Tunable microwave-assisted method for the solvent-free and catalyst-free peracetylation of natural products

• Manuela Oliverio,
• Paola Costanzo,
• Monica Nardi,
• Carla Calandruccio,
• Raffaele Salerno and
• Antonio Procopio

Beilstein J. Org. Chem. 2016, 12, 2222–2233, doi:10.3762/bjoc.12.214

• using acetic anhydride. So, starting from this statement and trading on our experience in catalyst-free reactions [27][28] and MW-assisted chemistry [29][30][31][32][33][34][35], we propose here a universal MW-assisted method for peracetylation of multifunctional compounds. The method is totally green

Biosynthesis of oxygen and nitrogen-containing heterocycles in polyketides

• Franziska Hemmerling and
• Frank Hahn

Beilstein J. Org. Chem. 2016, 12, 1512–1550, doi:10.3762/bjoc.12.148

• (Scheme 10) [50]. Their gene cluster contains a single epoxidase gene but no epoxide hydrolase, suggesting that the epoxidase is either multifunctional or that epoxide opening occurs spontaneously. The latter hypothesis is supported by the fact that allylic epoxides have been shown in synthetic

(Thio)urea-mediated synthesis of functionalized six-membered rings with multiple chiral centers

• Giorgos Koutoulogenis,
• Nikolaos Kaplaneris and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2016, 12, 462–495, doi:10.3762/bjoc.12.48

• were obtained in good to excellent yields (up to 96%) and moderate to excellent selectivities. In 2010, Chen, Xiao and co-workers described a domino sulfa-Michael–Michael reaction catalyzed by the novel multifunctional thiourea 171 (Scheme 56) [77]. The cascade is initiated by the addition of thiol 173

Application of 7-azaisatins in enantioselective Morita–Baylis–Hillman reaction

• Qing He,
• Gu Zhan,
• Wei Du and
• Ying-Chun Chen

Beilstein J. Org. Chem. 2016, 12, 309–313, doi:10.3762/bjoc.12.33

• allows a convenient approach to access multifunctional 3-hydroxy-7-aza-2-oxindoles with high enantiopurity (up to 94% ee). Other types of activated alkenes, such as acrylates and acrolein, could also be efficiently utilized. Keywords: 7-azaisatins; β-isocupreidine; bifunctional catalysis; maleimide; MBH

• were proven to be better electrophiles than the analogous isatins, and furnished a convenient protocol to enantio-enriched multifunctional 3-hydroxy-7-aza-2-oxindoles. Such substances might be further applied in organic synthesis for potential biological and pharmaceutical studies in the future

Facile synthesis of 4H-chromene derivatives via base-mediated annulation of ortho-hydroxychalcones and 2-bromoallyl sulfones

• Srinivas Thadkapally,
• Athira C. Kunjachan and
• Rajeev S. Menon

Beilstein J. Org. Chem. 2016, 12, 16–21, doi:10.3762/bjoc.12.3

•  1, path a). Bromoallyl sulfones 2a,b partake in a cesium carbonate-mediated formal vinylic substitution reaction with heteronucleophiles to afford valuable multifunctional building blocks [23]. For example, the reaction of 2a with 4-chlorophenol afforded the enol ether 3 in 84% yield (Scheme 1, path

Cross metathesis of unsaturated epoxides for the synthesis of polyfunctional building blocks

• Meriem K. Abderrezak,
• Kristýna Šichová,
• Nancy Dominguez-Boblett,
• Antoine Dupé,
• Zahia Kabouche,
• Christian Bruneau and
• Cédric Fischmeister

Beilstein J. Org. Chem. 2015, 11, 1876–1880, doi:10.3762/bjoc.11.201

• involving the cross metathesis of a commercially available epoxide-containing olefin with methyl acrylate and acrylonitrile and their subsequent transformations leading to multifunctional building blocks are reported. Results and Discussion Cross metathesis reactions involving electron-deficient olefins are

Star-shaped tetrathiafulvalene oligomers towards the construction of conducting supramolecular assembly

• Masahiko Iyoda and
• Masashi Hasegawa

Beilstein J. Org. Chem. 2015, 11, 1596–1613, doi:10.3762/bjoc.11.175

• functional dyes [22][23]. Furthermore, various multifunctional TTF-based supramolecular architectures have been designed and synthesized to realize molecular sensors, redox switches, multi-input systems for logic gates, electrochemically-driven conformational controls, molecular clips and tweezers, and redox

