20.62

• catalysed by copper(II) complex of ligand IV. Asymmetric aldol reactions of various aldehydes with ketones catalysed by compound IV. Supporting Information Supporting Information File 62: General information and experimental data of prepared compounds, copies of 1H and 13C NMR spectra and DFT calculations