The effect of neighbouring group participation and possible long range remote group participation in O-glycosylation

• Rituparna Das and
• Balaram Mukhopadhyay

Beilstein J. Org. Chem. 2025, 21, 369–406, doi:10.3762/bjoc.21.27

• glycosylation. Conventional glycosylation involves the ‘nucleophilic substitution’ of the leaving group at the sp3 anomeric centre of the donor moiety with a suitable carbohydrate or non-carbohydrate-based aglycon with the help of an electrophilic promoter to form the equatorial glycoside 7 or the axial

• temperature or the activation entropy, hydrogen bonding, solvent [24], nature of the leaving groups and the promoter used [25]. The mechanism of glycosylation reactions has long been categorised mostly as dissociative SN1 reactions proceeding through stabilised oxocarbenium ions with the role of counterions

• inversion in carbohydrates was illustrated extensively by Frush and Isbell [75] with silver carbonate as the promoter, drawing analogy with an SN2-type substitution mechanism with the formation of the acetoxonium ion intermediate [76]. An acyl protecting group in the vicinal C-2 position is widely accepted

Molecular diversity of the reactions of MBH carbonates of isatins and various nucleophiles

• Zi-Ying Xiao,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2025, 21, 286–295, doi:10.3762/bjoc.21.21

• spectroscopy techniques. In order to show the universality of the substitution reaction, MBH maleimides of isatins 4 were also employed in the reaction. In the absence of any base as promoter, the reaction of MBH maleimides of isatins with various aromatic amines in toluene at 65 °C gave the expected

• promoter is needed in the reaction, which is assumed to be due to the much higher reactivity of MBH maleimides of isatins compared to the above-mentioned MBH nitriles and formats of isatins. The single crystal structures of the compounds 5a and 5j were successfully determined (Figure 1 and Figure 2). From

Visible-light-promoted radical cyclisation of unactivated alkenes in benzimidazoles: synthesis of difluoromethyl- and aryldifluoromethyl-substituted polycyclic imidazoles

• Yujun Pang,
• Jinglan Yan,
• Nawaf Al-Maharik,
• Qian Zhang,
• Zeguo Fang and
• Dong Li

Beilstein J. Org. Chem. 2025, 21, 234–241, doi:10.3762/bjoc.21.15

• reaction (Table 1). Employing PIDA as the promoter, THF as the solvent, and 72 W white LED as the light source, the desired product 3a formed in 85% isolated yield at room temperature (Table 1, entry 1). We found that the hypervalent iodine reagent was of significant importance for the present

• transformation (Table 1, entries 2 and 3), and PIDA was the most efficient promoter. Changing THF to other solvents, such as DCM, EtOH, DMF, CH3CN, EtOAc, or DMSO, resulted in a lower yield (Table 1, entries 4–9). Furthermore, variations in the amounts of PIDA or CF2HCOOH led to diminished yields (Table 1

Hypervalent iodine-mediated intramolecular alkene halocyclisation

• Charu Bansal,
• Oliver Ruggles,
• Albert C. Rowett and
• Alastair J. J. Lennox

Beilstein J. Org. Chem. 2024, 20, 3113–3133, doi:10.3762/bjoc.20.258

• nucleophiles In 2000, Hara and co-workers reported the fluorocyclisation of unsaturated alcohols and carboxylic acids promoted by HVI reagents (Scheme 11) [36]. Using 4-tolyl difluoroiodane 10 as the reaction promoter, and pyridine·6HF as a source of fluoride, a range of unsaturated alcohols 23 to fluorinated

• as the bromine source and Bu4NBr as a reaction promoter, racemic brominated pyrrolidines 54 were synthesised from a range of homoallylic sulfonamides 53 in excellent yields under mild conditions at room temperature. A mechanism was suggested by the authors (Scheme 29), whereby ligand exchange on PhI

• unsaturated dicarbonyls 74 (Scheme 39) [57]. Using PhI(OAc)2 as an oxidant and TMSBr as a source of bromine and reaction promoter, a range of bromomethyldihydrofurans 75 were cyclised in good yields. Both 5- and 6-membered rings were formed, with homologation of the unsaturated chain. The authors initially

