Tandem diazotization/cyclization approach for the synthesis of a fused 1,2,3-triazinone-furazan/furoxan heterocyclic system

• Yuri A. Sidunets,
• Valeriya G. Melekhina and
• Leonid L. Fershtat

Beilstein J. Org. Chem. 2024, 20, 2342–2348, doi:10.3762/bjoc.20.200

• , whether isolated or generated in situ, may undergo various controlled transformations [42]. However, previously, we failed to introduce amino-1,2,5-oxadiazoles bearing an amide functionality into the diazotization protocol, arguably due to an increased electron-withdrawing effect and elevated instability

• and straightforward approach for the synthesis of previously unknown [1,2,5]oxadiazolo[3,4-d][1,2,3]triazin-7(6H)-one derivatives based on tandem diazotization/azo coupling reactions of readily available (1,2,5-oxadiazolyl)carboxamides containing an amino functionality. The developed protocol was

• ). NO release data. Tandem diazotization/azo coupling reactions of (1,2,5-oxadiazolyl)carboxamides containing an amino functionality. Synthesis of target furoxanotriazinones 1a–h. The synthesis of furazanotriazinones 7a–h. Control experiment with Na15NO2. Optimization of the diazotization of amide 2aa

Heterocycle-guided synthesis of m-hetarylanilines via three-component benzannulation

• Andrey R. Galeev,
• Maksim V. Dmitriev,
• Alexander S. Novikov and
• Andrey N. Maslivets

Beilstein J. Org. Chem. 2024, 20, 2208–2216, doi:10.3762/bjoc.20.188

• condensation by introducing additional functional groups into the amine moiety (Figure 3). Substituted arylamines bearing alcohol (3ae), phenol (3ad), alkene (3bi), dimethyl acetal (3bj) functionality can be accessed in good yields. Reaction of 1,3-diketone 1a with a non-amidine type heterocyclic amine, 3

Computational toolbox for the analysis of protein–glycan interactions

• Ferran Nieto-Fabregat,
• Maria Pia Lenza,
• Angela Marseglia,
• Cristina Di Carluccio,
• Antonio Molinaro,
• Alba Silipo and
• Roberta Marchetti

Beilstein J. Org. Chem. 2024, 20, 2084–2107, doi:10.3762/bjoc.20.180

• docking software (unfortunately not free) designed to predict the conformations of small molecules in protein binding sites, thus facilitating the discovery of new drugs. Within SeeSAR, its functionality allows ligands to be placed in binding sites using an incremental construction algorithm that splits

Multicomponent syntheses of pyrazoles via (3 + 2)-cyclocondensation and (3 + 2)-cycloaddition key steps

• Ignaz Betcke,
• Alissa C. Götzinger,
• Maryna M. Kornet and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2024, 20, 2024–2077, doi:10.3762/bjoc.20.178

• gives access to polyfunctional ynedione 129 [147]. In contrast to Sonogashira alkynylation, where glyoxyl substrates furnish ynones with concomitant decarbonylation [145], Stephens–Castro alkynylation preserves the dicarbonyl functionality in the product [148]. Embedded within a consecutive four

The Groebke–Blackburn–Bienaymé reaction in its maturity: innovation and improvements since its 21st birthday (2019–2023)

• Cristina Martini,
• Muhammad Idham Darussalam Mardjan and
• Andrea Basso

Beilstein J. Org. Chem. 2024, 20, 1839–1879, doi:10.3762/bjoc.20.162

• the tolerability of a wide range of aldehydes, starting from one of the most used, benzaldehyde, passing through heteroaromatic and aliphatic structures with different substituents. In this context, some examples where the aldehyde functionality is incorporated into sugar derivatives, natural

• economy (water was the only byproduct) and thermal stability as well as remarkable fluorescence properties. Multicomponent reaction can be also employed to prepare crystalline porous materials namely covalent organic frameworks (COFs). The structural diversity and functionality of COFs were assembled from

Hetero-polycyclic aromatic systems: A data-driven investigation of structure–property relationships