• oligomers with radially expanded structures can be expected to demonstrate multifunctional properties because a central core and TTF branches exhibit individual and/or cooperative functionalities [25]. For example, dendrimers composed of central benzenoid cores and TTF branches are cited as representative

• ]. Reflecting its strong π-donor ability, 1 was oxidized spontaneously in solution to afford 1•+ under ambient conditions. Multifunctional TTF-crown ether-substituted phthalocyanine (Pc) 2a and its copper(II) complex 2b were reported by Amabilino, Rowan, Nolte, and co-workers in 2005 [40]. The giant molecule 2a

Tetrathiafulvalene-based azine ligands for anion and metal cation coordination

• Awatef Ayadi,
• Aziz El Alamy,
• Olivier Alévêque,
• Magali Allain,
• Nabil Zouari,
• Mohammed Bouachrine and
• Abdelkrim El-Ghayoury

Beilstein J. Org. Chem. 2015, 11, 1379–1391, doi:10.3762/bjoc.11.149

• biggest challenges in materials science is devoted to the preparation of multifunctional molecular materials that can potentially exhibit, in solution and/or in solid state, synergy or coexistence between two or more different physical properties. In order to address this issue, many efforts have been

• coordination [37]. Herein we report the synthesis and electronic properties of two new multifunctional TTF-based azine ligands that integrate distinctive functional groups as depicted in Scheme 1 and thus capable of coordinating both metal cations as well as inorganic anions. The sensing studies for inorganic

• electrochemical behavior observed for L2 and its corresponding rhenium complex 3 indicate that this compounds are valuable candidates for the electrochemical formation of air-stable radical cation crystalline salts [16]. Conclusion Two multifunctional ligands which associate an electron-donating TTF unit with an

Exploring monovalent and multivalent peptides for the inhibition of FBP21-tWW

• Lisa Maria Henning,
• Sumati Bhatia,
• Miriam Bertazzon,
• Michaela Marczynke,
• Oliver Seitz,
• Rudolf Volkmer,
• Rainer Haag and
• Christian Freund

Beilstein J. Org. Chem. 2015, 11, 701–706, doi:10.3762/bjoc.11.80

• individual WW domains and with a KD of 150 μM to the tandem-WW1–WW2 construct. Secondly, this sequence was coupled to a hyperbranched polyglycerol (hPG) that allowed for the multivalent display on the surface of the dendritic polymer. This novel multifunctional hPG-peptide conjugate displayed a KD of 17.6 µM

Synthesis of carbohydrate-scaffolded thymine glycoconjugates to organize multivalency

• Anna K. Ciuk and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2015, 11, 668–674, doi:10.3762/bjoc.11.75

• install both branches on a carbohydrate scaffold. This would allow to favour the intramolecular [2 + 2] cycloaddition over an intermolecular reaction and moreover, a multifunctional carbohydrate scaffold facilitates further ligation or immobilization, respectively, of the final molecular construct. After

Linear-g-hyperbranched and cyclodextrin-based amphiphilic block copolymer as a multifunctional nanocarrier

• Yamei Zhao,
• Wei Tian,
• Guang Yang and
• Xiaodong Fan

Beilstein J. Org. Chem. 2014, 10, 2696–2703, doi:10.3762/bjoc.10.284

• Technology, School of Science, Northwestern Polytechnical University, Xi’an, 710072, P. R. China 10.3762/bjoc.10.284 Abstract In this paper, a novel, multifunctional polymer nanocarrier was designed to provide adequate volume for high drug loading, to afford a multiregion encapsulation ability, and to

• and quaternization reaction. The ABC then self-assembled into stable micelles with a core–shell structure in aqueous solution. These resulting micelles are multifunctional nanocarriers which possess higher drug loading capability due to the introduction of HBPCSi segments and β-CD moieties, and

• exhibit controlled drug release based on the diffusion release mechanism. The novel multifunctional nanocarrier may be applicable to produce highly efficient and specialized delivery systems for drugs, genes, and diagnostic agents. Keywords: amphiphilic block copolymer; cyclodextrin polymer

End group functionalization of poly(ethylene glycol) with phenolphthalein: towards star-shaped polymers based on supramolecular interactions

• Carolin Fleischmann,
• Hendrik Wöhlk and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 2263–2269, doi:10.3762/bjoc.10.235

