A novel bis-triazole scaffold accessed via two tandem [3 + 2] cycloaddition events including an uncatalyzed, room temperature azide–alkyne click reaction

• Ksenia Malkova,
• Andrey Bubyrev,
• Vasilisa Krivovicheva,
• Dmitry Dar’in,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1636–1641, doi:10.3762/bjoc.18.175

• Materials Research, and the Center for X-ray Diffraction Methods of Saint Petersburg State University Research Park for obtaining the analytical data. Funding This research was supported by the Megagrant of the Government of Russian Federation (# 075-15-2021-637).

A facile approach to spiro[dihydrofuran-2,3'-oxindoles] via formal [4 + 1] annulation reaction of fused 1H-pyrrole-2,3-diones with diazooxindoles

• Pavel A. Topanov,
• Anna A. Maslivets,
• Maksim V. Dmitriev,
• Irina V. Mashevskaya,
• Yurii V. Shklyaev and
• Andrey N. Maslivets

Beilstein J. Org. Chem. 2022, 18, 1532–1538, doi:10.3762/bjoc.18.162

• . Suvorova and Evgeniy P. Naimushin for providing technical help in the preparation of this article. Funding This work was supported by the Perm Research and Educational Center “Rational subsoil use” (2022), X-ray diffraction and spectral analyses were performed under financial support by the Ministry of

Comparison of crystal structure and DFT calculations of triferrocenyl trithiophosphite’s conformance

• Ruslan P. Shekurov,
• Mikhail N. Khrizanforov,
• Ilya A. Bezkishko,
• Tatiana P. Gerasimova,
• Almaz A. Zagidullin,
• Daut R. Islamov and
• Vasili A. Miluykov

Beilstein J. Org. Chem. 2022, 18, 1499–1504, doi:10.3762/bjoc.18.157

• orientations towards the phosphorus lone electron pair (LEP). A comparison of DFT calculations and X-ray diffraction data is presented, herein we show which conformations are preferred for a given ligand. Keywords: DFT calculations; multi-ferrocenyl compounds; phosphorus thioesters; trithiophosphite; X-ray

• . Trithiophosphite has not been studied by X-ray diffraction analysis, although it is of great interest for the construction of complexes with multiferrocene systems. Herein we present for the first time X-ray diffraction data of (FcS)3P and compare it with DFT calculations to show which conformation are preferred

• vacuo. The product was extracted with benzene (3 × 30 mL) and after evaporation of the solvent triferrocenyl trithiophosphite (1.34 g, 76%) was obtained as a yellow powder. Single crystals suitable for X-ray diffraction were obtained by dissolving the compound in a mixture of benzene/hexane 1:1 and

1,4,6,10-Tetraazaadamantanes (TAADs) with N-amino groups: synthesis and formation of boron chelates and host–guest complexes

• Artem N. Semakin,
• Ivan S. Golovanov,
• Yulia V. Nelyubina and
• Alexey Yu. Sukhorukov

Beilstein J. Org. Chem. 2022, 18, 1424–1434, doi:10.3762/bjoc.18.148

• stable than the corresponding hydrochloride salts, which slowly decompose upon storage at rt. The structures of products 19e·3HCl, 21 and its hydrochloride 21·HCl were confirmed by X-ray diffraction analysis (vide infra). In hydrochloride salts, the primary amino groups were protonated. In most cases

• 4a·H2O·0.5MeOH, 4a·HCl·H2O·MeOH, 4c·HCl·3.5MeOH, 8a, 21·HCl·2H2O, and hydrazinium dihydrochloride. Funding This work was supported by the Russian Foundation for Basic Research (grant 20-03-00510_a). X-ray diffraction data for Bn-4c(bromide)·3CD3OD, 19e·3HCl·H2O, and 21·2D2O were collected with financial

Synthesis of C6-modified mannose 1-phosphates and evaluation of derived sugar nucleotides against GDP-mannose dehydrogenase

• Sanaz Ahmadipour,
• Alice J. C. Wahart,
• Jonathan P. Dolan,
• Laura Beswick,
• Chris S. Hawes,
• Robert A. Field and
• Gavin J. Miller

Beilstein J. Org. Chem. 2022, 18, 1379–1384, doi:10.3762/bjoc.18.142

• minimum volume of hot EtOH, enabling solid state analysis (Figure 2). Crystals of 16 were analysed by single crystal X-ray diffraction and the data were solved in the monoclinic space group P21. Although the crystals suffered from intrinsic non-merohedral twinning through a non-crystallographic rotation