• Sabyasachi Chakraborty,
• Eduardo Mayo Yanes and
• Renana Gershoni-Poranne

Beilstein J. Org. Chem. 2024, 20, 1817–1830, doi:10.3762/bjoc.20.160

• have also been incorporated into larger structures such as nano-hoops, in order to tune and expand their functionality [26]. Herein, we perform an in-depth analysis of the data contained within COMPAS-2, aiming to elucidate the effects of electron count, geometry, atomic composition, and aromatic

Syntheses and medicinal chemistry of spiro heterocyclic steroids

• Laura L. Romero-Hernández,
• Ana Isabel Ahuja-Casarín,
• Penélope Merino-Montiel,
• Sara Montiel-Smith,
• José Luis Vega-Báez and
• Jesús Sandoval-Ramírez

Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152

• androgenic activity. Poirier’s group reported two methodologies to prepare spiromorpholin-3-ones from a β-amino alcohol functionality [39]. Spiro compounds were synthesized starting from estrone, in which the phenol group was protected as a methoxymethyl ether. Then, the protected compound was subjected to

• peroxide–hydrochloric acid. A subsequent reaction of the resulting compound with simple ketones in the presence of sulfuric acid produced steroidal 1,2,4,5-tetraoxanes 170 possessing an ester functionality. The unsubstituted ketones gave a single product as expected, while those with substituted precursors

Tetrabutylammonium iodide-catalyzed oxidative α-azidation of β-ketocarbonyl compounds using sodium azide

• Christopher Mairhofer,
• David Naderer and
• Mario Waser

Beilstein J. Org. Chem. 2024, 20, 1510–1517, doi:10.3762/bjoc.20.135

• . Keywords: azidation; nitration; organocatalysis; oxidation; quaternary ammonium iodides; Introduction Organic compounds containing an azide functionality are highly valuable synthesis targets that offer considerable potential for various applications and further manipulations [1][2][3][4][5][6][7][8][9

• in the presence of Bu4NHSO4 (Table 1, entry 9) and the use of Bu4NCl (Table 1, entry 8) was not satisfying either. On the other hand, the beneficial effect of the quaternary ammonium functionality was clearly underscored by employing KI instead of Bu4NI (compare Table 1, entries 10 and 5). While

Synthetic applications of the Cannizzaro reaction

• Bhaskar Chatterjee,
• Dhananjoy Mondal and
• Smritilekha Bera

Beilstein J. Org. Chem. 2024, 20, 1376–1395, doi:10.3762/bjoc.20.120

• synthetic tool for the construction of functionalized molecules. Dating back to the 19th century, this reaction, though initially used for the synthesis of an alcohol and acid functionality from aldehydes, has henceforth proven useful to generate diverse molecular entities using both intermolecular and

• Cannizzaro reaction commencing from 68. The primary hydroxymethyl functionality in 69 was oxidized to the corresponding aldehyde 70, which was subsequently treated with 37% aqueous formaldehyde and NaOH, to result in a mixture of the gem-hydroxymethyl derivative 72 and the carbamate 71 which led to the spiro

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

• ] cycloaddition between maleic anhydride and secondary amine occurs first, followed by the corresponding amidation (Figure 3, path II) [110]. Although IMDAF reactions involving furan systems bearing amide functionality are generally reversible [134], the formation of the addition products in high yields in this

Stability trends in carbocation intermediates stemming from germacrene A and hedycaryol

• Naziha Tarannam,
• Prashant Kumar Gupta,
• Shani Zev and
• Dan Thomas Major

Beilstein J. Org. Chem. 2024, 20, 1189–1197, doi:10.3762/bjoc.20.101

• from the NCI plots. In general, stabilization of some 5-7 bicyclic carbocations (e.g., F-OH and H-OH) are via C+···OH interactions, which are facilitated by the carbocation and hydroxyl functionality being located in the relatively flexible 7-membered ring. This type of interaction is absent in case of

Manganese-catalyzed C–C and C–N bond formation with alcohols via borrowing hydrogen or hydrogen auto-transfer

• Mohd Farhan Ansari,
• Atul Kumar Maurya,
• Abhishek Kumar and
• Saravanakumar Elangovan

