Total syntheses of the archazolids: an emerging class of novel anticancer drugs

• Stephan Scheeff and
• Dirk Menche

Beilstein J. Org. Chem. 2017, 13, 1085–1098, doi:10.3762/bjoc.13.108

• inhibition of V-ATPase abrogates tumor metastasis via repression of endocytic activation [28], leads to impaired cathepsin B activation in vivo [30], modulates anoikis resistance and metastasis of cancer cells [31], overcomes trastuzumab resistance of breast cancers [32], blocks iron metabolism and thereby

α-Acetoxyarone synthesis via iodine-catalyzed and tert-butyl hydroperoxide-mediateded self-intermolecular oxidative coupling of aryl ketones

• Liquan Tan,
• Cui Chen and
• Weibing Liu

Beilstein J. Org. Chem. 2017, 13, 1079–1084, doi:10.3762/bjoc.13.107

• was limited to α-substituted aryl ketones, and acetophenones were unsuitable for this conversion. In addition, this method requires harsh catalytic conditions, using scarce iron and copper complexes. The development of novel metal-free methods for the preparation of α-acetoxyaryl ketones is therefore

Molecular-level architectural design using benzothiadiazole-based polymers for photovoltaic applications

• Vinila N. Viswanathan,
• Arun D. Rao,
• Upendra K. Pandey,
• Arul Varman Kesavan and
• Praveen C. Ramamurthy

Beilstein J. Org. Chem. 2017, 13, 863–873, doi:10.3762/bjoc.13.87

• nitric acid and acetic acid gave dinitro compound 6. The nitro groups in 6 were then reduced by treatment with iron powder and acetic acid. The cyclization of the diamino compound 7 (as described for compound 1) afforded the difluorinated benzothiadiazole 8. The monomer M2 was obtained by coupling 8 with

Conjecture and hypothesis: The importance of reality checks

• David Deamer

Beilstein J. Org. Chem. 2017, 13, 620–624, doi:10.3762/bjoc.13.60

• universal common ancestor (LUCA) may have originated in hydrothermal vents. The iron-sulfur chemistry proposed for hydrothermal vents was tested by Huber and Wächtershäuser [15][16] who simulated vent conditions with boiling mixtures of iron and nickel sulfides to which various reactants were added. They

Transition-metal-catalyzed synthesis of phenols and aryl thiols

• Yajun Liu,
• Shasha Liu and
• Yan Xiao

Beilstein J. Org. Chem. 2017, 13, 589–611, doi:10.3762/bjoc.13.58

• Pd(OAc)2 as catalyst and molecular oxygen as oxidant, however, the reaction suffered from low yield (2.3%) [49][50]. In 1997, Seo and co-workers reported an iron-HPA (heteropoly acid)-complex-catalyzed protocol for oxidation of benzene to phenol [51]. In 2005, the Rybak-Akimova group reported that

• they used a stoichiometric amount of reactive iron complex [Fe(II)(BPMEN)(CH3CN)2](ClO4)2 to achieve ortho-hydroxylation of benzoic acid in the presence of H2O2, affording salicylic acid in low yields [52]. In the past decade, the selectivity and yield of C–H hydroxylation of arenes were highly

Effect of the ortho-hydroxy group of salicylaldehyde in the A³ coupling reaction: A metal-catalyst-free synthesis of propargylamine

• Sujit Ghosh,
• Kinkar Biswas,
• Suchandra Bhattacharya,
• Pranab Ghosh and
• Basudeb Basu

Beilstein J. Org. Chem. 2017, 13, 552–557, doi:10.3762/bjoc.13.53

• known as A3 coupling reaction, remains the most common and straightforward method for the synthesis of propargylamine. The A3 coupling reaction is reported under transition-metal-catalyzed conditions using copper [12][17][18][19], gold [17][20][21], silver [17][22], zinc [17][23], nickel [24], iron [25

