Interactions between shape-persistent macromolecules as probed by AFM

• Johanna Blass,
• Jessica Brunke,
• Franziska Emmerich,
• Cédric Przybylski,
• Vasil M. Garamus,
• Artem Feoktystov,
• Roland Bennewitz,
• Gerhard Wenz and
• Marcel Albrecht

Beilstein J. Org. Chem. 2017, 13, 938–951, doi:10.3762/bjoc.13.95

• -monoamino-6-deoxy-β-CD [52] using N,N’-dicyclohexyl-carbodiimide (DCC) and 1-hydroxybenzotriazole (HOBt) applying a procedure known for terephthalic acid [53]. The resulting product, monomer 7, was easily isolated due to its low solubility in water which was attributed to self-inclusion between hydrophobic

Synthesis and evaluation of anti-oxidant and cytotoxic activities of novel 10-undecenoic acid methyl ester based lipoconjugates of phenolic acids

• Naganna Narra,
• Shiva Shanker Kaki,
• Rachapudi Badari Narayana Prasad,
• Sunil Misra,
• Koude Dhevendar,
• Venkateshwarlu Kontham and
• Padmaja V. Korlipara

Beilstein J. Org. Chem. 2017, 13, 26–32, doi:10.3762/bjoc.13.4

• showed interesting activity. Experimental Materials 10-Undecenoic acid, 1,1’-azobis(cyclohexanecarbonitrile) (ABCN), hydroxybenzotriazole (HOBt) and 1-ethyl-3-(3’-dimethylaminopropyl)carbodiimide hydrochloride (EDC·HCl), cysteamine hydrochloride, cinnamic acid, sinapic acid, ferulic acid, p-coumaric acid

Identification, synthesis and mass spectrometry of a macrolide from the African reed frog Hyperolius cinnamomeoventris

• Markus Menke,
• Pardha Saradhi Peram,
• Iris Starnberger,
• Walter Hödl,
• Gregory F.M. Jongsma,
• David C. Blackburn,
• Mark-Oliver Rödel,
• Miguel Vences and
• Stefan Schulz

Beilstein J. Org. Chem. 2016, 12, 2731–2738, doi:10.3762/bjoc.12.269

• , followed by esterification with 9-decenoic acid (8) using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and 4-(dimethylamino)pyridine (DMAP) [24][25]. The following RCM was performed using Grubbs–Hoveyda II catalyst (11) and hexafluorobenzene as an additive [26]. During the reaction isomerization

Catalytic Wittig and aza-Wittig reactions

• Zhiqi Lao and
• Patrick H. Toy

Beilstein J. Org. Chem. 2016, 12, 2577–2587, doi:10.3762/bjoc.12.253

• example of a catalytic aza-Wittig reaction as part of their research on phosphine oxide-catalyzed carbodiimide synthesis (Scheme 13) [30]. In their reaction they used phosphine oxide 40 as the catalyst in the reaction between diisocyanate 41 and benzaldehyde (42, 2 equivalents) to form diimine 43 and

Synthesis and NMR studies of malonyl-linked glycoconjugates of N-(2-aminoethyl)glycine. Building blocks for the construction of combinatorial glycopeptide libraries

• Markus Nörrlinger,
• Sven Hafner and
• Thomas Ziegler

Beilstein J. Org. Chem. 2016, 12, 1939–1948, doi:10.3762/bjoc.12.183

• )carbodiimide (EDCI) (Scheme 1, Table 1). In general, HBTU gave higher yields of malonamides 1a–d than EDCI. Previously, we used EDCI for coupling acids 6a–d to aniline derivatives because HBTU resulted in byproducts which were difficult to be removed [14]. Such byproducts were not observed here though. Next

Rearrangements of organic peroxides and related processes

• Ivan A. Yaremenko,
• Vera A. Vil’,
• Dmitry V. Demchuk and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162

• generated peracids from carbodiimide, hydrogen peroxide, and carboxylic acids as catalysts ketones 37 are rearranged to lactones 38 (Scheme 11) [229]. 3,4-Dimethoxybenzoic acid (40) was prepared with 78% yield by a Baeyer–Villiger reaction of substrate 39 with 30% H2O2, HCOOH and 1,2-dichloroethane at 50 °C

Application of Cu(I)-catalyzed azide–alkyne cycloaddition for the design and synthesis of sequence specific probes targeting double-stranded DNA

• Svetlana V. Vasilyeva,
• Vyacheslav V. Filichev and
• Alexandre S. Boutorine

Beilstein J. Org. Chem. 2016, 12, 1348–1360, doi:10.3762/bjoc.12.128

• the most stable complexes are formed by antiparallel G-rich TINA-TFOs [17][18] (Figure 1). The conjugation of TINA-TFOs to MGBs should allow for recognition of longer sequences in dsDNA than for the parent components thus providing improved affinity and sequence specificity [11]. Using carbodiimide

Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

• Mohammad Haji

Beilstein J. Org. Chem. 2016, 12, 1269–1301, doi:10.3762/bjoc.12.121

• one-pot reaction of carbodiimide 197, isocyanide 199 and dialkyl phosphonates 198 under optimized conditions (10 mol % of Pd(OAc)2, 10 mol % of FeCl3, 10 mol % of DPPF, 3.0 equiv of Cs2CO3, toluene, reflux) led to (4-imino-3,4-dihydroquinazolin-2-yl)phosphonates 203 in 37–78% yields (Scheme 42). This

• process involves an initial nucleophilic addition of phosphite to carbodiimide 197 affording intermediate 200 which undergoes an oxidative addition of Pd(0) to give Pd(II) species 201. Subsequently, the insertion of isocyanide 199 to species 201 affords intermediate 202, which finally generates

New synthetic strategies for xanthene-dye-appended cyclodextrins

• Milo Malanga,
• Andras Darcsi,
• Mihaly Balint,
• Gabor Benkovics,
• Tamas Sohajda and
• Szabolcs Beni

Beilstein J. Org. Chem. 2016, 12, 537–548, doi:10.3762/bjoc.12.53

• agents for the carboxylic acid were HOBt and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC). Fang and co-workers designed a ratiometric sensor for detecting mercury ions in aqueous media, some biological fluids and living cells based on a rhodamine-modified β-CD [16]. The synthetic strategy was a

Enabling technologies and green processes in cyclodextrin chemistry

• Giancarlo Cravotto,
• Marina Caporaso,
• Laszlo Jicsinszky and
• Katia Martina

Beilstein J. Org. Chem. 2016, 12, 278–294, doi:10.3762/bjoc.12.30

• studied for binding Gd(III) chelates that bear hydrophobic substituents and negative charges [35]. These bio-polymers were easily prepared in two reaction steps by reacting CDs with maleic anhydride followed by activation with carbodiimide to form amide linkages with amino groups of chitosan. The

• esterification of CD was promoted by MW irradiation, while the chitosan coupling used a water-soluble carbodiimide, N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride, under US. A mild sonication at rt using HDI enabled efficient CDs reticulation in the presence of lipases (Scheme 7) whose biocatalytic

Solving the puzzling competition of the thermal C²–C⁶ vs Myers–Saito cyclization of enyne-carbodiimides

• Anup Rana,
• Mehmet Emin Cinar,
• Debabrata Samanta and
• Michael Schmittel

Beilstein J. Org. Chem. 2016, 12, 43–49, doi:10.3762/bjoc.12.6

• –Saito pathway is guided by the inability of the Myers–Saito diradical to kinetically compete in the rate-determining trapping reactions, either inter- or intramolecular, with the concerted C2–C6 cyclization. As demonstrated with enyne-carbodiimide 11, the Myers–Saito channel can be made the preferred

• (Scheme 1) can be switched between C2–C6 and Myers–Saito reaction channels depending on the substitution at the alkyne terminus, as disclosed by Schmittel [18] and Wang [19]. In 1998, Schmittel et al. [18] reported that the thermolysis of enyne-carbodiimide 1a in toluene/1,4-cyclohexadiene yielded the

• Myers–Saito product 3a, whereas the thermolysis of enyne-carbodiimide 1b produced the C2–C6 product 6b. In 1999 Wang et al. [19] stated that the thermal cyclization of enyne-carbodiimides 1c furnished C2–C6 (Schmittel) products 6c in p-xylene under reflux conditions. Based on the experimental findings

Synthesis of tripodal catecholates and their immobilization on zinc oxide nanoparticles

• Franziska Klitsche,
• Julian Ramcke,
• Julia Migenda,
• Andreas Hensel,
• Tobias Vossmeyer,
• Horst Weller,
• Silvia Gross and
• Wolfgang Maison

Beilstein J. Org. Chem. 2015, 11, 678–686, doi:10.3762/bjoc.11.77

• times. Synthesis of tripodal catecholates for surface immobilization. PEG-triscatecholate 3 was synthesized from 1 according to literature [31]. Abbreviations: PEG = poly(ethylene glycol) (5 kDa); EDC = 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide; DMAP = 4-(dimethylamino)pyridine; HOBt

3-Glucosylated 5-amino-1,2,4-oxadiazoles: synthesis and evaluation as glycogen phosphorylase inhibitors

• Marion Donnier-Maréchal,
• David Goyard,
• Vincent Folliard,
• Tibor Docsa,
• Pal Gergely,
• Jean-Pierre Praly and
• Sébastien Vidal

