Synthesis and selected transformations of 2-unsubstituted 1-(adamantyloxy)imidazole 3-oxides: straightforward access to non-symmetric 1,3-dialkoxyimidazolium salts

• Grzegorz Mlostoń,
• Małgorzata Celeda,
• Katarzyna Urbaniak,
• Marcin Jasiński,
• Vladyslav Bakhonsky,
• Peter R. Schreiner and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2019, 15, 497–505, doi:10.3762/bjoc.15.43

• , alkoxyamines are known not only as bioactive compounds [19][20] but also as important initiators of polymerization processes that have been extensively studied in the recent decade [21]. Among alkoxyamines, adamantyloxyamine (4) occupies a prominent position, and for that reason it was selected for experiments

• alkaloids, which found wide application in some regions as food-stuff and medical supply [33]. The method described in the present study opens a straightforward access to their benzyloxy analogues, potentially bioactive compounds, which have not been known yet. Experimental General information: Solvents and

Thiol-free chemoenzymatic synthesis of β-ketosulfides

• Adrián A. Heredia,
• Martín G. López-Vidal,
• Marcela Kurina-Sanz,
• Fabricio R. Bisogno and
• Alicia B. Peñéñory

Beilstein J. Org. Chem. 2019, 15, 378–387, doi:10.3762/bjoc.15.34

• role as precursors in the synthesis of bioactive compounds [13][26][27], substrates for multicomponent reactions [28], and lately, have successfully been applied in polymer photodecoration [29][30]. They can easily be reduced into chiral hydroxy derivatives [31] and properly oxidised at sulfur to

Sigmatropic rearrangements of cyclopropenylcarbinol derivatives. Access to diversely substituted alkylidenecyclopropanes

• Guillaume Ernouf,
• Jean-Louis Brayer,
• Christophe Meyer and
• Janine Cossy

Beilstein J. Org. Chem. 2019, 15, 333–350, doi:10.3762/bjoc.15.29

• alkylidenecyclopropanes are also synthetically useful [1][2][3][4][5][6]. The importance of this latter class of transformations is obviously related to the widespread occurrence of cyclopropanes in natural and/or bioactive compounds [7][8] and the great interest of the cyclopropyl core in new drugs development [9

Asymmetric synthesis of a high added value chiral amine using immobilized ω-transaminases

• Antonella Petri,
• Valeria Colonna and
• Oreste Piccolo

Beilstein J. Org. Chem. 2019, 15, 60–66, doi:10.3762/bjoc.15.6

• and in particular compounds with an amino functional group such as 3-aminopiperidine are valuable intermediates for the production of a large number of bioactive compounds with pharmacological properties. In this paper, the synthesis of both enantiomers of 3-amino-1-Boc-piperidine by amination of the

Molecular iodine-catalyzed one-pot multicomponent synthesis of 5-amino-4-(arylselanyl)-1H-pyrazoles

• Camila S. Pires,
• Daniela H. de Oliveira,
• Maria R. B. Pontel,
• Jean C. Kazmierczak,
• Roberta Cargnelutti,
• Diego Alves,
• Raquel G. Jacob and
• Ricardo F. Schumacher

Beilstein J. Org. Chem. 2018, 14, 2789–2798, doi:10.3762/bjoc.14.256

• importance in bioactive compounds, pharmaceuticals, and as chemical intermediates for organic and inorganic synthesis [1][2]. As a consequence, the development of efficient and practical methods for C–Se bond formation is still a promising field of research in organic chemistry. Despite the several number of

Synthesis of a tyrosinase inhibitor by consecutive ethenolysis and cross-metathesis of crude cashew nutshell liquid

• Jacqueline Pollini,
• Valentina Bragoni and
• Lukas J. Gooßen

Beilstein J. Org. Chem. 2018, 14, 2737–2744, doi:10.3762/bjoc.14.252

• ]. A limited number of derivatizations of anacardic acid are reported by now, including the synthesis of lactones [18][19][20], sulfonamides [21] or hydrazones [22], typically bioactive compounds though with low commercial value. However, several studies suggest that anacardic acid and its derivatives

Some mechanistic aspects regarding the Suzuki–Miyaura reaction between selected ortho-substituted phenylboronic acids and 3,4,5-tribromo-2,6-dimethylpyridine

• Piotr Pomarański,
• Piotr Roszkowski,
• Jan K. Maurin,
• Armand Budzianowski and
• Zbigniew Czarnocki