Synthesis of 1-indanones with a broad range of biological activity

• Marika Turek,
• Dorota Szczęsna,
• Marek Koprowski and
• Piotr Bałczewski

Beilstein J. Org. Chem. 2017, 13, 451–494, doi:10.3762/bjoc.13.48

• obtained from the reaction of o-phthalaldehyde (86) with acetophenone 87 (Scheme 28). Iron(III) complexes of 88a–d turned out to be promising candidates for potential photovoltaic or luminescence applications. An intramolecular hydroacylation, catalyzed by nickel(0)/N-heterocyclic carbenes leading to the

Adsorption of RNA on mineral surfaces and mineral precipitates

• Elisa Biondi,
• Yoshihiro Furukawa,
• Jun Kawai and
• Steven A. Benner

Beilstein J. Org. Chem. 2017, 13, 393–404, doi:10.3762/bjoc.13.42

• particularly sensible using this approach. For example, iron phosphate is a well-known mineral (vivianite) and it adsorbs RNA (≈12%, Table 2). However, it does not make sense to seek the Periodic Table correlates of vivianite below iron. This would require us making and/or finding ruthenium phosphate and

• osmium phosphate, neither of which has been reported in mineralogy. Likewise, horizontal comparisons across the Periodic Table are problematic, even within transition metals. For example, we found that RNA binds to natural titanium dioxide (rutile, 21% in our experiments) and iron(III) oxide (Fe2O3

• the RNA. The green color is often attributed to small amounts of iron or samarium within the mineral lattice. This difference, although observed on only two different specimens from two different sources, is cautionary. Materials and Methods Radiolabeled RNA For this study, a 83-nt long labeled RNA

The reductive decyanation reaction: an overview and recent developments

• Jean-Marc R. Mattalia

Beilstein J. Org. Chem. 2017, 13, 267–284, doi:10.3762/bjoc.13.30

• ]. Iron-catalyzed reductive decyanation In 1982, Yamamoto et al. disclosed the C–CN bond cleavage promoted by an electron-rich cobalt complex [92]. Since that time, the activation of inert C–CN bonds by transition metals has been widely investigated. Improvements towards mild and green conditions with a

• bond cleavage catalyzed by iron complexes of a few primary alkyl cyanides and aryl cyanides in the presence of Et3SiH [100][101]. Decyanated species were formed together with silyl cyanide. Both aliphatic and aromatic nitriles were successfully reduced (Scheme 16) but an electron-withdrawing, bulky or

Stabilization of nanosized titanium dioxide by cyclodextrin polymers and its photocatalytic effect on the degradation of wastewater pollutants

• Tamás Zoltán Agócs,
• István Puskás,
• Erzsébet Varga,
• Mónika Molnár and
• Éva Fenyvesi

Beilstein J. Org. Chem. 2016, 12, 2873–2882, doi:10.3762/bjoc.12.286

• presence of CMBCD-P only. The results for MB are summarized in Figure 5 and Table 3. Interestingly, without catalyst MB was decomposed faster in tap water than in distilled water most probably due to the small concentration of iron present. Fe(III) and organic carboxylic acid, which coexist in natural

Biochemical and structural characterisation of the second oxidative crosslinking step during the biosynthesis of the glycopeptide antibiotic A47934

• Veronika Ulrich,
• Clara Brieke and
• Max J. Cryle

Beilstein J. Org. Chem. 2016, 12, 2849–2864, doi:10.3762/bjoc.12.284

• , although in this case there is direct coordination between the N-terminal amine nitrogen and the heme iron. This different binding mode leads to minor changes in the orientation of various amino acid side chains within the active site of OxyAtei when compared to StaF as well as the opening of the F-G

Continuous-flow synthesis of primary amines: Metal-free reduction of aliphatic and aromatic nitro derivatives with trichlorosilane

• Riccardo Porta,
• Alessandra Puglisi,
• Giacomo Colombo,
• Sergio Rossi and
• Maurizio Benaglia

Beilstein J. Org. Chem. 2016, 12, 2614–2619, doi:10.3762/bjoc.12.257

• reducing agent and iron oxide nanocrystals as the catalyst [25]. This methodology ensured fast transformations (2 to 8 minutes) of a wide number of substrates and was extended to large scale preparation of pharmaceutically relevant anilines [26]. However, this procedure required harsh reaction conditions