Beilstein J. Org. Chem. 2015, 11, 499–503, doi:10.3762/bjoc.11.56

• ’-dialkylcarbodiimides or Vilsmeier salts. The 5-amino group introduced on the oxadiazole scaffold was expected to provide better inhibition of GP through potential additional interactions with the enzyme’s catalytic site; however, no inhibition was observed at 625 µM. Keywords: amidoxime; carbodiimide; glycogen

• and converted into their Vilsmeier salts, which upon condensation with the amidoxime afforded the dialkylated 5-amino-1,2,4-oxadiazoles. Condensation of three commercially available carbodiimides led to two mono-alkylated 5-amino products, while the aromatic (i.e., tolyl) carbodiimide did not provide

Sequence-specific RNA cleavage by PNA conjugates of the metal-free artificial ribonuclease tris(2-aminobenzimidazole)

• Friederike Danneberg,
• Alice Ghidini,
• Plamena Dogandzhiyski,
• Elisabeth Kalden,
• Roger Strömberg and
• Michael W. Göbel

Beilstein J. Org. Chem. 2015, 11, 493–498, doi:10.3762/bjoc.11.55

• include metal salts like CuCl2 or HgCl2 and carbodiimides such as 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDCI) or N,N’-diisopropylcarbodiimide (DIC) [17]. Another method developed by Lipton et al. uses Mukaiyama's reagent (2-chloro-1-methylpyridinium iodide) to prepare guanidines in high yields

Chemoselective O-acylation of hydroxyamino acids and amino alcohols under acidic reaction conditions: History, scope and applications

• Tor E. Kristensen

Beilstein J. Org. Chem. 2015, 11, 446–468, doi:10.3762/bjoc.11.51

• Bretschneider and Biemann to the diacetylation of 3,4-dihydroxyphenylalanine (DOPA), opening up for their improved synthesis of poly-DOPA [15]. As part of their influential studies on carbodiimide coupling agents for peptide synthesis, Sheehan, Goodman and Hess reported, in 1956, a chemoselective O-acetylation

A one-pot multistep cyclization yielding thiadiazoloimidazole derivatives

• Debabrata Samanta,
• Anup Rana,
• Jan W. Bats and
• Michael Schmittel

Beilstein J. Org. Chem. 2014, 10, 2989–2996, doi:10.3762/bjoc.10.317

• Main, Germany 10.3762/bjoc.10.317 Abstract A versatile synthetic procedure is described to prepare the benzimidazole-fused 1,2,4-thiadiazoles 2a–c via a methanesulfonyl chloride initiated multistep cyclization involving the intramolecular reaction of an in-situ generated carbodiimide with a thiourea

• unit. The structure of the intricate heterocycle 2a was confirmed by single-crystal X-ray analysis and its mechanism of formation supported by DFT computations. Keywords: carbodiimide; cyclization; dithiourea; DFT; 1,2,4-thiadiazoles; Introduction Heterocyclic rings are key components in many

• ://www.ccdc.cam.ac.uk/data_request/cif. The reagent used herein is a convenient one to prepare carbodiimides from thiourea derivatives [11][12][13]. Therefore, the reaction mechanism is envisioned to proceed via the initial formation of one carbodiimide unit in 3 (Scheme 2). The (N=C=N) unit experiences an

(2R,1'S,2'R)- and (2S,1'S,2'R)-3-[2-Mono(di,tri)fluoromethylcyclopropyl]alanines and their incorporation into hormaomycin analogues

• Armin de Meijere,
• Sergei I. Kozhushkov,
• Dmitrii S. Yufit,
• Christian Grosse,
• Marcel Kaiser and
• Vitaly A. Raev

Beilstein J. Org. Chem. 2014, 10, 2844–2857, doi:10.3762/bjoc.10.302

• secondary (4-Pe)Pro moiety and the hydroxy group of allo-Thr. Among several methods described in the literature for the creation of such bonds, the dialkylaminopyridine-promoted carbodiimide-mediated esterification was successfully employed here [62]. As far as the biological activities against L. donovani

Detonation nanodiamonds biofunctionalization and immobilization to titanium alloy surfaces as first steps towards medical application

• Juliana P. L. Gonçalves,
• Afnan Q. Shaikh,
• Manuela Reitzig,
• Daria A. Kovalenko,
• Jan Michael,
• René Beutner,
• Gianaurelio Cuniberti,
• Dieter Scharnweber and
• Jörg Opitz

Beilstein J. Org. Chem. 2014, 10, 2765–2773, doi:10.3762/bjoc.10.293

• of MES containg 6 mg of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC). The mixture was stirred for 20 min at room temperature. Afterwards, 25 mL of O-phosphorylethanolamine (8% aqueous) solution was added to the activated particles and the suspension was stirred for 2.5 h at room temperature

