A flow reactor setup for photochemistry of biphasic gas/liquid reactions

• Josef Schachtner,
• Patrick Bayer and
• Axel Jacobi von Wangelin

Beilstein J. Org. Chem. 2016, 12, 1798–1811, doi:10.3762/bjoc.12.170

• to oxidation chemistry of utmost sustainability. Under irradiation in the presence of a sensitizer, singlet oxygen can easily be generated from the triplet ground state. Several applications of such photooxidations to chemical synthesis have been reported [71][72][73], in recent years most

Copper-catalyzed [3 + 2] cycloaddition of (phenylethynyl)di-p-tolylstibane with organic azides

• Mizuki Yamada,
• Mio Matsumura,
• Yuki Uchida,
• Masatoshi Kawahata,
• Yuki Murata,
• Naoki Kakusawa,
• Kentaro Yamaguchi and
• Shuji Yasuike

Beilstein J. Org. Chem. 2016, 12, 1309–1313, doi:10.3762/bjoc.12.123

• -triazoles (Bi), which could be employed as versatile building blocks in chemical synthesis [24]. One drawback of the Cu-catalyzed cycloaddition of alkynylbismuthanes is the requirement of alkyne derivatives based on the phenothiabismuthane 5,5-dioxide framework for stabilization. The utility of

Synthesis of a deuterated probe for the confocal Raman microscopy imaging of squalenoyl nanomedicines

• Eric Buchy,
• Branko Vukosavljevic,
• Maike Windbergs,
• Dunja Sobot,
• Camille Dejean,
• Simona Mura,
• Patrick Couvreur and
• Didier Desmaële

Beilstein J. Org. Chem. 2016, 12, 1127–1135, doi:10.3762/bjoc.12.109

• , its coupling with gemcitabine and the Raman spectra of the deuterated GemSQ nanoassemblies, opening the way to perform intracellular imaging of squalenoyl nanomedicine (Figure 1). Results and Discussion Chemical synthesis of squalenic acid-d6 and GemSQ-d6 conjugate In a first approach we decided to

Efficient syntheses of climate relevant isoprene nitrates and (1R,5S)-(−)-myrtenol nitrate

• Sean P. Bew,
• Glyn D. Hiatt-Gipson,
• Graham P. Mills and
• Claire E. Reeves

Beilstein J. Org. Chem. 2016, 12, 1081–1095, doi:10.3762/bjoc.12.103

• , reinforces the need for chemical synthesis studies on the formation of climate relevant organic nitrates [14]. Even though the atmospheric synthesis of structure diverse C5-IPNs, i.e., 4–10 is thought to be efficient, i.e., up to 15% yield [15] what is not currently fully understood is the mechanism or

Biosynthesis of α-pyrones

• Till F. Schäberle

Beilstein J. Org. Chem. 2016, 12, 571–588, doi:10.3762/bjoc.12.56

• isolated from Leptosphaeria maculans and named phomapyrone A, as well as from the mediterranean ascoglossan mollusc Ercolania funereal, described as cyercene [51]. Phomenin A displayed phytotoxicity at a concentration of 100 µg/mL. Chemical synthesis approaches enabled then to investigate many more α

• agronomically important pathogens, e.g., complete inhibition of Magnaporthe grisea and Phaeosphaeria nodorum at 67 µg/mL, and Botrytis cinerea was inhibited at 200 µg/mL. 2 Biosynthesis Even though the α-pyrones possessing interesting activities were in the focus of chemical synthesis approaches for a long time

A selective and mild glycosylation method of natural phenolic alcohols

• Mária Mastihubová and
• Monika Poláková

Beilstein J. Org. Chem. 2016, 12, 524–530, doi:10.3762/bjoc.12.51

• had to be optimized. The current paper deals with an efficient, safe and uniform chemical synthesis of various p-hydroxyarylalkyl glycosides, including compounds 1–3. Results and Discussion Preparation of aglycones The synthesis of the appropriate aglycones 6a–c was commenced from readily available

Mycothiol synthesis by an anomerization reaction through endocyclic cleavage

• Shino Manabe and
• Yukishige Ito

Beilstein J. Org. Chem. 2016, 12, 328–333, doi:10.3762/bjoc.12.35

• -containing lincosamide antibiotic [19]. Due to the limited availability of MSH from M. smegmatis cell culture (<1.5 mg of MSH from 1 L culture) [20], the chemical synthesis of MSH is highly desired. Bewley et al. and Lee and Rosazza independently reported the synthesis of MSH and determined the absolute

