Hindered aryl bromides for regioselective palladium-catalysed direct arylation at less favourable C5-carbon of 3-substituted thiophenes

• Rongwei Jin,
• Charles Beromeo Bheeter and
• Henri Doucet

Beilstein J. Org. Chem. 2014, 10, 1239–1245, doi:10.3762/bjoc.10.123

• different aryl units. Keywords: aryl bromides; atom economy; C–H bond activation; palladium; regioselectivity; thiophenes; Introduction As thiophenes bearing aryl substituents are known to be present in several bioactive molecules and are used as precursors of materials, the regioselective introduction of

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

• peptide sequence for analytical investigations (Figure 4). These tools can be spin and radioactive labels, bioactive molecules (such as biotin) or fluorescent dyes. The paramagnetic substance TOAC (2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid) (Figure 5) was manually coupled to NPY

Direct C–H trifluoromethylation of di- and trisubstituted alkenes by photoredox catalysis

• Ren Tomita,
• Yusuke Yasu,
• Takashi Koike and
• Munetaka Akita

Beilstein J. Org. Chem. 2014, 10, 1099–1106, doi:10.3762/bjoc.10.108

• catalysis; radical reaction; trifluoromethylation; Introduction The trifluoromethyl (CF3) group is a useful structural motif in many bioactive molecules as well as functional organic materials [1][2][3][4][5][6]. Thus, the development of new methodologies for highly efficient and selective incorporation of

Aza-Diels–Alder reaction between N-aryl-1-oxo-1H-isoindolium ions and tert-enamides: Steric effects on reaction outcome

• Amitabh Jha,
• Ting-Yi Chou,
• Zainab ALJaroudi,
• Bobby D. Ellis and
• T. Stanley Cameron

Beilstein J. Org. Chem. 2014, 10, 848–857, doi:10.3762/bjoc.10.81

• , 1375, 1269, 758 cm−1; HRMS m/z: [M + Na]+ calcd for C20H17FN2O2Na, 359.1166; found, 359.1149. Pyridoisoindole frameworks (highlighted) in bioactive molecules and compounds under present investigation (series 1–3). ORTEP diagrams and 2D structures for the isoindolo[2,1-a]quinolone derivatives 1b, 1h and

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

• a tool to probe the importance of hydrogen bonding in bioactive molecules; and we will observe how fluorine can affect the basicity of N-heterocycles. Finally, we will survey some of the various ways in which stereoselectively fluorinated N-heterocycles can be synthesised. Throughout, it will become

• primarily been considering fluorine as a replacement for hydrogen in N-heterocycles. However a new vista opens up if we consider fluorine as a replacement for the hydroxy group in bioactive molecules. 4. Fluorine can serve as a tool to probe the importance of hydrogen bonding The replacement of a hydroxy

A one-pot synthesis of 3-trifluoromethyl-2-isoxazolines from trifluoromethyl aldoxime

• Raoni S. B. Gonçalves,
• Michael Dos Santos,
• Guillaume Bernadat,
• Danièle Bonnet-Delpon and
• Benoit Crousse

Beilstein J. Org. Chem. 2013, 9, 2387–2394, doi:10.3762/bjoc.9.275

• frequently found in natural products [1][2][3][4], bioactive molecules [5][6] (Figure 1) and can be used as bioisosteric transformations of amide bonds in order to provide metabolically stable and more active derivatives [7][8][9][10][11]. Moreover, 2-isoxazolines can be cleaved under various conditions to

• supply a variety of organic functionalities including γ-amino alcohols [12], β-amino acids [13], β-hydroxy ketones [14][15] and β-hydroxy nitriles [14][15]. Fluorinated compounds play a central role in different branches of chemistry [16]. The incorporation of a fluorine atom into bioactive molecules

• different fluorinated building blocks was demonstrated by the easy ring opening of these intermediates with NaBH4 and NiCl2, yielding the corresponding trifluoromethylated γ-amino alcohol. Example of bioactive molecules bearing the 2-isoxazoline nucleus. Dimerization and isomerization products from nitrile

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

• [59][60], this work contributes to the development of bioactive molecules that have dual or multiple roles, for example, as therapeutic agents and delivery carriers [61][62]. Results and Discussion Synthesis Scheme 2 shows the typical synthetic route of the conjugates of NSAID and small peptides

• hydrogelation of other bioactive molecules. By providing useful insight for design of the NSAID hydrogelators, this approach contributes to the development of bioactive molecules that have dual or multiple roles, such as hydrogelators and therapeutic agents. Optical images of the hydrogels formed by (A) 1a (0.8

N-Heterocyclic carbene–palladium catalysts for the direct arylation of pyrrole derivatives with aryl chlorides

• Ismail Özdemir,
• Nevin Gürbüz,
• Nazan Kaloğlu,
• Öznur Doğan,
• Murat Kaloğlu,
• Christian Bruneau and
• Henri Doucet

Beilstein J. Org. Chem. 2013, 9, 303–312, doi:10.3762/bjoc.9.35

• important research area in organic synthesis as such motives are known to be present in several bioactive molecules, such as Atorvastatin, which is used for lowering blood cholesterol, Fendosal, which is an anti-inflammatory agent, or Tanaproget, which is a progesterone-receptor agonist (Figure 1). The

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

• Wilhelms University of Bonn, Germany Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany 10.3762/bjoc.9.7 Abstract Sugar moieties are present in a wide range of bioactive molecules. Thus, having versatile and