Advances in the use of metal-free tetrapyrrolic macrocycles as catalysts

• Mandeep K. Chahal

Beilstein J. Org. Chem. 2024, 20, 3085–3112, doi:10.3762/bjoc.20.257

• acetonitrile, calix[4]pyrrole enhanced its solubility, contributing to its indirect activation. Various control experiments, such as using CuI with and without calix[4]pyrrole and using dipyrromethane as another potential co-catalyst, have confirmed the role of calix[4]pyrrole as a promoter. Recently

Discovery of antimicrobial peptides clostrisin and cellulosin from Clostridium: insights into their structures, co-localized biosynthetic gene clusters, and antibiotic activity

• Moisés Alejandro Alejo Hernandez,
• Katia Pamela Villavicencio Sánchez,
• Rosendo Sánchez Morales,
• Karla Georgina Hernández-Magro Gil,
• David Silverio Moreno-Gutiérrez,
• Eddie Guillermo Sanchez-Rueda,
• Yanet Teresa-Cruz,
• Brian Choi,
• Armando Hernández Garcia,
• Alba Romero-Rodríguez,
• Oscar Juárez,
• Siseth Martínez-Caballero,
• Mario Figueroa and
• Corina-Diana Ceapă

Beilstein J. Org. Chem. 2024, 20, 1800–1816, doi:10.3762/bjoc.20.159

• -translational modification enzymes The selected supercluster is predicted to be formed by two adjacent, biosynthetically complete transcriptional units, each with specific promoter and terminator sites (Figure 2) containing two LanM enzymes (CloM1 and CloM2), the precursor peptides CloA1 and CloA2, as well as

Ligand effects, solvent cooperation, and large kinetic solvent deuterium isotope effects in gold(I)-catalyzed intramolecular alkene hydroamination

• Ruichen Lan,
• Brock Yager,
• Yoonsun Jee,
• Cynthia S. Day and
• Amanda C. Jones

Beilstein J. Org. Chem. 2024, 20, 479–496, doi:10.3762/bjoc.20.43

• , and benzamide 1c (Table 4). Under standard conditions (2.5 mol % [JPhosAu(NCCH3)]SbF6, 0.05 M alkene in DCM) benzamide and carbamate hydroamination were too slow to measure, so the reactions were done with 55 μL MeOH promoter but still only an estimated rate constant was obtained for 1c (14

• achieved – benzamide (1c) cyclization with Jackiephos and 55 μL MeOH promoter matches the rate of cyclization of carbamate (1b) with JPhosAu(NCCH3)SbF6 with only 5 μL MeOH promoter (see Supporting Information File 1, Figure S18). Increasing to 100 μL MeOH did not increase the benzamide cyclization rate any

Green and sustainable approaches for the Friedel–Crafts reaction between aldehydes and indoles

• Periklis X. Kolagkis,
• Eirini M. Galathri and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2024, 20, 379–426, doi:10.3762/bjoc.20.36

Elucidating the glycan-binding specificity and structure of Cucumis melo agglutinin, a new R-type lectin

• Jon Lundstrøm,
• Emilie Gillon,
• Valérie Chazalet,
• Nicole Kerekes,
• Antonio Di Maio,
• Ten Feizi,
• Yan Liu,
• Annabelle Varrot and
• Daniel Bojar

Beilstein J. Org. Chem. 2024, 20, 306–320, doi:10.3762/bjoc.20.31

• cytomegalovirus (CMV) promoter. Then, the Mammalian Protein Expression core facility at the University of Gothenburg transfected this plasmid into FreeStyle™ CHO-S cells (Cat nr R80007, ThermoFisher Scientific). Cells were cultured in Freestyle™ CHO medium at 37 °C in 5% CO2 in Optimum GrowthTM flasks (Thomson

Comparison of glycosyl donors: a supramer approach

• Anna V. Orlova,
• Nelly N. Malysheva,
• Maria V. Panova,
• Nikita M. Podvalnyy,
• Michael G. Medvedev and
• Leonid O. Kononov

Beilstein J. Org. Chem. 2024, 20, 181–192, doi:10.3762/bjoc.20.18

• a reaction solvent might not be as relevant when the reaction solution contains also glycosyl acceptor, promoter, suspended molecular sieves, etc., in addition to the glycosyl donor, and the presence of these components may also affect [31][32][33] solution structure and hence the glycosylation

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

• regulator (cmaR), under the control of tipA promoter (Figure 2A). When we cultured S. albus-cma and analyzed its metabolites by liquid chromatography–mass spectrometry (LC–MS), formation of avenalumic acid was not observed. Instead, production of p-coumaric acid (5) was detected (Figure 2B and Figure S3A,D

