Preparation of β-cyclodextrin-based dimers with selectively methylated rims and their use for solubilization of tetracene

• Konstantin Lebedinskiy,
• Volodymyr Lobaz and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2022, 18, 1596–1606, doi:10.3762/bjoc.18.170

• with Thermo Scientific Helios γ with wolfram and deuterium lamp. The wavelength range is 190–800 nm. 1H, 13C, and 2D NMR spectra were measured on Bruker Avance III HD 400 spectrometer. For TLC detection of CDs, we charred a TLC plate with 50% sulfuric acid water solution at 250 °C. UV measurements The

• binding calculated from ITC experiments. Supporting Information Supporting Information File 326: Synthetic procedures, characterization, 1H, 13C DEPT, 2D NMR, IR, UV–vis spectra of synthesized compounds; UV–vis spectra of tetracene solutions in DMSO; ITC thermograms. Funding This work has been supported

Efficient synthesis of aziridinecyclooctanediol and 3-aminocyclooctanetriol

• Emine Salamci and
• Ayse Kilic Lafzi

Beilstein J. Org. Chem. 2022, 18, 1539–1543, doi:10.3762/bjoc.18.163

• )cyclooctene 6 in 70% yield (Scheme 1). Oxidation of the dibenzylated compound 6 with OsO4/NMO provided the corresponding diol 7 in 90% yield. The exact configuration of 7 was confirmed by 1H and 2D NMR spectroscopic data. Next, mesylation of the hydroxy groups in 7 with MsCl in pyridine yielded dimesylate 8

• NMR spectra for all new compounds, as well as selected 2D NMR spectra are provided. Acknowledgements We would like to thank Baris Anil for performing the 2D NMR spectroscopy. Funding The authors are indebted to the Scientific and Technological Research Council of Turkey (TUBITAK, Grant No. TBAG

Sinensiols H–J, three new lignan derivatives from Selaginella sinensis (Desv.) Spring

• Qinfeng Zhu,
• Beibei Gao,
• Qian Chen,
• Tiantian Luo,
• Guobo Xu and
• Shanggao Liao

Beilstein J. Org. Chem. 2022, 18, 1410–1415, doi:10.3762/bjoc.18.146

• basis of 1D and 2D NMR spectroscopy as well as high-resolution mass spectrometry. The absolute configuration of 1 was established by ECD calculation. Compounds 2 and 3 represent rare examples of naturally occurring 9,9'-bisnorlignans. All the isolated compounds were assayed for their inhibitory effects

Cyclodextrin-based Schiff base pro-fragrances: Synthesis and release studies

• Attila Palágyi,
• Jindřich Jindřich,
• Juraj Dian and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2022, 18, 1346–1354, doi:10.3762/bjoc.18.140

• the system. Sustained release of the aldehyde was demonstrated both in aqueous solutions and from a solid state upon humidity exposure. Experimental Instruments, general methods, and chemicals 1H NMR, 13C NMR, 2D NMR (H,H-COSY, HSQC, and HMBC) were measured on Bruker AVANCE III 600 MHz (600.17 MHz for

Experimental and theoretical studies on the synthesis of 1,4,5-trisubstituted pyrrolidine-2,3-diones

• Nguyen Tran Nguyen,
• Vo Viet Dai,
• Nguyen Ngoc Tri,
• Luc Van Meervelt,
• Nguyen Tien Trung and
• Wim Dehaen

Beilstein J. Org. Chem. 2022, 18, 1140–1153, doi:10.3762/bjoc.18.118

• observed. In addition, the methylene protons are diastereotopic and they show geminal coupling. As a consequence, the two methylene protons were observed as two doublets of doublets at 4.40 ppm and 4.49 ppm, respectively. Moreover, the HMBC 2D NMR spectrum of compound 10aa also exhibited the correlation

New azodyrecins identified by a genome mining-directed reactivity-based screening