Synthesis of Xenia diterpenoids and related metabolites isolated from marine organisms

• Tatjana Huber,
• Lara Weisheit and
• Thomas Magauer

Beilstein J. Org. Chem. 2015, 11, 2521–2539, doi:10.3762/bjoc.11.273

• Tatjana Huber Lara Weisheit Thomas Magauer Department of Chemistry and Pharmacy, Ludwig-Maximilians-University Munich, Butenandtstraße 5–13, 81377 Munich, Germany 10.3762/bjoc.11.273 Abstract This review describes strategies for the chemical synthesis of xenicane diterpenoids and structurally

Two strategies for the synthesis of the biologically important ATP analogue ApppI, at a multi-milligram scale

• Janne Weisell,
• Jouko Vepsäläinen and
• Petri A. Turhanen

Beilstein J. Org. Chem. 2015, 11, 2189–2193, doi:10.3762/bjoc.11.237

• the chemical synthesis of ApppI. One is the method Mönkkönen et al. [3] followed in their synthesis which has been first described by Eggerer and Lynen [5] and another method is the chemical synthesis of ApppI described by Vantourout et al. [6]. According to our earlier experiments following the

Design and synthesis of propellane derivatives and oxa-bowls via ring-rearrangement metathesis as a key step

• Sambasivarao Kotha and
• Rama Gunta

Beilstein J. Org. Chem. 2015, 11, 1727–1731, doi:10.3762/bjoc.11.188

• target molecule, eventually to arrive at simple starting materials by working in an opposite direction to a chemical synthesis. The ‘retrosynthetic analysis’ was first introduced by E. J. Corey and defined as “it is a problem solving technique for transforming the structure of a synthetic target molecule

• to a sequence of progressively simpler structures along a pathway which ultimately leads to a simple or commercially available starting materials for a chemical synthesis” [1] . Generally, this type of retrosynthetic analysis has been used to design [2][3][4][5][6] the target molecule. However, a

The synthesis of active pharmaceutical ingredients (APIs) using continuous flow chemistry

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2015, 11, 1194–1219, doi:10.3762/bjoc.11.134

• incorporated analysis technique. As the safe use of organometallic reagents has emerged as a key facet of flow chemical synthesis [58], the ITC reported on the design and implementation of a dual injection loop system that could deliver solutions of organometallic reagents (i.e., LiHMDS or n-BuLi) as a pseudo

• chemistry is an increase in reproducibility this seems a rather negative trend. In 2012 researchers from AstraZeneca (Sweden) reported upon a scale-up campaign for their gastroesophageal reflux inhibitor programme. Specifically, flow chemical synthesis was used to efficiently and reliably provide sufficient

• in flow Another example in which flow chemical synthesis was used as the key step in an industrial setting was reported by scientists from Eli Lilly (USA) in 2012. An asymmetric high-pressure hydrogenation towards LY500307 (82) [75] was demonstrated (Scheme 14). As this campaign aimed to produce the

Azobenzene-based inhibitors of human carbonic anhydrase II

• Leander Simon Runtsch,
• David Michael Barber,
• Peter Mayer,
• Michael Groll,
• Dirk Trauner and
• Johannes Broichhagen

Beilstein J. Org. Chem. 2015, 11, 1129–1135, doi:10.3762/bjoc.11.127

• of the synthesized azobenzenes, we found that the electronic structure does not strongly affect inhibition. Taken together, all compounds are strong blockers of hCAII with Ki = 25–65 nM that are potentially photochromic and thus combine studies from chemical synthesis, crystallography and enzyme

Synthesis of photoresponsive cholesterol-based azobenzene organogels: dependence on different spacer lengths

• Yuchun Ren,
• Bin Wang and
• Xiuqing Zhang

Beilstein J. Org. Chem. 2015, 11, 1089–1095, doi:10.3762/bjoc.11.122

• Yuchun Ren Bin Wang Xiuqing Zhang Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province of China, China West Normal University, Nanchong 637009, China 10.3762/bjoc.11.122 Abstract A series of azobenzene–cholesterol organogel compounds (M0–M12) with different spacers were

• of China (2010008), Key Project of Natural Science of Sichuan Educational Department of China (12ZA175), Chemical synthesis and Pollution Control Key Laboratory of Sichuan Province of China (CSCP2013-2), and University research and launch projects of China West Normal University in 2014 (14C003).