• based on dipentaerythritol, which was converted into a multifunctional initiator for core first star polymer preparation approaches in previous studies [48][49], was synthesized according to a protocol previously developed in our group [50]. Dipentaerythritol was functionalized with six propargyl

Chiral phosphines in nucleophilic organocatalysis

• Yumei Xiao,
• Zhanhu Sun,
• Hongchao Guo and
• Ohyun Kwon

Beilstein J. Org. Chem. 2014, 10, 2089–2121, doi:10.3762/bjoc.10.218

• have excellent catalytic activities and enantioselectivities, only a few acyclic phosphines were effective. In this context, inspired by polyfunctional chiral small-molecule catalysts, particularly amino acid and thiourea-based systems [31][32], multifunctional chiral phosphines were constructed by

• accomplished using conventional chiral phosphines lacking hydrogen bonding moieties. Such multifunctional phosphines are readily accessible from simple chiral starting materials through a molecular building block approach, allowing combinatorial syntheses of new multifunctional chiral phosphines with diversity

• and, consequently, improving the probability of discovering an excellent catalyst. In this review, we divide chiral phosphines into three classes: cyclic phosphines (Figures 1–5), acyclic phosphines (Figure 6), and multifunctional acyclic phosphines (Figures 7 and 8). Generally, the cyclic phosphines

Investigations of thiol-modified phenol derivatives for the use in thiol–ene photopolymerizations

• Sebastian Reinelt,
• Monir Tabatabai,
• Urs Karl Fischer,
• Norbert Moszner,
• Andreas Utterodt and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 1733–1740, doi:10.3762/bjoc.10.180

• properties based on its rigid structure, we wish to present the synthesis of various multifunctional, hydrophobic thiol monomers all having in common a rigid phenol backbone and at least four primary aliphatic groups as well as the fact that they are ester-free liquids. Their behavior in thiol–ene

Carbohydrate PEGylation, an approach to improve pharmacological potency

• M. Eugenia Giorgi,
• Rosalía Agusti and
• Rosa M. de Lederkremer

Beilstein J. Org. Chem. 2014, 10, 1433–1444, doi:10.3762/bjoc.10.147

• increase solubility [8], prolong the in vivo action [9] or for targeting drug delivery [10] has been described. The potent anti-inflammatory drug dexamethasone was coupled to a multifunctional PEG, prepared by a click reaction, for treatment of rheumatoid arthritis [11]. A heterobifunctional PEG has been

Microwave-assisted Cu(I)-catalyzed, three-component synthesis of 2-(4-((1-phenyl-1H-1,2,3-triazol-4-yl)methoxy)phenyl)-1H-benzo[d]imidazoles

• Yogesh Kumar,
• Vijay Bahadur,
• Anil K. Singh,
• Virinder S. Parmar,
• Erik V. Van der Eycken and
• Brajendra K. Singh

Beilstein J. Org. Chem. 2014, 10, 1413–1420, doi:10.3762/bjoc.10.145

• entities in one molecule, have drawn the attention of medicinal chemists [14][15][16][17][18]. This logical approach is a promising path for those drug molecules which can effectively and selectively target multifunctional diseases. It has also been found that hybrid molecules are sometimes much more

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

• glyconanoparticles as a new multifunctional drug-delivery system in the therapy against HIV. Keywords: drug-delivery system; gold glyconanoparticles; HAART; HIV; multivalent glycosystems; reverse transcriptase inhibitors; Introduction Acquired immune deficiency syndrome (AIDS), caused by human immunodeficiency

• have been explored in biomedicine as multivalent and multifunctional scaffolds [12][13]. Thanks to their relative inertness and low toxicity gold nanoparticles have been widely explored to conjugate biomolecules on their surface, because the chemistry of their surface is easy to control [12]. The

• glyconanoparticles as a new multifunctional tool in the world of drug-delivery system against HIV. Experimental General methods: All chemicals were purchased as reagent grade from Sigma-Aldrich, except chloroauric acid (Strem Chemicals), and were used without further purification. NMR analyses were performed with a

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

• a cooperative effect [94], which means that albumin binding significantly increases until an appropriate fatty acid chain length is reached. In 1998, seven binding sites of this multifunctional transport protein were identified by Curry et al. using X-ray crystallographic studies [95]. Later on