• Atina Rizkiya Choirunnisa,
• Kuga Arima,
• Yo Abe,
• Noritaka Kagaya,
• Kei Kudo,
• Hikaru Suenaga,
• Junko Hashimoto,
• Manabu Fujie,
• Noriyuki Satoh,
• Kazuo Shin-ya,
• Kenichi Matsuda and
• Toshiyuki Wakimoto

Beilstein J. Org. Chem. 2022, 18, 1017–1025, doi:10.3762/bjoc.18.102

• series of 2D NMR analyses and optical rotation revealed that six of the isolated compounds are azodyrecin A (1), azodyrecin B (2), azodyrecin C (3), and their geometric isomers 1’-trans-azodyrecin A (4), 1’-trans-azodyrecin B (5), and 1’-trans-azodyrecin C (6), respectively, which were previously

• , together with 2D NMR spectra showed that compounds 8, 9, and 10 were azodyrecin derivatives with saturated alkyl side chains, which were named azodyrecin E (8), azodyrecin F (9), and azodyrecin G (10), respectively (Figure S3, Supporting Information File 1). Although azodyrecins characteristically possess

• –G (7–10) (b). Key correlations in 2D NMR are shown. In vitro characterization of Ady1. Extracted ion chromatograms at m/z 329.3 (black) and m/z 343.3 (blue), corresponding to compound 11 and 8, respectively, are shown. Sequence similarity network of VlmA-like enzymes in the actinobacterial genomes

Isolation and biosynthesis of daturamycins from Streptomyces sp. KIB-H1544

• Yin Chen,
• Jinqiu Ren,
• Ruimin Yang,
• Jie Li,
• Sheng-Xiong Huang and
• Yijun Yan

Beilstein J. Org. Chem. 2022, 18, 1009–1016, doi:10.3762/bjoc.18.101

• . The supernatant was analyzed by HPLC. Structures of compounds 1–6, atromentin, and echoside C. (A) Key 2D NMR correlations of compounds 1 and 2. (B) X-ray crystal structure of compounds 1 and 3. (A) The biosynthetic gene cluster of daturamycins. (B) Proposed biosynthetic pathway of daturamycins. (A

Anti-inflammatory aromadendrane- and cadinane-type sesquiterpenoids from the South China Sea sponge Acanthella cavernosa

• Shou-Mao Shen,
• Qing Yang,
• Yi Zang,
• Jia Li,
• Xueting Liu and
• Yue-Wei Guo

Beilstein J. Org. Chem. 2022, 18, 916–925, doi:10.3762/bjoc.18.91

• (+)-1 also being an aromadendrane-type sesquiterpenoid containing a gem-dimethylcyclopropyl unit [δH 0.80 (dd, J = 10.6, 9.6 Hz, H-6), 0.68 (m, H-7), 1.07 (s, 12-Me), 1.19 (s, 13-Me)]. Further literature survey revealed that the overall 1D and 2D NMR data of compound (+)-1 (Table 1), except the optical

• with 4. The IR absorption band at 3386 cm−1 suggested the presence of hydroxy groups. A careful analysis of its 1D and 2D NMR spectra revealed that the NMR spectroscopic features of compound 5 (Table 1 and Figures S24–S31 in Supporting Information File 1) extremely resembled those of 4. The main

First series of N-alkylamino peptoid homooligomers: solution phase synthesis and conformational investigation

• Maxime Pypec,
• Laurent Jouffret,
• Claude Taillefumier and
• Olivier Roy

Beilstein J. Org. Chem. 2022, 18, 845–854, doi:10.3762/bjoc.18.85

• -(alkylamino)glycine units is investigated. We demonstrate that N-(methylamino)glycine homooligomers can be readily synthesized in solution using N-Boc-N-methylhydrazine as a peptoid submonomer and stepwise or segment coupling methodologies. Their structures were analyzed in solution by 1D and 2D NMR, in the

Synthesis of bis-spirocyclic derivatives of 3-azabicyclo[3.1.0]hexane via cyclopropene cycloadditions to the stable azomethine ylide derived from Ruhemann's purple