Mechanochemical bottom-up synthesis of phosphorus-linked, heptazine-based carbon nitrides using sodium phosphide

• Blaine G. Fiss,
• Georgia Douglas,
• Michael Ferguson,
• Jorge Becerra,
• Jesus Valdez,
• Trong-On Do,
• Tomislav Friščić and
• Audrey Moores

Beilstein J. Org. Chem. 2022, 18, 1203–1209, doi:10.3762/bjoc.18.125

• , mechanochemical synthesis of phosphorus-bridged heptazine-based carbon nitrides (g-h-PCN). The structure of these materials was determined through a combination of powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), 31P magic angle spinning nuclear magnetic resonance (MAS NMR), density

• argon gas, affording the material designated g-h-PCN300. Powder X-ray diffraction (PXRD) To confirm the formation of a layered structure, powder X-ray diffraction (PXRD) was performed on g-h-PCN and g-h-PCN300 (Figure 1, green and teal). Both g-h-PCN and g-h-PCN300 were largely amorphous but showed two

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

• derivatives present in the enamine form and stabilized by intramolecular hydrogen bonds (Table 5). Single-crystal X-ray diffraction confirmed the structure of 10aa (Figure 3) as well as the presence of the intramolecular N15–H15···O13 hydrogen bond [N15–H15: 0.92(3) Å, H15···O13: 1.90(3) Å, N15···O13: 2.699(3

Facile and diastereoselective arylation of the privileged 1,4-dihydroisoquinolin-3(2H)-one scaffold

• Dmitry Dar’in,
• Grigory Kantin,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1070–1078, doi:10.3762/bjoc.18.109

• , synthetic procedures, analytical data and NMR spectra for the reported compounds. Acknowledgements We thank the Research Center for Magnetic Resonance, the Center for Chemical Analysis and Materials Research, and the Center for X-ray Diffraction Methods of Saint Petersburg State University Research Park

Molecular diversity of the base-promoted reaction of phenacylmalononitriles with dialkyl but-2-ynedioates

• Hui Zheng,
• Ying Han,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2022, 18, 991–998, doi:10.3762/bjoc.18.99

• displayed a singlet at 3.52 ppm for the hydroxy group and two singlets at 3.24, 3.96 ppm with J = 14.8 Hz for the two diastereotopic protons of the cyclic methylene unit. The single crystal structure of compound 3k was successfully determined by X-ray diffraction analysis (Figure 1). From Figure 1, it can

• the reaction was carried out in weak basic solution (Supporting Information File 1) and its single crystal structure was determined by X-ray diffraction (Figure 4). When DABCO was used as a base, the further addition of the alkoxide ion to the cyano group in cis-position of the cyclopentyl ring

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

• -dependent density functional theory/electronic circular dichroism (TDDFT-ECD) calculations or X-ray diffraction analysis. A plausible biosynthetic pathway of these sesquiterpenoids and their internal correlation were proposed and discussed. In an in vitro bioassay, (+)-aristolone (3) exhibited promising

• reported in the literature. In addition, the full structure of 2, which was previously isolated from the soft coral Sinularia mayi [12], was unambiguously confirmed by X-ray diffraction analysis using Cu Kα radiation (λ = 1.54178 Å) [Flack parameter: 0.00 (11)] (Figure 2), since it was crystallized from

• worth determining their absolute configuration. Unfortunately, our efforts to obtain suitable crystals for X-ray diffraction analysis were unsuccessful. The lack of secondary hydroxy groups in these molecules prevented the use of chemical approaches. In addition, their weak Cotton effects (Figure 5

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

• ) after coupling and TFA-mediated Boc removal. Structural characterization of N-methylamino peptoid oligomers X-ray diffraction analysis of peptoid dimer 2 Peptoid dimer 2 was crystallized by slow evaporation from chloroform, and its high resolution structure was determined by X-ray crystallography. The

• NH groups (labeled H10 and H11, Figure 3C). The φ and ψ dihedral angle values are comparable to those measured by X-ray diffraction of monomers bearing benzylamino side chains [40], and of an N-aryl [33] and N-hydroxy peptoid dimers [36]. The latter dimer with φ angles of opposite sign was shown to