Beilstein J. Org. Chem. 2024, 20, 1111–1166, doi:10.3762/bjoc.20.98

• alcohols as an alkylating agent using the protic functionality on a naphthyridine‑N‑oxide manganese complex [68]. The reaction conditions were optimized using acetophenone and benzyl alcohol as model substrates. After optimizing various reaction parameters, 2 mol % of Mn14 and 20 mol % of KOH in toluene

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

• used. There are two obvious choices based on the literature on CDA inhibitors, THU (Ia) and phosphapyrimidine nucleoside IV (Figure 1). However, the hemiaminal functionality in the nucleobase and the fast transformation into pyranose in THU (Ia) along with instability of nucleoside IV in water prevent

Light on the sustainable preparation of aryl-cored dibromides

• Fabrizio Roncaglia,
• Alberto Ughetti,
• Nicola Porcelli,
• Biagio Anderlini,
• Andrea Severini and
• Luca Rigamonti

Beilstein J. Org. Chem. 2024, 20, 1076–1087, doi:10.3762/bjoc.20.95

• molecular wires or extended structures – either linear or cyclic – with enhanced functionality. Consequently, they play a crucial role in the fabrication of polymers [4][5][6][7], cyclophanes [8], photoactive materials [9][10][11], membranes [12], and other architectures. The synthetic potential of aryl

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

• either annulation of an isoxazole fragment to a pyridine cycle or vice versa formation of a pyridine ring based on appropriately substituted isoxazoles. In the first case (Scheme 1A) 3-halo- [11][15][16][17][18][19] or 3-hydroxypyridines [8][20] bearing a suitable functionality in position 2 were used

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

• dicyanopyrazinoquinoxalines (DCPQs) 1a–7a and subsequent mild one-step synthesis of hydrogen-bonding dihydropyrazinoquinoxalinedione (DPQDs) 1b–7b. The structure–property relationships have been established within and between the two families using optical measurements. Moreover, the incorporation of H-bonding functionality

• functionality as well as Buchwald–Hartwig amination involving aryl halides. Thermal studies Thermal stabilities of DCPQs 1a–6a and DPQDs 1b–7b were evaluated using thermogravimetric analysis (TGA; Figure 2 and Table S4 in Supporting Information File 1). The thermal stability of the DCPQs is attributed to their

• DCPQs and DPQDs in this context. Overall, this work contributes to our overarching objective to investigate the influence of hydrogen-bonding functionality on optoelectronic material organization and next-generation organic semiconductor device performance. Experimental General methods Reagents and

Innovative synthesis of drug-like molecules using tetrazole as core building blocks

• Jingyao Li,
• Ajay L. Chandgude,
• Qiang Zheng and
• Alexander Dömling

Beilstein J. Org. Chem. 2024, 20, 950–958, doi:10.3762/bjoc.20.85

• of tetrazole building blocks which provides the handle of alcohol functionality and further oxidation serves as an oxo component in subsequent MCRs (Figure 1d). The synthesis of oxo-tetrazoles was targeted because of the prevalence of the aldehyde substrate in MCRs and their use in medicinal

Monitoring carbohydrate 3D structure quality with the Privateer database

• Jordan S. Dialpuri,
• Haroldas Bagdonas,
• Lucy C. Schofield,
• Phuong Thao Pham,
• Lou Holland and
• Jon Agirre

Beilstein J. Org. Chem. 2024, 20, 931–939, doi:10.3762/bjoc.20.83

• unlikeliness for a human to read and understand the WURCS code. It is much more likely that the WURCS code would be copied and searched for in a glycomics database, hence we provide that functionality in a streamlined way. The final section of the validation report includes all of the validation metrics

(Bio)isosteres of ortho- and meta-substituted benzenes

• H. Erik Diepers and
• Johannes C. L. Walker

Beilstein J. Org. Chem. 2024, 20, 859–890, doi:10.3762/bjoc.20.78

• -workers reported a method for the selective bridge bromination of BCPs, giving access to brominated 1,2-BCP (±)-16 (Scheme 2) [33]. By exploiting the homolytic cleavage of the C–Br bond using in situ-generated silyl radicals, they were then able to harness the installed bromide functionality in

