A metal-free approach for the synthesis of amides/esters with pyridinium salts of phenacyl bromides via oxidative C–C bond cleavage

• Kesari Lakshmi Manasa,
• Yellaiah Tangella,
• Namballa Hari Krishna and
• Mallika Alvala

Beilstein J. Org. Chem. 2019, 15, 1864–1871, doi:10.3762/bjoc.15.182

• [6][7], anhydrides [8], esters [9], and acyl azides [10] with amines by employing coupling reagents [11]. Alternative protocols include the Staudinger–Vilarrasa reaction [12], Schmidt reaction [13][14], Beckmann rearrangement [15], aminocarbonylation of aryl halides [16], Staudinger ligation [17

Cyclopropene derivatives of aminosugars for metabolic glycoengineering

• Jessica Hassenrück and
• Valentin Wittmann

Beilstein J. Org. Chem. 2019, 15, 584–601, doi:10.3762/bjoc.15.54

• , azides and alkynes can be visualized by the Staudinger ligation [8] or the azide–alkyne cycloaddition, that can be performed either copper-catalyzed [9][10] or strain-promoted [11][12]. Another type of reporter group that has been proven to be a valuable tool are electron-rich or strained alkenes, that

Artificial bioconjugates with naturally occurring linkages: the use of phosphodiester

• Takao Shoji,
• Hiroki Fukutomi,
• Yohei Okada and
• Kazuhiro Chiba

Beilstein J. Org. Chem. 2018, 14, 1946–1955, doi:10.3762/bjoc.14.169

• synthesis, otherwise subsequent steps are complicated. Synthetic chemists, armed with various elegant artificial orthogonal bond formations, including alkyne–azide cycloaddition [27][28][29][30][31][32][33][34], thiol–ene ligation [35][36][37][38], Staudinger ligation [39][40], inverse-electron-demand Diels

An eco-compatible strategy for the diversity-oriented synthesis of macrocycles exploiting carbohydrate-derived building blocks

• Sushil K. Maurya and
• Rohit Rana

Beilstein J. Org. Chem. 2017, 13, 1106–1118, doi:10.3762/bjoc.13.110

• the synthesis. The cyclization of the linear precursor is usually achieved by utilizing various ring-closing reactions such as Diels–Alder reactions, [15] aldol reactions, [16] copper-catalyzed azide–alkyne cycloaddition, [17][18] macrolactonization, macrolactamizations, Staudinger ligation or

Correction: Synthesis, dynamic NMR characterization and XRD studies of novel N,N’-substituted piperazines for bioorthogonal labeling

• Constantin Mamat,
• Marc Pretze,
• Matthew Gott and
• Martin Köckerling

Beilstein J. Org. Chem. 2017, 13, 301–302, doi:10.3762/bjoc.13.32

• : building blocks; coalescence; dynamic NMR; labeling; Staudinger ligation; In the original article an incorrect caption for Figure 1 was given. The assignment of the solvents to the capital letters was not correct. The correct caption of Figure 1 is: 1H NMR spectra of compound 3a measured in five different

Synthesis, dynamic NMR characterization and XRD studies of novel N,N’-substituted piperazines for bioorthogonal labeling

• Constantin Mamat,
• Marc Pretze,
• Matthew Gott and
• Martin Köckerling

Beilstein J. Org. Chem. 2016, 12, 2478–2489, doi:10.3762/bjoc.12.242

• applicability of these compounds as possible 18F-building blocks, two biomolecules were modified and chosen for conjugation either using the Huisgen-click reaction or the traceless Staudinger ligation. Keywords: building blocks; coalescence; dynamic NMR; labeling; Staudinger ligation; Introduction The

• to demonstrate the Cu-catalyzed azide–alkyne click reaction (Huisgen 1,3-dipolar cycloaddition) and the traceless Staudinger ligation, a proof of concept study was performed for the site-selective labeling of a pharmacologically active peptide and a small organic compound. These compounds provide the

• tosylate to yield compounds 5a,b in high yields of 87% and 81%, respectively. These derivatives can be utilized for both variants of the Staudinger ligation in addition to the classical and strain-promoted variants of the Huisgen-click reaction. For future radiolabeling procedures, nitro derivatives 4a and

Articulated rods – a novel class of molecular rods based on oligospiroketals (OSK)

• Pablo Wessig,
• Roswitha Merkel and
• Peter Müller

Beilstein J. Org. Chem. 2015, 11, 74–84, doi:10.3762/bjoc.11.11

• give 36 (Scheme 8). Besides the widely used CuAAC ligation the Staudinger ligation [22] is also an important tool for coupling molecules. To verify that the diazide 34 is also suitable for this reaction we first prepared the cinnamoyl substituted phosphane 38 from (2-hydroxyphenyl)diphenylphosphane (37

• ). By heating 34 and 38 in DMF for 3 h the AR 39 was obtained as result of a traceless Staudinger ligation, albeit with low yield (Scheme 9). As already mentioned, we were interested in articulated rods whose folded-stretched equilibrium could be influenced by external stimuli. In order to realize this

Expanding the scope of cyclopropene reporters for the detection of metabolically engineered glycoproteins by Diels–Alder reactions

• Anne-Katrin Späte,
• Verena F. Schart,
• Julia Häfner,
• Andrea Niederwieser,
• Thomas U. Mayer and
• Valentin Wittmann