• from NMR and X-ray diffraction experimental data (Figure S3 in Supporting Information File 1). To understand how the methylamino-substituent will be oriented on oligo-NNMe peptoids, we have also performed a χ1 angle relaxed PES scan of acetyl-N-methylaminoglycine-dimethylamide (Figure S4 in Supporting

Copper-catalyzed multicomponent reactions for the efficient synthesis of diverse spirotetrahydrocarbazoles

• Shao-Cong Zhan,
• Ren-Jie Fang,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2022, 18, 796–808, doi:10.3762/bjoc.18.80

• compound 3a (CCDC 2109578) and 4e (CCDC 2109579) were successfully determined by X-ray diffraction. It is pleased to find that the obtained spiro[carbazole-3,5'-pyrimidines] 4a–h have same cis-configuration to that of the above prepared spiro[carbazole-3,3'-indolines] 1a–j and spiro[carbazole-2,3

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

• made use of resources from the X-ray Diffraction Center, Computer Center, Center for Magnetic Resonance, Educational Resource Center of Chemistry, Center for Chemical Analysis and Materials of Saint-Petersburg State University. Funding We gratefully acknowledge the financial support from the Russian

An isoxazole strategy for the synthesis of 4-oxo-1,4-dihydropyridine-3-carboxylates

• Timur O. Zanakhov,
• Ekaterina E. Galenko,
• Mikhail S. Novikov and
• Alexander F. Khlebnikov

Beilstein J. Org. Chem. 2022, 18, 738–745, doi:10.3762/bjoc.18.74

• . According to the calculation results compounds 2 exist in the pyridone form in acetonitrile or chloroform solution (Table 1). All new compounds were characterized by 1H, 13C NMR and HRMS methods. Moreover, the structure of 2k was also confirmed by single-crystal X-ray diffraction analysis (Figure S1

• File 179: Experimental procedures, compound characterization data, X-ray diffraction experiment, and copies of NMR spectra of new compounds. Supporting Information File 180: Crystallographic information file for compound 2k. Funding We gratefully acknowledge the financial support of the Russian

• Science Foundation project 21-73-00019. This research was carried out using resources of the Centre for Magnetic Resonance, the Research Centre for X-ray Diffraction Studies, the Centre for Chemical Analysis and Materials, and the Computer Centre of the Science Park of Saint Petersburg State University.

Mechanochemical halogenation of unsymmetrically substituted azobenzenes

• Dajana Barišić,
• Mario Pajić,
• Ivan Halasz,
• Darko Babić and
• Manda Ćurić

Beilstein J. Org. Chem. 2022, 18, 680–687, doi:10.3762/bjoc.18.69

• from laboratory powder X-ray diffraction (PXRD) data (Figure 4 and Figures S31 and S32 in Supporting Information File 1), are similar to that of complex I1-I [51] in which the palladium center is bound to the MeCN and tosylate (OTs) via nitrogen and oxygen, respectively, and to the azobenzene via the

Tri(n-butyl)phosphine-promoted domino reaction for the efficient construction of spiro[cyclohexane-1,3'-indolines] and spiro[indoline-3,2'-furan-3',3''-indolines]

• Hui Zheng,
• Ying Han,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2022, 18, 669–679, doi:10.3762/bjoc.18.68

• major isomers 3l (Figure 1), 3s (Figure 2), and 3f’ (Figure 3) were determined by X-ray diffraction analysis. As can be seen from Figure 1 and Figure 2, the aryl group exists in the trans-position of the carbonyl group of the oxindole scaffold in the newly formed cyclohexyl ring. On the other hand, the

• compound 8a (Figure 5) was determined by X-ray diffraction analysis. From Figure 5, it can be seen that the two oxindole moieties exist on the trans-configuration. Therefore, this reaction showed very high diastereoselectivity. To explain the formation of the dispiro compounds 8, a plausible reaction

• are summarized in Table 3. Because there are three chiral carbon atoms in the molecule, several diastereoisomers can be formed in the reaction. The spiro[cyclohexane-1,3'-indolines] 5a–e were obtained in moderate to good yields. The single crystal structure of compound 5a was determined by X-ray

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

• established by X-ray diffraction. Keywords: allomaltol; ESIPT process; photochemistry; pyrazoles; terarylenes; Introduction The investigation of the photochemical behavior of organic products is a significant part of modern materials science and technology. The UV-induced processes are extensively employed