• substituted ortho-benzene. Stephenson and co-workers accessed 1,2-BCHeps 79a–c by insertion of alkenes into BCPs 78, and proposed the 1,2-BCHeps as isosteres of ortho-benzenes (Scheme 7A) [46]. The reaction proceeded via homolytic cleavage of a C–C bond adjacent to the imine functionality and stepwise alkene

Activity assays of NnlA homologs suggest the natural product N-nitroglycine is degraded by diverse bacteria

• Kara A. Strickland,
• Brenda Martinez Rodriguez,
• Ashley A. Holland,
• Shelby Wagner,
• Michelle Luna-Alva,
• David E. Graham and
• Jonathan D. Caranto

Beilstein J. Org. Chem. 2024, 20, 830–840, doi:10.3762/bjoc.20.75

• , reductively decomposes the nitramine functionality of RDX to form •NO2 [38], a toxic reactive nitrogen species. Additionally, NNG is a structural analog of another natural product 3-nitropropionate (3NP) found in plants and fungi [39]. This highly toxic compound inhibited succinate dehydrogenase and other

• in diverse bacteria and environments. These results suggest the natural product NNG may also be found in diverse environments. The reactivity of the nitramine functionality begs for further studies confirming the natural abundance and physiological functions of NNG and other nitramine natural

Synthesis of new representatives of A₃B-type carboranylporphyrins based on meso-tetra(pentafluorophenyl)porphyrin transformations

• Victoria M. Alpatova,
• Evgeny G. Rys,
• Elena G. Kononova and
• Valentina A. Ol'shevskaya

Beilstein J. Org. Chem. 2024, 20, 767–776, doi:10.3762/bjoc.20.70

• the p-fluorine atom in the pentafluorophenyl substituent with an azide functionality which upon reduction with SnCl2 resulted in the formation of the corresponding porphyrin with an amino group. Pentafluorophenyl-substituted A3B-porphyrins were studied and transformed to thiol and amino-substituted

• functionality was supported by the design of conjugates containing maleimide and biotin substituents. The structures of prepared carboranylporphyrins were determined by UV–vis, IR, 1H 19F, 11B NMR spectroscopic data and MALDI mass spectrometry. Synthesis of porphyrins 2 and 3. Synthesis of carborane

Methodology for awakening the potential secondary metabolic capacity in actinomycetes

• Shun Saito and
• Midori A. Arai

Beilstein J. Org. Chem. 2024, 20, 753–766, doi:10.3762/bjoc.20.69

• , respectively. Analyses of the functionality of such metabolites may also lead to the elucidation of new life phenomena. However, in recent years, it has not only become increasingly difficult to obtain novel secondary metabolites from natural products, but applied research using natural products, such as drug

Production of non-natural 5-methylorsellinate-derived meroterpenoids in Aspergillus oryzae

• Jia Tang,
• Yixiang Zhang and
• Yudai Matsuda

Beilstein J. Org. Chem. 2024, 20, 638–644, doi:10.3762/bjoc.20.56

• designated as 5′-demethylinsuetusin A1. Unlike compounds 3–7, the molecular formula of 8 was determined to be C25H38O5, which corresponds to the hydrogenated form of 7. NMR analysis revealed that the double bond at C-2′/C-3′ of 7 was reduced to a single bond in 8 and that 8 contained the enol functionality

A laterally-fused N-heterocyclic carbene framework from polysubstituted aminoimidazo[5,1-b]oxazol-6-ium salts

• Andrew D. Gillie,
• Matthew G. Wakeling,
• Bethan L. Greene,
• Louise Male and
• Paul W. Davies

Beilstein J. Org. Chem. 2024, 20, 621–627, doi:10.3762/bjoc.20.54

• sphere, accessing more diverse fused imidazolium frameworks and different peripheral functionality offers significant scope to influence catalytic properties. Few studies into L-shaped imidazolylidines have explored core motifs beyond ImPy, with NHCs derived from two π-rich rings fused together

Switchable molecular tweezers: design and applications

• Pablo Msellem,
• Maksym Dekthiarenko,
• Nihal Hadj Seyd and
• Guillaume Vives

Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45

• reactions. Electrochemical stimuli, while generating no waste when employing electrodes, may face limitations due to the electroactive window of the solvent and require the incorporation of redox-active switching units, which can impose constraints on design and functionality. It is worth noting that the