N-Alkyl derivatives of diosgenyl 2-amino-2-deoxy-β-D-glucopyranoside; synthesis and antimicrobial activity

• Agata Walczewska,
• Daria Grzywacz,
• Dorota Bednarczyk,
• Małgorzata Dawgul,
• Andrzej Nowacki,
• Wojciech Kamysz,
• Beata Liberek and
• Henryk Myszka

Beilstein J. Org. Chem. 2015, 11, 869–874, doi:10.3762/bjoc.11.97

• fact that thousands of homogeneous saponins have been characterized, new types of saponins are regularly isolated from nature and their biological activities are evaluated [7][8][9][10][11]. The yields of homogenous saponins isolated from natural sources are rather low. Therefore, chemical synthesis of

CO₂ Chemistry

• Thomas E. Müller and
• Walter Leitner

Beilstein J. Org. Chem. 2015, 11, 675–677, doi:10.3762/bjoc.11.76

• use of carbon dioxide as chemical feedstock. Notably, the use of CO2 for manufacturing materials and chemicals is still in its infancy. Carbon dioxide (CO2) has long stirred the fascination of chemists. A rich chemistry has evolved utilizing this molecule in chemical synthesis [4]. Hitherto the low

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

• chemical synthesis. In principle, they can function as inexpensive, chiral and densely functionalized starting materials. On the other hand, the use of amino acid starting materials routinely necessitates protective group chemistry, and in reality, large-scale preparations of even the simplest side-chain

Synthesis and biological evaluation of a novel MUC1 glycopeptide conjugate vaccine candidate comprising a 4’-deoxy-4’-fluoro-Thomsen–Friedenreich epitope

• Manuel Johannes,
• Maximilian Reindl,
• Bastian Gerlitzki,
• Edgar Schmitt and
• Anja Hoffmann-Röder

Beilstein J. Org. Chem. 2015, 11, 155–161, doi:10.3762/bjoc.11.15

• epitopes. Use of tetanus toxoid (TTox) and bovine serum albumin (BSA) as immunogenic carrier proteins allows application of these conjugates in immunization studies and diagnostic ELISA experiments [44]. Results and Discussion Chemical synthesis of the 4’-fluoro-TF neo-glycoconjugate The synthesis of the 4

NAA-modified DNA oligonucleotides with zwitterionic backbones: stereoselective synthesis of A–T phosphoramidite building blocks

• Boris Schmidtgall,
• Claudia Höbartner and
• Christian Ducho

Beilstein J. Org. Chem. 2015, 11, 50–60, doi:10.3762/bjoc.11.8

• represents the first step towards a comprehensive set of 'dimeric' NAA-linked X–T phosphoramidites for the automated chemical synthesis of NAA-modified DNA oligonucleotides. Results and Discussion For the synthesis of target phosphoramidites 7, it was planned to employ a similar synthetic strategy as

Nucleic acid chemistry

• Hans-Achim Wagenknecht

Beilstein J. Org. Chem. 2014, 10, 2928–2929, doi:10.3762/bjoc.10.311

• is of critical importance, carrying the genetic information for all living organisms. Only a few years later appeared the first reports on the chemical synthesis of oligonucleotides with a natural 3'-5' phosphodiester linker by Michelsen and Todd [2]. It took another two decades until the first step

Encapsulation of biocides by cyclodextrins: toward synergistic effects against pathogens

• Véronique Nardello-Rataj and
• Loïc Leclercq

Beilstein J. Org. Chem. 2014, 10, 2603–2622, doi:10.3762/bjoc.10.273

• ), and v) they are biodegradable and do not pollute the environment. Their main fields of application are: agriculture, food industry, biotechnology, pharmaceutical industry, chemical and biological analysis, chemical synthesis, catalysis, materials, cosmetic industry, environmental protection

A versatile δ-aminolevulinic acid (ΑLA)-cyclodextrin bimodal conjugate-prodrug for PDT applications with the help of intracellular chemistry

• Chrysie Aggelidou,
• Theodossis A. Theodossiou,
• Antonio Ricardo Gonçalves,
• Mariza Lampropoulou and
• Konstantina Yannakopoulou

Beilstein J. Org. Chem. 2014, 10, 2414–2420, doi:10.3762/bjoc.10.251

• prodrug 2, bearing ~3 δ-aminolevulinic acid moieties per β-CD macrocycle. The dual nature of the system was exemplified by the intracellular formation of PpIX using “intracellular chemical synthesis”. At the same time 2 was able to carry inside the cytoplasm a model guest molecule. The possibility that