• Alexander S. Filatov,
• Olesya V. Khoroshilova,
• Anna G. Larina,
• Vitali M. Boitsov and
• Alexander V. Stepakov

Beilstein J. Org. Chem. 2022, 18, 769–780, doi:10.3762/bjoc.18.77

• cycloadduct 4 were unequivocally established on the basis of its two-dimensional (2D) NMR spectrum (1H,1H nuclear Overhauser effect spectroscopy (NOESY), see Supporting Information File 1, Figures S17–S19). This experiment showed that azomethine ylide 1 also predominantly undergoes cycloaddition to the

Cholyl 1,3,4-oxadiazole hybrid compounds: design, synthesis and antimicrobial assessment

• Anas J. Rasras,
• Mohamed El-Naggar,
• Nesreen A. Safwat and
• Raed A. Al-Qawasmeh

Beilstein J. Org. Chem. 2022, 18, 631–638, doi:10.3762/bjoc.18.63

• quaternary oxadiazole peaks appeared at around δ = 162.0 and 169.0 ppm. Compound 4f showed a carbonyl peak at δ = 196.7 ppm and for the carbaldehyde carbon in compound 4h a peak at δ = 160.8 ppm was observed. To further characterize the structures, 2D NMR experiments were done for compound 4p as example. The

A study of the photochemical behavior of terarylenes containing allomaltol and pyrazole fragments

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

Beilstein J. Org. Chem. 2022, 18, 588–596, doi:10.3762/bjoc.18.61

• communication we have described for the first time the phototransformation of the 3-hydroxypyran-4-one fragment with the isolation of the resulting substituted α-hydroxy-1,2-diketone in pure form. The structure of the obtained compound 14a was confirmed using 1H, 13C NMR spectroscopy as well as 2D NMR

• : Experimental procedures, characterization data of all products, copies of 1H, 13C, 2D NMR, HRMS spectra of all new compounds, and X-ray crystallographic data.

Terpenoids from Glechoma hederacea var. longituba and their biological activities

• Dong Hyun Kim,
• Song Lim Ham,
• Zahra Khan,
• Sun Yeou Kim,
• Sang Un Choi,
• Chung Sub Kim and
• Kang Ro Lee

Beilstein J. Org. Chem. 2022, 18, 555–566, doi:10.3762/bjoc.18.58

• structure elucidation was performed for the five new compounds (1–5) using 1D and 2D NMR, HRESIMS, DP4+ and ECD calculations, and chemical methods. All the isolates (1–9) were assessed for their antineuroinflammatory activities on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV-2 cells

• compounds (1–5) were isolated and characterized from G. hederacea var. longituba (Figure 1). Structures of these compounds were established by 1D and 2D NMR and HRESIMS, comparison of experimental and calculated ECD data, DP4+ analysis, and hydrolysis. Herein, the isolation and structural elucidation of the

• of 2 were similar to those of substolide A except for signals of the methoxy group attached to C-8 and of a monosaccharide at C-6 in 2 [12]. The planar structure of 2 was established based on 2D NMR spectroscopic data (COSY, HSQC, and HMBC). The HMBC correlation from H-1' (δH 4.42) to C-6 (δC 76.6

Menadione: a platform and a target to valuable compounds synthesis

• Acácio S. de Souza,
• Ruan Carlos B. Ribeiro,
• Dora C. S. Costa,
• Fernanda P. Pauli,
• David R. Pinho,
• Matheus G. de Moraes,
• Fernando de C. da Silva,
• Luana da S. M. Forezi and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43

• menadione (10) in trifluoroacetic acid under ethanol reflux conditions (Scheme 26) to synthesize acylhydrazones 81 in 63–91% yield. In view of the different structures that compounds 81a–e could adopt, after analysis by 2D NMR-NOESY spectra, it was found that all products were obtained as E-geometrical