• expression of BGCs combined with promoter swapping is a powerful tool for the discovery of new natural products from rare actinomycetes. Conclusion In summary, we identified a cma gene cluster for p-coumaric acid biosynthesis in the K. albida genome. We demonstrated the following two biosynthetic reactions

• gene sets on heterologous expression plasmids to construct S. albus-cma. The tipA promoter was used for gene expression. B) Metabolite analysis of S. albus-cma. UV chromatograms at 310 nm are shown. The production yield of 6 was decreased in S. albus-cma ∆cmaG. Several metabolites produced by S. albus

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

• , reflux, 2 h) when anhydrous hydrazine (4.2 equiv) was used as a promoter. A plausible pathway for the transformation of imidate 4 into macrocycle 5 is shown in Scheme 3. This pathway includes fast substitution of the ethoxy group by hydrazine to give the intermediate amidrazone 7 followed by its rapid

• varying promoter, its amount, solvent, substrate concentration, and reaction time (Table 1). First, we studied the dimerization of 8 promoted by hydrazine hydrate in EtOH under reflux (Table 1, entries 1–3). We found that the starting material was completely consumed in the presence of 3 equivalents of

N-Sulfenylsuccinimide/phthalimide: an alternative sulfenylating reagent in organic transformations

• Fatemeh Doraghi,
• Seyedeh Pegah Aledavoud,
• Mehdi Ghanbarlou,
• Bagher Larijani and
• Mohammad Mahdavi

Beilstein J. Org. Chem. 2023, 19, 1471–1502, doi:10.3762/bjoc.19.106

• of N-(arylsulfanyl)succinimide 1 and N-(arylseleno)succinimide 1’’ in an oxychalcogenation process was reported in 2018 (Scheme 54) [86]. In this method, they succeeded in applying methanesulfonic acid (MsOH) as a promoter for oxythiolation and oxyselenation of o-vinylanilides 127 through the

One-pot synthesis of 2-arylated and 2-alkylated benzoxazoles and benzimidazoles based on triphenylbismuth dichloride-promoted desulfurization of thioamides

• Arisu Koyanagi,
• Yuki Murata,
• Shiori Hayakawa,
• Mio Matsumura and
• Shuji Yasuike

Beilstein J. Org. Chem. 2022, 18, 1479–1487, doi:10.3762/bjoc.18.155

• as a promoter afforded various 2-aryl- and 2-alkylbenzoxazoles in moderate to excellent yields under mild reaction conditions. This method could also be applied to the synthesis of benzimidazoles and benzothiazoles. This study presents the first use of triphenylbismuth dichloride to produce

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

• cyclized only in the presence of acid as a promoter [21], while with trishydrazones 3 the process takes place only at elevated temperatures. Thus, a synergistic effect of the oxime and hydrazone groups on the intramolecular cyclotrimerization reaction takes place. The structure of 1N,2O-TAAD 8a was secured

From amines to (form)amides: a simple and successful mechanochemical approach

• Federico Casti,
• Rita Mocci and
• Andrea Porcheddu

Beilstein J. Org. Chem. 2022, 18, 1210–1216, doi:10.3762/bjoc.18.126

• desired formamide 2 (71% NMR yield, Table S1 in Supporting Information File 1), denoting the input given by imidazole as a promoter of formamide synthesis. Further variation in the ratio of imidazole/formic acid/amine decreases the reaction yield (Table S1 in Supporting Information File 1). These data

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

• acetonitrile at room temperature gave the unexpected products 4a–k in moderate to good yields in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) as base promoter and the results are summarized in Table 3. It can be seen that the products 4a–k contain two scaffolds of each phenacylmalononitrile and

Efficient production of clerodane and ent-kaurane diterpenes through truncated artificial pathways in Escherichia coli

• Fang-Ru Li,
• Xiaoxu Lin,
• Qian Yang,
• Ning-Hua Tan and
• Liao-Bin Dong

Beilstein J. Org. Chem. 2022, 18, 881–888, doi:10.3762/bjoc.18.89

• producing terpentetriene and ent-kaurene from ISO and DMAA (Figure 3). To decrease the burden on the host cell [38], the six genes (phoN, ipk, idi, ggdps, tdps, and ttes) leading to the production of terpentetriene, each with a strong and inducible T7 promoter, were cloned into pETDuet-1 plasmid to form