• -phosphorylethanolamine (O-PEA), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), 2-(N-morpholinoethanesulfonic acid), room temperature, 2.5 h; (iii) Sodium borohydride, ethanol, 60 °C, 24 h, (iv) (3-aminopropyltrimethoxysilane (APTMS), acidic environment, room temperature, 48 h, (v) O-PEA, EDC, 4-(dimethylamino

Synthesis and biological evaluation of novel N-α-haloacylated homoserine lactones as quorum sensing modulators

• Michail Syrpas,
• Ewout Ruysbergh,
• Christian V. Stevens,
• Norbert De Kimpe and
• Sven Mangelinckx

Beilstein J. Org. Chem. 2014, 10, 2539–2549, doi:10.3762/bjoc.10.265

• thionyl chloride [27]. These reaction conditions allowed the synthesis of α-brominated fatty acids 5 in a highly selective and efficient manner. Brominated AHL analogues 6a–f (dr 1:1) were prepared in acceptable yields by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)-mediated coupling of the

• acid 5 or 7 (1.5 equiv, 3 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (1.5 equiv, 0.58 g, 3 mmol). The mixture was stirred overnight at room temperature. The aqueous phase was extracted two times with ethyl acetate and the organic phase was washed with saturated aq NaHCO3 solution and brine

Synthesis of aromatic glycoconjugates. Building blocks for the construction of combinatorial glycopeptide libraries

• Markus Nörrlinger and
• Thomas Ziegler

Beilstein J. Org. Chem. 2014, 10, 2453–2460, doi:10.3762/bjoc.10.256

• , respectively, we chose 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDCI) instead of HBTU as the coupling reagent because the side product (1-(3-(dimethylamino)propyl)-3-ethylurea) released from EDCI was easily removed from the crude reaction mixture by washing with aqueous citric acid. The medium yields for

Synthesis of a bifunctional cytidine derivative and its conjugation to RNA for in vitro selection of a cytidine deaminase ribozyme

• Nico Rublack and
• Sabine Müller

Beilstein J. Org. Chem. 2014, 10, 1906–1913, doi:10.3762/bjoc.10.198

• -dimethylaminopropyl)carbodiimide hydrochloride (EDAC·HCl). Next, the 5'-O-TBDMS group was removed by stirring 11 in a mixture of THF/TFA/H2O (4:1:1, v/v/v) at 0 °C, and solely the 5'-O-deprotected cytidine derivative 12 was obtained in 94% yield (Figure 4). The long amino linker 13 was synthesized from hexaethylene

Clicked and long spaced galactosyl- and lactosylcalix[4]arenes: new multivalent galectin-3 ligands

• Silvia Bernardi,
• Paola Fezzardi,
• Gabriele Rispoli,
• Stefania E. Sestito,
• Francesco Peri,
• Francesco Sansone and
• Alessandro Casnati

Beilstein J. Org. Chem. 2014, 10, 1672–1680, doi:10.3762/bjoc.10.175

• to the concurrent formation of dicyclohexylurea (DCU), several purification steps were necessary to obtain pure calix[4]arene 8. The use of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) as an alternative coupling agent allowed us to isolate pure compound 8 in a more straightforward way and

Glycosystems in nanotechnology: Gold glyconanoparticles as carrier for anti-HIV prodrugs

• Fabrizio Chiodo,
• Marco Marradi,
• Javier Calvo,
• Eloisa Yuste and
• Soledad Penadés

Beilstein J. Org. Chem. 2014, 10, 1339–1346, doi:10.3762/bjoc.10.136

• thioacetate [31], was reacted with ABC and 3TC in DMF in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and 4-dimethylaminopyridine (DMAP) to obtain the ester derivative in ~75% yield. After purification, the protecting group of the thiol was removed with hydrazine acetate to give the

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

• species. Therefore, carbodiimide-based coupling reagents such as DCC (N,N'-dicyclohexylcarbodiimide) [20] and DIC (N,N'-diisopropylcarbodiimide) [53][54] were used and considered as the major activators for many decades. The susceptibility of this efficient activator to racemize led to the required

Silver and gold-catalyzed multicomponent reactions

• Giorgio Abbiati and
• Elisabetta Rossi

Beilstein J. Org. Chem. 2014, 10, 481–513, doi:10.3762/bjoc.10.46

• isoquinolinium-2-ylamide 43 undergoes a [3 + 2]-cycloaddition reaction with carbodiimide 54. Further intramolecular rearrangement yields the desired 1-(isoquinolin-1-yl)guanidine 55. Moreover, isoquinolinium-2-ylamides 43 can participate as 1,3-dipoles in [3 + 2]-cycloaddition reactions with in situ generated