Beilstein J. Org. Chem. 2014, 10, 2235–2242, doi:10.3762/bjoc.10.232

• bioorthogonal labeling reactions that allow visualization [5][6]. Whereas in the first report on glycan labeling by this approach the ketone–hydrazide ligation was employed [7], later investigations mainly relied on the Staudinger ligation [8] and azide–alkyne [3 + 2] cycloaddition (copper-catalyzed [9][10] or

Automated solid-phase peptide synthesis to obtain therapeutic peptides

• Veronika Mäde,
• Sylvia Els-Heindl and
• Annette G. Beck-Sickinger

Beilstein J. Org. Chem. 2014, 10, 1197–1212, doi:10.3762/bjoc.10.118

• obtain the desired polypeptide. The condensation can occur via chemoselective ligation techniques such as native chemical ligation (NCL), expressed protein ligation (EPL), Staudinger ligation or click reaction [8][79]. Recently, peptide drugs as the pharmaceuticals Enfuvirtide, Eptifibitide and

Staudinger ligation towards cyclodextrin dimers in aqueous/organic media. Synthesis, conformations and guest-encapsulation ability

• Malamatenia D. Manouilidou,
• Yannis G. Lazarou,
• Irene M. Mavridis and
• Konstantina Yannakopoulou

Beilstein J. Org. Chem. 2014, 10, 774–783, doi:10.3762/bjoc.10.73

• , 15310 Greece. Tel. +30210 6503796, Fax: +30 210 6511766 10.3762/bjoc.10.73 Abstract β-Cyclodextrin (β-CD) dimers have been prepared using the bioorthogonal Staudinger ligation for the first time. In addition to a known linker, methyl 2-(diphenylphosphanyl)terephthalate, a doubly active linker was

• conformations which bring the phenyl groups either inside the β-CD cavity (inclusion) or over its narrow side (vicinal). Thus, Staudinger ligation could be the method of choice for linking CDs exhibiting (i) ease of preparation in aqueous media, in short steps, under mild conditions and in good yields, (ii

• ) satisfactory aqueous solubility and independent binding capacity of the cavities. Keywords: calculations; conformations; cyclodextrin; dimer; inclusion; PM3; Staudinger ligation; Introduction The Staudinger reaction [1] is a classical method for the preparation of amines from phosphines and azides [2][3

Peptoids and polyamines going sweet: Modular synthesis of glycosylated peptoids and polyamines using click chemistry

• Daniel Fürniss,
• Timo Mack,
• Frank Hahn,
• Sidonie B. L. Vollrath,
• Katarzyna Koroniak,
• Ute Schepers and
• Stefan Bräse

Beilstein J. Org. Chem. 2013, 9, 56–63, doi:10.3762/bjoc.9.7

• conjugation methods such as the Staudinger ligation [1] or the copper-catalyzed alkyne azide cycloaddition (CuAAC) [2][3], a large number of versatile and functional bioconjugates are accessible for various applications in chemical biology [4]. To date, many therapeutically active molecules are synthetic

S-Fluorenylmethyl protection of the cysteine side chain upon N^α-Fmoc deprotection

• Johannes W. Wehner and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2012, 8, 2149–2155, doi:10.3762/bjoc.8.242

• mannopyranside 4 can be prepared by Staudinger ligation of O-acetyl-protected 2-azidoethyl α-D-mannopyranoside [11] and the cysteine derivative Fmoc-Cys(Trt)-OH as described earlier [1]. Then, a sequence of Fmoc-deprotection, leading to 5 and acidic removal of the trityl group by using TFA and triethylsilane

The Amadori rearrangement as glycoconjugation method: Synthesis of non-natural C-glycosyl type glycoconjugates

• Katharina Gallas,
• Gerit Pototschnig,
• Florian Adanitsch,
• Arnold E. Stütz and
• Tanja M. Wrodnigg

Beilstein J. Org. Chem. 2012, 8, 1619–1629, doi:10.3762/bjoc.8.185

• chemistry (Huisgen cycloaddition) [4][5], glycosylation protocols [6][7], and Staudinger ligation [8], just to mention the most prominent examples. However, many applications in this respect require a ligation method that is functional in aqueous medium, and, for economic purposes in general, protecting

Synthesis of coumarin or ferrocene labeled nucleosides via Staudinger ligation

• Ivana Kosiova,
• Andrea Janicova and
• Pavol Kois

Beilstein J. Org. Chem. 2006, 2, No. 23, doi:10.1186/1860-5397-2-23

• gives iminophosphoranes which can react with almost any kind of electrophilic reagent, e.g. aldehydes/ketones to form imines or esters to form amides. This so-called Staudinger ligation has been employed in a wide range of applications as a general tool for bioconjugation including specific labeling of

• nucleic acids. Results A new approach for the preparation of labeled nucleosides via intermolecular Staudinger ligation is described. Reaction of azidonucleosides with triphenylphosphine lead to iminophosphorane intermediates, which react subsequently with derivatives of coumarin or ferrocene to form

• coumarin or ferrocene labeled nucleosides. Fluorescent properties of coumarin labeled nucleosides are determined. Conclusion New coumarin and ferrocene labeled nucleosides were prepared via intermolecular Staudinger ligation. This reaction joins the fluorescent coumarin and biospecific nucleoside to the