Beilstein J. Org. Chem. 2018, 14, 2384–2393, doi:10.3762/bjoc.14.214

• selectivity using a differently ortho-substituted phenylbornic acid was observed. Keywords: arylpyridines; atropisomerism; cross-coupling; palladium; Suzuki–Miyaura reaction; Introduction Axially chiral biaryls not only subsist in many classes of natural and bioactive compounds [1][2] but also are an

Synthesis of 1,4-imino-L-lyxitols modified at C-5 and their evaluation as inhibitors of GH38 α-mannosidases

• Maroš Bella,
• Sergej Šesták,
• Ján Moncoľ,
• Miroslav Koóš and
• Monika Poláková

Beilstein J. Org. Chem. 2018, 14, 2156–2162, doi:10.3762/bjoc.14.189

• ; inhibitors; pyrrolidines; synthesis; Introduction Carbohydrates as chiral templates for a construction of bioactive compounds are of steady interest in medicinal chemistry [1][2][3]. The polyfunctional nature of carbohydrate units offers many possibilities for the design of a wide variety of new compounds

• . Moreover, various desired substituents can be selectively appended to any required position of the carbohydrate unit. This leads to a preparation of mimetics that meet the requirements of metabolically more stable bioactive compounds. During the years, many scaffolds based on monosaccharides [4

• ], disaccharides or higher oligosaccharides [5][6] as well as multivalent [7][8] carbohydrate units have been developed. These glycomimetics and glycopeptides have also found applications as bioactive compounds [9][10]. One group of the scaffolds includes iminosugars [11][12] as analogues of the monosaccharides

Rhodium-catalyzed C–H functionalization of heteroarenes using indoleBX hypervalent iodine reagents

• Erwann Grenet,
• Ashis Das,
• Paola Caramenti and
• Jérôme Waser

Beilstein J. Org. Chem. 2018, 14, 1208–1214, doi:10.3762/bjoc.14.102

• also omnipresent in bioactive compounds [2]. It can be directly bound to other heterocycles, such as a dihydropyrazidinone in hamacanthine A (4) (Figure 1) [3]. Due to their occurrence in biologically active compounds, it is therefore attractive to develop new methods to functionalize pyridinones. The

• building blocks in the search for new bioactive compounds. Results and Discussion We started the studies on C–H indolation with the optimization of the reactions conditions (Table 1) for the coupling of [1,2'-bipyridin]-2-one (5a) with Me-indoleBX 6a, easily obtained from commercially available 1

• separated and the aqueous layer was extracted twice with DCM (5 mL). The organic layers were combined, dried over magnesium sulfate dehydrate, filtered and concentrated under reduced pressure. The crude residue was purified by preparative TLC using DCM/MeOH to afford the pure desired compound. Bioactive

Fluorocyclisation via I(I)/I(III) catalysis: a concise route to fluorinated oxazolines

• Felix Scheidt,
• Christian Thiehoff,
• Gülay Yilmaz,
• Stephanie Meyer,
• Constantin G. Daniliuc,
• Gerald Kehr and
• Ryan Gilmour

Beilstein J. Org. Chem. 2018, 14, 1021–1027, doi:10.3762/bjoc.14.88

• . Selected examples of bioactive compounds containing the 2-oxazoline motif. The catalytic difluorination of alkenes (top) and the proposed fluorocyclisation via the same I(I)/I(III) manifold (bottom). Substrate scope. aReaction conducted on 1 mmol scale. bReaction time increased to 40 hours. cReaction time

Investigations towards the stereoselective organocatalyzed Michael addition of dimethyl malonate to a racemic nitroalkene: possible route to the 4-methylpregabalin core structure

• Denisa Vargová,
• Rastislav Baran and
• Radovan Šebesta

Beilstein J. Org. Chem. 2018, 14, 553–559, doi:10.3762/bjoc.14.42

• stereoselective synthesis of bioactive compounds [1][2][3]. In particular, stereoselective conversions of nitro compounds served in many syntheses of pharmaceuticals [4]. Derivatives of γ-aminobutyric acid are an important class of medicines targeting problems with the central nervous system, such as pains

Synthesis of fluoro-functionalized diaryl-λ³-iodonium salts and their cytotoxicity against human lymphoma U937 cells