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

• formation of the required ylide intermediate, a base is not necessary, but the authors reported that when it was omitted from a control reaction, no reaction occurred. Finally, Bernd Plietker and co-workers have very recently reported the use of iron complex 38 as a catalyst for phosphine oxide reduction

Robust C–C bonded porous networks with chemically designed functionalities for improved CO₂ capture from flue gas

• Damien Thirion,
• Joo S. Lee,
• Ercan Özdemir and
• Cafer T. Yavuz

Beilstein J. Org. Chem. 2016, 12, 2274–2279, doi:10.3762/bjoc.12.220

• ]. HCPs are mainly synthesized through Friedel–Crafts alkylation using iron chloride and thus, are not relying on precious metals. Unfortunately, Friedel–Crafts reactions are not very tolerant to functional groups like nitriles or amines [7]. On the other hand, structures incorporating heteroatoms, such

Thiophene-forming one-pot synthesis of three thienyl-bridged oligophenothiazines and their electronic properties

• Dominik Urselmann,
• Konstantin Deilhof,
• Bernhard Mayer and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2016, 12, 2055–2064, doi:10.3762/bjoc.12.194

• to form self-assembled monolayers on gold [69][70][71] as well as on zinc and iron oxide surfaces [72]. Conceptually, thienyl-bridged oligophenothiazines can be considered as a novel type of structurally well-defined electron-rich oligophenothiazine–thiophene hybrids (Figure 1). Thereby, the strong

Economical and scalable synthesis of 6-amino-2-cyanobenzothiazole

• Jacob R. Hauser,
• Hester A. Beard,
• Mary E. Bayana,
• Katherine E. Jolley,
• Stuart L. Warriner and
• Robin S. Bon

Beilstein J. Org. Chem. 2016, 12, 2019–2025, doi:10.3762/bjoc.12.189

• , resulted in full conversion to 2-cyano-6-nitrobenzothiazole (13, Table 1), a known precursor of ACBT 8 [7]. Any unreacted cyanide in the reaction mixture was safely quenched by the addition of an iron(III) chloride solution, and pure ACBT 8 was isolated in 90% yield after (extensive) extractive work-up and

• full conversion to 13, and pure 13 which was isolated in 75% yield after quenching with iron(III) chloride solution, extraction and simple filtration through a silica plug (Table 1, entry 3). The straightforward work-up/purification procedure – in the absence of DMSO as a co-solvent – outweighed the

• to prevent potential thermal runaway upon scale-up. The DABCO-catalysed cyanation reaction was scaled up in two steps: using 2 g and then 10 g of substrate 6 (Scheme 3). After quenching with iron(III) chloride solution, extractive work-up and filtration through a short silica plug, product 13 was

Stereo- and regioselectivity of the hetero-Diels–Alder reaction of nitroso derivatives with conjugated dienes

• Lucie Brulíková,
• Aidan Harrison,
• Marvin J. Miller and
• Jan Hlaváč

Beilstein J. Org. Chem. 2016, 12, 1949–1980, doi:10.3762/bjoc.12.184

• an arylnitroso dienophile and an iron-bound substituted 1,3-cyclohexadiene 103, changing the aryl ring (Ar’) from pyridine to phenyl increased the regioselectivity from 2:1 (105/104) to complete regioselectivity for the reverse isomer 104 (Table 2) [101]. The results for the regiocontrol for aryl

Cross-linked cyclodextrin-based material for treatment of metals and organic substances present in industrial discharge waters

• Élise Euvrard,
• Nadia Morin-Crini,
• Coline Druart,
• Justine Bugnet,
• Bernard Martel,
• Cesare Cosentino,
• Virginie Moutarlier and
• Grégorio Crini