Amamistatins isolated from Nocardia altamirensis

• Till Steinmetz,
• Wolf Hiller and
• Markus Nett

Beilstein J. Org. Chem. 2022, 18, 360–367, doi:10.3762/bjoc.18.40

• Abstract Four new phenolic siderophores were isolated from the actinomycete Nocardia altamirensis along with the known natural product amamistatin B and a putative biosynthetic shunt product. The structures of all compounds were elucidated through 1D and 2D NMR analyses as well as mass spectrometry. The

• the basis of 2D NMR data. In the HMBC spectrum, the singlet methyl protons H3-17 and H3-18 show correlations to C-7, a quaternary carbon at 47.4 ppm (C-8), and an oxymethine carbon at 80.3 ppm (C-9). COSY and HMBC data established the alkyl chain from CH-9 to CH3-16. A correlation between H-9 and C-19

• C35H53N5O7 by the [M + H]+ ion at m/z 656.4019 (calcd for C35H54N5O7, 656.4023). Analysis of 1D and 2D NMR spectra confirmed that the aldehyde group in position 25 is missing. Therefore, compound 3 represents the N-desformyl analogue of 1. Compound 4 (1.9 mg) was obtained as a reddish oil. Its molecular

Glycosylated coumarins, flavonoids, lignans and phenylpropanoids from Wikstroemia nutans and their biological activities

• Meifang Wu,
• Xiangdong Su,
• Yichuang Wu,
• Yuanjing Luo,
• Ying Guo and
• Yongbo Xue

Beilstein J. Org. Chem. 2022, 18, 200–207, doi:10.3762/bjoc.18.23

• including its absolute configuration was elucidated based on a combination of 1D and 2D NMR, UV, IR, HRESIMS spectroscopic data, as well as chemical transformation. Compounds 1–17 were first isolated from the plant species W. nutans, while compounds 1–3, 8, and 11 were reported from the genus Wikstroemia

• structures were established by extensive spectroscopic analyses, including 1D, 2D NMR spectroscopy, and HRESIMS. The relative and absolute structure of 1 was unambiguously determined based on ROESY experiments and chemical transformation. In the vitro bioassays, compounds 1–17 showed a mild inhibitory effect

• samples were scanned from 190 to 400 nm in 1 nm steps. IR spectra were obtained using a Tensor 27 spectrophotometer with KBr pellets. 1D and 2D NMR spectra were acquired on Bruker DRX-600 and DRX-800 spectrometers with TMS as internal standard. Chemical shifts (δ) were expressed in ppm with reference to

Tenacibactins K–M, cytotoxic siderophores from a coral-associated gliding bacterium of the genus Tenacibaculum

• Yasuhiro Igarashi,
• Yiwei Ge,
• Tao Zhou,
• Amit Raj Sharma,
• Enjuro Harunari,
• Naoya Oku and
• Agus Trianto

Beilstein J. Org. Chem. 2022, 18, 110–119, doi:10.3762/bjoc.18.12

• while only a single set experiment was possible for 2 due to its limited availability. Structures of tenacibactins K–M (1–3). Key 2D-NMR correlations for 1–3. (a) Partial 1H NMR spectra of 1 at 25 and 50 °C in DMSO-d6; (b) magnified HMBC spectrum of 1 at 25 °C in CDCl3/CD3OD 3:7. MS/MS spectrum of 1

Efficient and regioselective synthesis of dihydroxy-substituted 2-aminocyclooctane-1-carboxylic acid and its bicyclic derivatives

• İlknur Polat,
• Selçuk Eşsiz,
• Uğur Bozkaya and
• Emine Salamci

Beilstein J. Org. Chem. 2022, 18, 77–85, doi:10.3762/bjoc.18.7

• -functional theory (DFT) computations were used to explain the reaction mechanism for the ring opening of the epoxide and the formation of five-membered lactones. The stereochemistry of the synthesized compounds was determined by 1D and 2D NMR spectroscopy. The configuration of methyl 6-hydroxy-9-oxo-8