• Prajwalita Das,
• Etsuko Tokunaga,
• Hidehiko Akiyama,
• Hiroki Doi,
• Norimichi Saito and
• Norio Shibata

Beilstein J. Org. Chem. 2018, 14, 364–372, doi:10.3762/bjoc.14.24

• ]. Hypervalent iodine compounds have been receiving a lot of attention lately due to their varied applications in organic synthesis [33][34][35][36][37][38][39][40]. A wide range of bioactive compounds make use of diaryliodonium reagents as a part of their synthesis [41][42][43]. On the other hand, there are

Nucleophilic fluoroalkylation/cyclization route to fluorinated phthalides

• Masanori Inaba,
• Tatsuya Sakai,
• Shun Shinada,
• Tsuyuka Sugiishi,
• Yuta Nishina,
• Norio Shibata and
• Hideki Amii

Beilstein J. Org. Chem. 2018, 14, 182–186, doi:10.3762/bjoc.14.12

• synthesis of useful bioactive compounds. There is a growing interest in the usefulness of phthalides and their derivatives. Organofluorine compounds often show attractive physical, chemical, and biological properties and are widely used in many fields, such as pharmaceuticals, agrochemicals, and materials

Progress in copper-catalyzed trifluoromethylation

• Guan-bao Li,
• Chao Zhang,
• Chun Song and
• Yu-dao Ma

Beilstein J. Org. Chem. 2018, 14, 155–181, doi:10.3762/bjoc.14.11

• . Although phenols were widely used building blocks in bioactive compounds, only a few examples introducing a CF3 have been reported. In 2015, the group of Hamashima [52] achieved a direct C–H trifluoromethylation of phenol derivatives with high regioselectivity. The CF3 was selectively incorporated into the

Photocatalytic formation of carbon–sulfur bonds

• Alexander Wimmer and
• Burkhard König

Beilstein J. Org. Chem. 2018, 14, 54–83, doi:10.3762/bjoc.14.4

• Ananikov and co-workers (Scheme 9) [39]. Their aim was to develop a photocatalytic method that is applicable for the industrial synthesis of pharmaceuticals or bioactive compounds. Using metal-based photocatalysts may leave traces of metal impurities in the crude product causing elaborative purification

The photodecarboxylative addition of carboxylates to phthalimides as a key-step in the synthesis of biologically active 3-arylmethylene-2,3-dihydro-1H-isoindolin-1-ones

• Ommid Anamimoghadam,
• Saira Mumtaz,
• Anke Nietsch,
• Gaetano Saya,
• Cherie A. Motti,
• Jun Wang,
• Peter C. Junk,
• Ashfaq Mahmood Qureshi and
• Michael Oelgemöller

Beilstein J. Org. Chem. 2017, 13, 2833–2841, doi:10.3762/bjoc.13.275

• local anesthetics: (a) a lipophilic aromatic ring, (b) an amide (or ester) linker, and (c) a terminal tertiary amine [9]. The original synthesis of these bioactive compounds involved a Perkin condensation followed by an amination reaction. An alternative pathway to AL-12B has been described by Couture

CF₃SO₂X (X = Na, Cl) as reagents for trifluoromethylation, trifluoromethylsulfenyl-, -sulfinyl- and -sulfonylation. Part 1: Use of CF₃SO₂Na

• Hélène Guyon,
• Hélène Chachignon and
• Dominique Cahard

Beilstein J. Org. Chem. 2017, 13, 2764–2799, doi:10.3762/bjoc.13.272

• , it was essential to have a phenyl as a substituent in order to get good yields. A radical mechanism was proposed but the role of oxygen was not discussed. Aminoquinoline derivatives are found in naturally occurring and synthetic bioactive compounds, most notable for their antimalarial activity. So

Asymmetric synthesis of propargylamines as amino acid surrogates in peptidomimetics

• Matthias Wünsch,
• David Schröder,
• Tanja Fröhr,
• Lisa Teichmann,
• Sebastian Hedwig,
• Nils Janson,
• Clara Belu,
• Jasmin Simon,
• Shari Heidemeyer,
• Philipp Holtkamp,
• Jens Rudlof,
• Lennard Klemme,
• Alessa Hinzmann,
• Beate Neumann,
• Hans-Georg Stammler and
• Norbert Sewald