• corresponding quinoxalines 15a–l in good yields (Scheme 5). The structure of 15a was confirmed by single-crystal X-ray diffraction (Figure 2) as a representative example. It should be noted that X-ray analysis of the final quinoxaline unambiguously proves the conversion of the allomaltol fragment into the

• good yields (Scheme 6). The structure of 15m was confirmed by single-crystal X-ray diffraction (Figure 3). It should be mentioned that other options for trapping of photogenerated unstable α-hydroxy-1,2-diketones are also possible. For example, reduction via NaBH3CN can be used as an alternative

Unusual highly diastereoselective Rh(II)-catalyzed dimerization of 3-diazo-2-arylidenesuccinimides provides access to a new dibenzazulene scaffold

• Anastasia Vepreva,
• Alexander S. Bunev,
• Andrey Yu. Kudinov,
• Grigory Kantin,
• Mikhail Krasavin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2022, 18, 533–538, doi:10.3762/bjoc.18.55

• Resonance, the Center for Chemical Analysis and Materials Research and the Center for X-ray Diffraction Methods of Saint Petersburg State University Research Park for obtaining the analytical data. Funding This research was supported by the Russian Science Foundation (project grant 20-13-00024).

Tosylhydrazine-promoted self-conjugate reduction–Michael/aldol reaction of 3-phenacylideneoxindoles towards dispirocyclopentanebisoxindole derivatives

• Sayan Pramanik and
• Chhanda Mukhopadhyay

Beilstein J. Org. Chem. 2022, 18, 469–478, doi:10.3762/bjoc.18.49

• each product, but the single crystal X-ray diffraction analysis confirmed the diastereoselectivity of 3. A single crystal of 3g was successfully obtained by slow evaporation of the solvent with the structure unequivocally confirmed by X-ray diffraction analysis (Figure 2). The single crystal X-ray

• diffraction analysis also revealed the presence of four chiral stereocenters with two oxindole moieties at 1,3-possition that are in trans orientation to the 2-benzoyl group and the 5-aryl group is in cis orientation (Figure 2). This observation proved that the most thermodynamically stable diastereomer was

Four bioactive new steroids from the soft coral Lobophytum pauciflorum collected in South China Sea

• Di Zhang,
• Zhe Wang,
• Xiao Han,
• Xiao-Lei Li,
• Zhong-Yu Lu,
• Bei-Bei Dou,
• Wen-Ze Zhang,
• Xu-Li Tang,
• Ping-Lin Li and
• Guo-Qiang Li

Beilstein J. Org. Chem. 2022, 18, 374–380, doi:10.3762/bjoc.18.42

• structurally related compounds reported in the literature. The absolute configuration of 1–3 was determined by X-ray diffraction. All the compounds have assessed the cytotoxicity against HL-60, K562, and Hela cells. Compound 1 showed weak cytotoxicity against K562 cells with an IC50 value of 19.03 μM. In

• addition, compound 1 also showed a moderate anti-inflammatory effect in zebrafish. Keywords: anti-inflammatory; cytotoxicity; Lobophytum pauciflorum; soft coral; steroids; X-ray diffraction; Introduction The unique and complicated marine environment makes soft corals a treasure-house of secondary

• NOESY correlations of H3-18 with H3-21 suggested the E geometry of Δ17(20). Finally, the absolute configuration of compound 1 was established by single-crystal X-ray diffraction analysis (Figure 4) carried out using Cu Kα radiation with a Flack parameter of 0.0(2). Compound 2, was isolated as a white

Unexpected chiral vicinal tetrasubstituted diamines via borylcopper-mediated homocoupling of isatin imines

• Marco Manenti,
• Leonardo Lo Presti,
• Giorgio Molteni and
• Alessandra Silvani

Beilstein J. Org. Chem. 2022, 18, 303–308, doi:10.3762/bjoc.18.34

• diastereoselectivity of the reaction (see Supporting Information File 1). All stereochemical implications were fully confirmed by single-crystal X-ray diffraction analysis, which was performed on well-formed prismatic crystals of compound 2a (Figure 1) [28]. Compound 2a is chiral and crystallizes in the orthorhombic