• expected product 9 failed. The product 8 was obtained as the major product in 80% yield, and the expected product 9 was formed as the minor product in 4% yield. We propose that diol isomer mixture 9 can be formed by solvolysis. The presence of the lactone ring in 8 was determined by 2D NMR spectroscopic

• . However, all attempts to isolate isomer mixture 11 failed. Again, we suggest that diol isomer mixture 11 can be formed by solvolysis. The presence of the lactone ring in 10 was determined by 2D NMR spectroscopic data (COSY and HMQC). The diagonal peak at 4.19 ppm has cross peaks with the protons

Isolation and characterization of new phenolic siderophores with antimicrobial properties from Pseudomonas sp. UIAU-6B

• Emmanuel T. Oluwabusola,
• Olusoji O. Adebisi,
• Fernando Reyes,
• Kojo S. Acquah,
• Mercedes De La Cruz,
• Larry L. Mweetwa,
• Joy E. Rajakulendran,
• Digby F. Warner,
• Deng Hai,
• Rainer Ebel and
• Marcel Jaspars

Beilstein J. Org. Chem. 2021, 17, 2390–2398, doi:10.3762/bjoc.17.156

• from the Oyun river in North Central Nigeria. The structure of the new compounds, pseudomonin A–C (1–3) and pseudomobactin A and B (4 and 5) isolated alongside two known compounds, pseudomonine (6) and salicylic acid (7), were elucidated based on high-resolution mass spectrometry, 1D and 2D NMR

• secondary metabolites 1–5 including pseudomonin A–C (1–3) and pseudomobactins A and B (4 and 5). The two known compounds, pseudomonine (6) and salicylic acid (7) were also isolated as the major constituents of the extracts and their structures were determined by analysis of HRESIMS, 1D and 2D NMR data (see

• that revealed a molecular ion at m/z 237.0874 (calcd for C11H13N2O4−, 237.0880). A thorough analysis of 1H and 2D NMR data (see Table 1 and Supporting Information File 1) showed four aromatic methines, two aliphatic methines, one methyl, and four quaternary carbons signals at δC 162.9 (C-1), 113.2 (C-6

Phenolic constituents from twigs of Aleurites fordii and their biological activities

• Kyoung Jin Park,
• Won Se Suh,
• Da Hye Yoon,
• Chung Sub Kim,
• Sun Yeou Kim and
• Kang Ro Lee

Beilstein J. Org. Chem. 2021, 17, 2329–2339, doi:10.3762/bjoc.17.151

• absolute configuration. The planar structure of 3 was further confirmed by analysis of 2D NMR data, including COSY, HSQC, and HMBC (Figure 2). The determination of the stereochemistry for the sugar unit of 3 was conducted following the same method as for compound 2. The structure of the aglycone 3a

• and 13C NMR spectral data of 15 and 16 in CD3OD. Effects of isolated compounds on NO production in LPS-activated BV-2 cells. Effects of isolated compounds on NGF secretion in C6 cells. Supporting Information Supporting Information File 260: Copies of NMR spectra including 1D and 2D NMR and HRMS data

A study on selective transformation of norbornadiene into fluorinated cyclopentane-fused isoxazolines

• Zsanett Benke,
• Attila M. Remete and
• Loránd Kiss

Beilstein J. Org. Chem. 2021, 17, 2051–2066, doi:10.3762/bjoc.17.132

• catalyst-dependent (Table 1). In the presence of HG-2, the main product was dicoupled (±)-8c accompanied by the unseparable mixture of monocoupled products (±)-8a and (±)-8b. Despite the partial signal overlap, 2D NMR analysis of the (±)-8a and (±)-8b mixture was possible, and the structure of both (±)-8a

Analogs of the carotane antibiotic fulvoferruginin from submerged cultures of a Thai Marasmius sp.