Synthesis and immunological evaluation of protein conjugates of Neisseria meningitidis X capsular polysaccharide fragments

• Laura Morelli,
• Damiano Cancogni,
• Marta Tontini,
• Alberto Nilo,
• Sara Filippini,
• Paolo Costantino,
• Maria Rosaria Romano,
• Francesco Berti,
• Roberto Adamo and
• Luigi Lay

Beilstein J. Org. Chem. 2014, 10, 2367–2376, doi:10.3762/bjoc.10.247

• units might be required to fully mimic the polysaccharide activity, and paves the ground for a deeper understanding of the structural requirements needed to develop a conjugate vaccine based on well-defined oligosaccharides attained by chemical synthesis. The preparation of these longer chain MenX

• of the hemiacetal under these reaction conditions. Compound 9 was subjected to Zemplén transesterification with NaOMe in methanol to afford alcohol 10, and the hydrogenolytic removal of the remaining protective groups furnished the spacer-linked monomer 1 in excellent yield (Scheme 2). Chemical

• synthesis of neo-glycoconjugates Fragments 1–3, obtained as previously reported [25], were employed as follows for the synthesis of the corresponding CRM197 conjugates. First the oligomers 1–3 were activated by reaction with an excess of SIDEA in the presence of triethylamine in DMSO (Scheme 3). The

Specific DNA duplex formation at an artificial lipid bilayer: fluorescence microscopy after Sybr Green I staining

• Emma Werz and
• Helmut Rosemeyer

Beilstein J. Org. Chem. 2014, 10, 2307–2321, doi:10.3762/bjoc.10.240

• ][22]. This bears the advantage that the target DNA – the presence or absence of which is going to be analysed – should not be labelled separately with a fluorochrome tag such as cyanine-5 (Cy5) or TAMRA, neither by chemical synthesis nor by a polymerase chain reaction (PCR). The chemical formulae (1–3

Reversibly locked thionucleobase pairs in DNA to study base flipping enzymes

• Christine Beuck and
• Elmar Weinhold

Beilstein J. Org. Chem. 2014, 10, 2293–2306, doi:10.3762/bjoc.10.239

• nucleotides mimicking these alkylation products have been synthesized and then converted into the phosphoamidite building block for chemical DNA synthesis [6][7][18][19][20][21][22][23][24][25][26][27][28]. Not only do these protocols require extensive chemical synthesis, but the sequence of the synthesized

• , without the need of extensive chemical synthesis and with no restrictions with respect to the DNA sequence. The cross-linked analogs of both an A/T and a G/C base pair can be obtained by starting with either an I6S/U4S or G6S/U4S base pair, and therefore, this chemistry can be employed to study any DNA

The chemoenzymatic synthesis of clofarabine and related 2′-deoxyfluoroarabinosyl nucleosides: the electronic and stereochemical factors determining substrate recognition by E. coli nucleoside phosphorylases

• Ilja V. Fateev,
• Konstantin V. Antonov,
• Irina D. Konstantinova,
• Tatyana I. Muravyova,
• Frank Seela,
• Roman S. Esipov,
• Anatoly I. Miroshnikov and
• Igor A. Mikhailopulo

Beilstein J. Org. Chem. 2014, 10, 1657–1669, doi:10.3762/bjoc.10.173

• synthesis of 2-chloro-9-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)adenine (1, clofarabine) were studied. The first approach consists in the chemical synthesis of 2-deoxy-2-fluoro-α-D-arabinofuranose-1-phosphate (12a, 2FAra-1P) via three step conversion of 1,3,5-tri-O-benzoyl-2-deoxy-2-fluoro-α-D

• formation of the α/β mixtures of N-9 and N-7 glycosides (cf. [17]). Despite the detailed analysis and optimization of the clofarabine process [12][13] and the bulk production of the protected nucleoside glycon 9 by chemists at Eli Lilly and Co. [18] this chemical synthesis is connected with the use of great

• conclusion that the search for novel more efficient “green” methods is of reasonable interest. In this context, the study by Yamada et al. on the chemical synthesis of 2-deoxy-2-fluoro-α-D-arabinofuranose-1-phosphate (12a; 2FAra-1P) and its use in an enzymatic coupling with purine bases is of great interest