• determined by single-crystal X-ray diffraction analysis. Conclusion In summary, we have disclosed a reaction protocol that allows efficient homocoupling of oxindole-based N-tert-butanesulfinyl imines and generation of chiral, quaternary 1,2-diamines in a mild and completely stereoselective way. The one-pot

• products we disclosed the efficient homocoupling of oxindole-based N-tert-butanesulfinyl imines, with the generation of chiral, quaternary 1,2-diamines in a mild and completely stereoselective way. The obtained 3,3′-bisoxindole derivatives were fully characterized by NMR and single-crystal X-ray

Multi-faceted reactivity of N-fluorobenzenesulfonimide (NFSI) under mechanochemical conditions: fluorination, fluorodemethylation, sulfonylation, and amidation reactions

• José G. Hernández,
• Karen J. Ardila-Fierro,
• Dajana Barišić and
• Hervé Geneste

Beilstein J. Org. Chem. 2022, 18, 182–189, doi:10.3762/bjoc.18.20

• '' “remain[ed] obscure” [28]. In our case, we anticipated that formation of 2c'' could be accompanied by concomitant formation of (PhSO2)2NH and (PhSO2)2NCH3 derived from NFSI and 1c. For the analysis of the reaction mixture we selected powder X-ray diffraction (PXRD), a rapid analytical technique that has

• %; (SO2Ph)2NCH3 yield = 82%. (b) Powder X-ray diffraction (PXRD) patterns measured for the reactants and simulated PXRD patterns for the published (SO2Ph)2NCH3 (CCDC ZAJBIZ) and (SO2Ph)2NH (CCDC BSULFA). (c) 1H NMR analysis of the reaction mixture of the milling of 1c and NFSI (2.0 equiv) at 30 Hz for 3 h

Ready access to 7,8-dihydroindolo[2,3-d][1]benzazepine-6(5H)-one scaffold and analogues via early-stage Fischer ring-closure reaction

• Irina Kuznetcova,
• Felix Bacher,
• Daniel Vegh,
• Hsiang-Yu Chuang and
• Vladimir B. Arion

Beilstein J. Org. Chem. 2022, 18, 143–151, doi:10.3762/bjoc.18.15

• , characterization data and 1H and 13C NMR spectra of compounds, NMR numbering schemes and X-ray crystallography data. Acknowledgements We also thank Mr. Alexander Roller and Ms. Natalie Gajic for collection of X-ray diffraction data. Funding Support from the Austrian Science Fund (FWF) (P31293-N37) and Slovak

Green synthesis of C5–C6-unsubstituted 1,4-DHP scaffolds using an efficient Ni–chitosan nanocatalyst under ultrasonic conditions

• Soumyadip Basu,
• Sauvik Chatterjee,
• Suman Ray,
• Suvendu Maity,
• Prasanta Ghosh,
• Asim Bhaumik and
• Chhanda Mukhopadhyay

Beilstein J. Org. Chem. 2022, 18, 133–142, doi:10.3762/bjoc.18.14

• characterized by powder Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray (EDX) spectroscopy, etc. It was effectively utilized in the eco-friendly synthesis of

Regioselective synthesis of methyl 5-(N-Boc-cycloaminyl)-1,2-oxazole-4-carboxylates as new amino acid-like building blocks

• Jolita Bruzgulienė,
• Greta Račkauskienė,
• Aurimas Bieliauskas,
• Vaida Milišiūnaitė,
• Miglė Dagilienė,
• Gita Matulevičiūtė,
• Vytas Martynaitis,
• Sonata Krikštolaitytė,
• Frank A. Sløk and
• Algirdas Šačkus

Beilstein J. Org. Chem. 2022, 18, 102–109, doi:10.3762/bjoc.18.11

• analysis, 1H, 13C, and 15N NMR spectroscopy, HRMS, and single-crystal X-ray diffraction data. Keywords: β-enamino ketoesters; heterocyclic amino acids; 15N-labeled 1,2-oxazole; NMR (1H; 13C; 15N); 1,2-oxazole (isoxazole); X-ray structure analysis; Introduction 1,2-Oxazoles (isoxazoles) constitute an

• and 4g with trifluoroacetic acid. Removal of the Boc protection in the presence of CF3COOH in dichloromethane yielded trifluoroacetates 6a and 6b as white solids (Scheme 4). A single crystal of 6b was prepared via recrystallization from dichloromethane for X-ray diffraction analysis [48]. The