• Birthe Sandargo,
• Leon Kaysan,
• Rémy B. Teponno,
• Christian Richter,
• Benjarong Thongbai,
• Frank Surup and
• Marc Stadler

Beilstein J. Org. Chem. 2021, 17, 1385–1391, doi:10.3762/bjoc.17.97

• antibiotic fulvoferruginin (1), fulvoferruginins B–F (2–6). The structures of these sesquiterpenoids were elucidated using HRESIMS, 1D and 2D NMR, as well as CD spectroscopy. Assessing the bioactivity, fulvoferruginin emerged as a potent cytotoxic agent of potential pharmaceutical interest. Keywords

• due to two methylenes at δC 38.8 (C-8) and 39.2 (C-9); three methines at δC 46.4 (C-11), 58.4 (C-6), and 77.6 (C-7) as well as two quaternary carbons at δC 45.6 (C-8) and 82.8 (C-10). Correlating 1D data with 2D NMR experiments (1H,1H COSY, 1H,13C HMBC, 1H,1H ROESY, see Figure 2) led to an underlying

• isolated and identified as fulvoferruginin (1), utilizing HRESIMS and 1D/2D NMR experiments (see Table S3 in Supporting Information File 1). The methyl group C-14 of fulvoferruginin B (2) results in an additional stereocenter at C-11. The proton at C-11 (δH 2.72) exhibited 1H,1H ROESY correlations with H-5

Synthesis of multiply fluorinated N-acetyl-D-glucosamine and D-galactosamine analogs via the corresponding deoxyfluorinated glucosazide and galactosazide phenyl thioglycosides

• Vojtěch Hamala,
• Lucie Červenková Šťastná,
• Martin Kurfiřt,
• Petra Cuřínová,
• Martin Dračínský and
• Jindřich Karban

Beilstein J. Org. Chem. 2021, 17, 1086–1095, doi:10.3762/bjoc.17.85

• conversion and debenzylation. The values [Hz] of selected coupling constants. Boldfaced values illustrate the trends discussed in the text. Supporting Information Supporting Information File 89: Experimental procedures and spectral data. Supporting Information File 90: Copies of 1H, 13C, 19F, and 2D NMR

Stereoselective synthesis and transformation of pinane-based 2-amino-1,3-diols

• Ákos Bajtel,
• Mounir Raji,
• Matti Haukka,
• Ferenc Fülöp and
• Zsolt Szakonyi

Beilstein J. Org. Chem. 2021, 17, 983–990, doi:10.3762/bjoc.17.80

• 9 ring system (Scheme 1). The absolute configuration of compound 9 was determined by 2D NMR spectroscopic techniques. Clear NOE signals were observed between the H-7a and Me-10 as well as the Ha-9 and Me-10 protons. Beside NOESY experiments, the structure was also elucidated by X-ray crystallography

• configuration depicted in Scheme 2. Beside 2D NMR spectroscopic studies, the absolute configuration of compound 12 was determined by its transformation into the corresponding aminodiols 13 and 14, comparing the products with those obtained from the regioisomer 9 (discussed in Scheme 3). Synthesis and

• of the five components 15A–E were determined by 2D NMR spectroscopic techniques (NOESY and HMBC). Since this finding is quite unusual in the case of Schiff’ bases, we decided to study the ring/chain tautomeric mixture (15A–E) in the reaction of 13 with benzaldehyde by 1H NMR spectroscopy. When a time

Total synthesis of pyrrolo[2,3-c]quinoline alkaloid: trigonoine B

• Takashi Nishiyama,
• Erina Hamada,
• Daishi Ishii,
• Yuuto Kihara,
• Nanase Choshi,
• Natsumi Nakanishi,
• Mari Murakami,
• Kimiko Taninaka,
• Noriyuki Hatae and
• Tominari Choshi

Beilstein J. Org. Chem. 2021, 17, 730–736, doi:10.3762/bjoc.17.62

• structures of the compounds were elucidated through 1D and 2D NMR spectroscopy. It was determined that trigonoine A was a β-carboline alkaloid containing a 2,8-diazabicyclo[3.3.1]nonane ring system, while trigonoine B (1) was formed by a combination of 2,3-dihydroquinolin-4-one and 3H-pyrrolo[2,3-c]quinoline