Beilstein J. Org. Chem. 2016, 12, 1826–1838, doi:10.3762/bjoc.12.172

• cationic dyes. Zhang et al. [4] studied the removal of cobalt and 1-naphthol onto magnetic nanoparticles containing cyclodextrin and iron and Yang et al. [5] proposed a new nanocomposite adsorbent for the simultaneous removal of organic and inorganic substances from water. Here, we propose to use a single

Amidofluorene-appended lower rim 1,3-diconjugate of calix[4]arene: synthesis, characterization and highly selective sensor for Cu²⁺

• Rahman Hosseinzadeh,
• Mohammad Nemati,
• Reza Zadmard and
• Maryam Mohadjerani

Beilstein J. Org. Chem. 2016, 12, 1749–1757, doi:10.3762/bjoc.12.163

• –7.87 (m, 2H), 7.64 (d, J = 6.4 Hz, 1H), 7.49–7.43 (m, 2H), 4.02 (s, 2H) ppm; 13C NMR (CDCl3, 100 MHz) δ 148.09, 146.79, 144.81, 143.92, 139.47, 128.87, 127.43, 125.43, 123.14, 121.34, 120.49, 119.88, 36.96 ppm. 9H-Fluoren-2-amine (4) [40]: A mixture of 2-nitro-9H-fluorene (2.0 g, 9.5 mmol), iron powder

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

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

Towards potential nanoparticle contrast agents: Synthesis of new functionalized PEG bisphosphonates

• Souad Kachbi-Khelfallah,
• Maelle Monteil,
• Margery Cortes-Clerget,
• Evelyne Migianu-Griffoni,
• Jean-Luc Pirat,
• Olivier Gager,
• Julia Deschamp and
• Marc Lecouvey

Beilstein J. Org. Chem. 2016, 12, 1366–1371, doi:10.3762/bjoc.12.130

• the development of superparamagnetic iron oxide nanoparticles (SPIONPs) because of their biocompatibility which allows there in vivo use both for diagnosis in magnetic resonance imaging and in therapy [1][2]. Most often, it is necessary to modify the surface of SPIONPs to increase the metabolic

• obtain the expected HMBP-PEG-COOH 23 in 85% yield. Conclusion In summary, novel bifunctional PEG-HMBPs ligands for the coating of iron oxide nanoparticles have been synthesized. The procedure is efficient to introduce different functional groups such as azide, carboxylic acid, amine permitting further

On the mechanism of imine elimination from Fischer tungsten carbene complexes

• Philipp Veit,
• Christoph Förster and
• Katja Heinze

Beilstein J. Org. Chem. 2016, 12, 1322–1333, doi:10.3762/bjoc.12.125

• addition has been proposed in the literature for the iron (aminophenyl)phenylcarbene complex [Cp(CO)(S(SiEt3))Fe(4)] leading to an intermediate hydrido species followed by the elimination of E-1,2-diphenylimine E-5 [73]. Pseudorotation of cis(N,H)-W(CO)4(H)(Z-15) to the isoenergetic rotamer cis(C,H)-W(CO)4

Cyclisation mechanisms in the biosynthesis of ribosomally synthesised and post-translationally modified peptides

• Andrew W. Truman

Beilstein J. Org. Chem. 2016, 12, 1250–1268, doi:10.3762/bjoc.12.120

• the highly reactive iron–sulphur clusters in these proteins make them capable of carrying out complex oxidative chemistry. This protein family has been named after currently characterised pathways (SPASM = subtilosin, PQQ, anaerobic sulfatase, and mycofactocin), although the mycofactocin pathway has

Synthesis of β-arylated alkylamides via Pd-catalyzed one-pot installation of a directing group and C(sp³)–H arylation

• Yunyun Liu,
• Yi Zhang,
• Xiaoji Cao and
• Jie-Ping Wan

Beilstein J. Org. Chem. 2016, 12, 1122–1126, doi:10.3762/bjoc.12.108

• employing different transition metal catalysts such as palladium, nickel, and iron have provided enriched routes for the synthesis of structurally diverse amides, a two step process involving the operation in installing the AQ to the substrate has been required [41][42][43][44][45][46][47][48][49][50