Mechanochemistry assisted asymmetric organocatalysis: A sustainable approach

• Pankaj Chauhan and
• Swapandeep Singh Chimni

Beilstein J. Org. Chem. 2012, 8, 2132–2141, doi:10.3762/bjoc.8.240

• various bioactive molecules [28]. Among different organocatalysts used for asymmetric aldol reactions, proline and its derivatives emerged as powerful catalysts for the enamine activation of donor aldehyde or ketone. Bolm’s group reported a solvent-free asymmetric organocatalytic aldol reaction under ball

An efficient access to the synthesis of novel 12-phenylbenzo[6,7]oxepino[3,4-b]quinolin-13(6H)-one derivatives

• Wentao Gao,
• Guihai Lin,
• Yang Li,
• Xiyue Tao,
• Rui Liu and
• Lianjie Sun

Beilstein J. Org. Chem. 2012, 8, 1849–1857, doi:10.3762/bjoc.8.213

• , our research team has been interested in the development of efficient synthesis for the quinoline-based bioactive molecules [32][33][34][35][36][37]. Thus, in connection with our continuing interest in the synthesis of highly valuable quinoline compounds, we are actively involved in diversifying our

Cyanoethylation of the glucans dextran and pullulan: Substitution pattern and formation of nanostructures and entrapment of magnetic nanoparticles

• Kathrin Fiege,
• Heinrich Lünsdorf,
• Sevil Atarijabarzadeh and
• Petra Mischnick

Beilstein J. Org. Chem. 2012, 8, 551–566, doi:10.3762/bjoc.8.63

• bind iron oxide particles additionally. This observation could indicate that some cyanoethyl groups are available for further transformation of the outer sugar shell, e.g., amino functionalization followed by coupling with bioactive molecules. In conclusion, it was shown, that the magnetic iron cores

Computational evidence for intramolecular hydrogen bonding and nonbonding X···O interactions in 2'-haloflavonols

• Tânia A. O. Fonseca,
• Matheus P. Freitas,
• Rodrigo A. Cormanich,
• Teodorico C. Ramalho,
• Cláudio F. Tormena and
• Roberto Rittner

Beilstein J. Org. Chem. 2012, 8, 112–117, doi:10.3762/bjoc.8.12

• ubiquitous than one imagines and can determine crystal structures [10] and the binding of biological molecules [11] and may possibly be the main forces in determining conformational preferences in molecular systems. 2'-Haloflavonols are important compounds with widespread use as bioactive molecules

First synthesis of 2-(benzofuran-2-yl)-6,7-methylene dioxyquinoline-3-carboxylic acid derivatives

• Wentao Gao,
• Jia Liu,
• Yun Jiang and
• Yang Li

Beilstein J. Org. Chem. 2011, 7, 210–217, doi:10.3762/bjoc.7.28

• intermediates which may be responsible for the observed antitumor activity of lignans [23][24]. The presence of the methylenedioxy moiety in some other bioactive molecules drastically alters their pharmacological properties. For example, among the tested 2-phenylquinolin-4-ones (2-PQs) with potent cytotoxicity

Amphiphilic dendritic peptides: Synthesis and behavior as an organogelator and liquid crystal

• Baoxiang Gao,
• Hongxia Li,
• Defang Xia,
• Sufang Sun and
• Xinwu Ba

Beilstein J. Org. Chem. 2011, 7, 198–203, doi:10.3762/bjoc.7.26

• display a wide range of physical properties often exceeding those of synthetic polymers [4][5]. Peptide-amphiphiles (PAs) represent an attractive class of bioactive molecules as they self-assemble into a variety of nanostructures, many of which have promising biological activity due to the exposed peptide

An easy assembled fluorescent sensor for dicarboxylates and acidic amino acids

• Xiao-bo Zhou,
• Yuk-Wang Yip,
• Wing-Hong Chan and
• Albert W. M. Lee

Beilstein J. Org. Chem. 2011, 7, 75–81, doi:10.3762/bjoc.7.11

• roles of anions in many chemical and biological processes [1][2][3][4][5]. Being the key structural moieties of many bioactive molecules such as amino acids and proteins, dicarboxylates are one of the most attractive targets for anion recognition and sensing. In addition, dicarboxylates are essential

Pd/C-mediated synthesis of α-pyrone fused with a five-membered nitrogen heteroaryl ring: A new route to pyrano[4,3-c]pyrazol-4(1H)-ones

• Dhilli Rao Gorja,
• Venkateswara Rao Batchu,
• Ashok Ettam and
• Manojit Pal

Beilstein J. Org. Chem. 2009, 5, No. 64, doi:10.3762/bjoc.5.64

• bioactive molecules, the pyrazole framework plays an important role in pharmaceutical research. We therefore believe that the present methodology and the product pyranopyrazol-4-one being a potential synthon for more complex heterocycles may find wide applications in organic synthesis, especially in

An asymmetric synthesis of all stereoisomers of piclavines A1-4 using an iterative asymmetric dihydroxylation

• Yukako Saito,
• Naoki Okamoto and
• Hiroki Takahata

Beilstein J. Org. Chem. 2007, 3, No. 37, doi:10.1186/1860-5397-3-37

• dihydroxylation with enantiomeric enhancement. Background Indolizidine units are frequently found in many natural products and designed bioactive molecules. [1] Among these alkaloids, piclavines A1-4 (Figure 1), extracted from the tunicate Clavelina picta and the first indolizidine alkaloids to be found in the