Atherton–Todd reaction: mechanism, scope and applications

• Stéphanie S. Le Corre,
• Mathieu Berchel,
• Hélène Couthon-Gourvès,
• Jean-Pierre Haelters and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2014, 10, 1166–1196, doi:10.3762/bjoc.10.117

Site-selective covalent functionalization at interior carbon atoms and on the rim of circumtrindene, a C₃₆H₁₂ open geodesic polyarene

• Hee Yeon Cho,
• Ronald B. M. Ansems and
• Lawrence T. Scott

Beilstein J. Org. Chem. 2014, 10, 956–968, doi:10.3762/bjoc.10.94

• explored immediately following the discovery of methods for bulk preparation of fullerenes in 1990 [28]. Within the first few years, several covalent functionalization sequences were introduced that became widely used for the construction of multifunctional architectures with C60 as an integral building

Addition of H-phosphonates to quinine-derived carbonyl compounds. An unexpected C9 phosphonate–phosphate rearrangement and tandem intramolecular piperidine elimination

• Łukasz Górecki,
• Artur Mucha and
• Paweł Kafarski

Beilstein J. Org. Chem. 2014, 10, 883–889, doi:10.3762/bjoc.10.85

• with trimethylamine oxide [31]. As the oxide also released the borane–quinuclidine complex at elevated temperature the free alcohol was obtained in a satisfactory yield. This alcohol was subjected to Swern oxidation, recommended for multifunctional compounds [32], to produce the target aldehyde 8 in 65

Metal and metal-free photocatalysts: mechanistic approach and application as photoinitiators of photopolymerization

• Jacques Lalevée,
• Sofia Telitel,
• Pu Xiao,
• Marc Lepeltier,
• Frédéric Dumur,
• Fabrice Morlet-Savary,
• Didier Gigmes and
• Jean-Pierre Fouassier

Beilstein J. Org. Chem. 2014, 10, 863–876, doi:10.3762/bjoc.10.83

• ][52][53][54][55]) in formulations containing multifunctional synthetic epoxides, acrylates, monomers/oligomers or epoxide/acrylate blends (renewable raw or modified materials are usable to some extent) with lights extending from the UV to the red, using polychromatic or monochromatic light sources

• ) [66]. All these reactions allowed the radical photopolymerization of formulations containing multifunctional synthetic acrylates using UV to red lights delivered by low intensity sources. A new PIC based on a panchromatic iridium complex and the associated performance in the photopolymerization area

Total synthesis of (+)-grandiamide D, dasyclamide and gigantamide A from a Baylis–Hillman adduct: A unified biomimetic approach

• Andivelu Ilangovan and
• Shanmugasundar Saravanakumar

Beilstein J. Org. Chem. 2014, 10, 127–133, doi:10.3762/bjoc.10.9

• additional functional groups on them by replacing the starting materials by activated alkenes and aldehydes. Various multifunctional molecules including natural products have already been successfully synthesized using the Baylis–Hillman adducts [9]. Structural features of grandiamide D, gigantamide A

Stereoselectively fluorinated N-heterocycles: a brief survey

• Xiang-Guo Hu and
• Luke Hunter

Beilstein J. Org. Chem. 2013, 9, 2696–2708, doi:10.3762/bjoc.9.306

• . Instead, we will focus on two recent developments in deoxyfluorination methods that are particularly relevant to N-heterocyclic targets. Late stage deoxyfluorination is an attractive method for synthesising multifunctional fluorinated N-heterocycles, but mild and selective reagents are required if this is

• . Fluorinated miglitol analogues, and their inhibitory activity towards yeast α-glycosidase. Analogues of isofagomine (31) have different pKaH values, and therefore exhibit maximal β-glucosidase inhibition at different pH values. Late stage deoxyfluorination in the synthesis of multifunctional N-heterocycles

The conjugation of nonsteroidal anti-inflammatory drugs (NSAID) to small peptides for generating multifunctional supramolecular nanofibers/hydrogels

• Jiayang Li,
• Yi Kuang,
• Junfeng Shi,
• Yuan Gao,
• Jie Zhou and
• Bing Xu

Beilstein J. Org. Chem. 2013, 9, 908–917, doi:10.3762/bjoc.9.104

• -delivery; hydrogel; multifunctional; nanofibers; NSAID; self-assembly; supramolecular; topical use; Introduction This article reports the design, synthesis, and characterization of hydrogelators made of non-steroidal anti-inflammatory drugs (NSAID) and small peptides for the development of multifunctional