Beilstein J. Org. Chem. 2017, 13, 2428–2441, doi:10.3762/bjoc.13.240

• , these propargylamines have been frequently used as precursors for the synthesis of diverse bioactive compounds. Their conversion into triazoles is best investigated, since triazoles as amide bond surrogates are found in several inhibitors of proteases such as cathepsin S [1][2][3][4][5][6], cysteine

Fluorination of some highly functionalized cycloalkanes: chemoselectivity and substrate dependence

• Attila Márió Remete,
• Melinda Nonn,
• Santos Fustero,
• Matti Haukka,
• Ferenc Fülöp and
• Loránd Kiss

Beilstein J. Org. Chem. 2017, 13, 2364–2371, doi:10.3762/bjoc.13.233

• amino acids and their analogous derivatives have gained considerable interest in pharmaceutical chemistry as bioactive compounds. Some derivatives (e.g., peramivir, oseltamivir or laninamivir) are known as antiviral drugs [19][20][21][22], while other cyclopentane β-amino acids (e.g., icofungipen

Phosphonic acid: preparation and applications

• Charlotte M. Sevrain,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2017, 13, 2186–2213, doi:10.3762/bjoc.13.219

• new bioactive compounds [8], will not be detailed in this review which is focused on the chemical way of producing phosphonic acids. Of note, this review is not an exhaustive list of all the phosphonic acids synthesized over the last 20 years but a selection of examples that aim to illustrate the most

Preparation of imidazo[1,2-a]-N-heterocyclic derivatives with gem-difluorinated side chains

• Layal Hariss,
• Kamal Bou Hadir,
• Mirvat El-Masri,
• Thierry Roisnel,
• René Grée and
• Ali Hachem

Beilstein J. Org. Chem. 2017, 13, 2115–2121, doi:10.3762/bjoc.13.208

• prepared in fair yields by the reaction of gem-difluoroenones with aminopyridines, -pyrimidines and -pyridazines. Condensed heterocycles of this type play an important role as key core structures of various bioactive compounds. Further, starting with a chloroimidazopyridazine derivative, Pd-catalyzed

Conformational impact of structural modifications in 2-fluorocyclohexanone

• Francisco A. Martins,
• Josué M. Silla and
• Matheus P. Freitas

Beilstein J. Org. Chem. 2017, 13, 1781–1787, doi:10.3762/bjoc.13.172

• Francisco A. Martins Josue M. Silla Matheus P. Freitas Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, MG, Brazil 10.3762/bjoc.13.172 Abstract 2-Haloketones are building blocks that combine physical, chemical and biological features of materials and bioactive compounds

Sustainable synthesis of 3-substituted phthalides via a catalytic one-pot cascade strategy from 2-formylbenzoic acid with β-keto acids in glycerol

• Lina Jia and
• Fuzhong Han

Beilstein J. Org. Chem. 2017, 13, 1425–1429, doi:10.3762/bjoc.13.139

• reaction; phthalide; Introduction The phthalides, also known as isobenzofuran-1(3H)-ones, are an important class of heterocycles which are of continued interest for chemists [1][2]. 3-Substituted phthalides, which are recognized as versatile building blocks found in a large number of bioactive compounds

A speedy route to sterically encumbered, benzene-fused derivatives of privileged, naturally occurring hexahydropyrrolo[1,2-b]isoquinoline

• Olga Bakulina,
• Alexander Ivanov,
• Vitalii Suslonov,
• Dmitry Dar’in and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2017, 13, 1413–1424, doi:10.3762/bjoc.13.138

• ]isoquinoline core via the CCR and its occurrence in natural and synthetic bioactive compounds. Indolenine substrates 9a–t investigated in this work. aPrepared for the first time (the rest are known compounds, see Experimental section). bUnstable to isolation; was taken in the CCR step as a solution in

Aqueous semisynthesis of C-glycoside glycamines from agarose

• Juliana C. Cunico Dallagnol,
• Alexandre Orsato,
• Diogo R. B. Ducatti,
• Miguel D. Noseda,
• Maria Eugênia R. Duarte and
• Alan G. Gonçalves

Beilstein J. Org. Chem. 2017, 13, 1222–1229, doi:10.3762/bjoc.13.121

• employed in drug discovery. A part of our group has utilized this type of approach for the synthesis of dihydropyridine glycoconjugates [9] and antiviral sulfated alkylglycosides [10]. In an effort to amplify the utility of AnGal as a starting material for the synthesis of bioactive compounds, we have