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

Total synthesis of the O-antigen repeating unit of Providencia stuartii O49 serotype through linear and one-pot assemblies

• Tanmoy Halder and
• Somnath Yadav

Beilstein J. Org. Chem. 2021, 17, 2915–2921, doi:10.3762/bjoc.17.199

• acceptor 9 in the presence of TMSOTf as promoter (Scheme 5). After 1 h of reaction, TLC monitoring indicated the full consumption of the starting materials. Analysis of a small aliquot of the reaction mixture by HRMS confirmed the formation of the desired disaccharide. Then, to the same pot, the second

Iron-catalyzed domino coupling reactions of π-systems

• Austin Pounder and
• William Tam

Beilstein J. Org. Chem. 2021, 17, 2848–2893, doi:10.3762/bjoc.17.196

• another role in the reaction, potentially as a promoter of the catalyst. In 2020, Li and co-workers investigated a carbosilylation cascade for the synthesis of various silylated dihydroisoquinolinones and 1,3-isoquinolinediones 95 (Scheme 18) [96]. The scope of the reaction was broad and could tolerate a

Synthetic strategies toward 1,3-oxathiolane nucleoside analogues

• Umesh P. Aher,
• Dhananjai Srivastava,
• Girij P. Singh and
• Jayashree B. S

Beilstein J. Org. Chem. 2021, 17, 2680–2715, doi:10.3762/bjoc.17.182

• reactions, along with recent new promoter-dependent advances. It is generally agreed that the stereochemical outcome of glycosylation can be affected by multiple factors [66][67][68][69], which include i) structure and conformation of the glycosyl substrates, ii) glycosylation reagents or promoters, iii

• directly with the presilylated cytosine without any promoter or additive and gave nucleoside 93 in a selective manner (β/α 10:1). The ester group of nucleoside derivative 93 was further reduced with sodium borohydride in ethanol, which gave lamivudine (1). An efficient and enantioselective synthesis of

A systems-based framework to computationally describe putative transcription factors and signaling pathways regulating glycan biosynthesis

• Theodore Groth,
• Rudiyanto Gunawan and
• Sriram Neelamegham

Beilstein J. Org. Chem. 2021, 17, 1712–1724, doi:10.3762/bjoc.17.119

• proximal to the promoter regions of genes, facilitating the binding of RNA polymerases. They may homotropically or heterotropically associate with additional TFs in order to directly or indirectly control messenger RNA (mRNA) expression. Among the TFs, some “pioneer factors” can pervasively regulate gene

• acetylation, methylation, and phosphorylation, which alter TF access; and iii) methylation of CpG islands in promoter regions that inhibit gene expression [4][5]. There are currently several isolated studies of TF–glycogene interactions, but a systematic “systems-level analysis” is absent. Many of these

• previous studies are based on discrete glycogene promoter region analysis and reporter assays. These studies have established some notable TF–glycogene relationships, though they are limited to distinct cell types. Examples include the regulation of MGAT5 by ETS2 in NIH3T3 fibroblasts [6], control of the

N-tert-Butanesulfinyl imines in the asymmetric synthesis of nitrogen-containing heterocycles

• Joseane A. Mendes,
• Paulo R. R. Costa,
• Miguel Yus,
• Francisco Foubelo and
• Camilla D. Buarque

Beilstein J. Org. Chem. 2021, 17, 1096–1140, doi:10.3762/bjoc.17.86

• under solvent-free conditions was carried out, using sodium carbonate as base promoter. The resulting dimethyl 2-(1-aminoalkyl)malonates 50 were obtained in moderate to good yields as single diastereoisomers in all cases except for aromatic aldimines. Compounds 50 could be easily transformed

Prins cyclization-mediated stereoselective synthesis of tetrahydropyrans and dihydropyrans: an inspection of twenty years

• Asha Budakoti,
• Pradip Kumar Mondal,
• Prachi Verma and
• Jagadish Khamrai

Beilstein J. Org. Chem. 2021, 17, 932–963, doi:10.3762/bjoc.17.77

• allylic geminal bissilyl alcohol 221 for the construction of THP ring A of (−)-exiguolide via Prins cyclization with an aldehyde in the presence of Lewis acid as a promoter [95]. High yield and excellent diastereoselectivity were obtained under standard silyl-Prins cyclization conditions using TMSOTf as