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Exploration of scope of an optimized one-pot sequential procedure for preparing of 2,4-di- and 2,4,5-tri-substituted thiazoles has been accomplished. The synthesis was performed by the initial formation of a β-keto-thioester intermediate from nucleophilic substitution of α-bromoketones with thioacid potassium salts, followed by treatment with ammonium acetate and one equivalent of acetic acid in toluene to form imine intermediate eventually leading to cyclization yielding thiazoles. This procedure should be highlighted with a flexible way to control the substitution pattern around thiazole ring by choosing appropriately substituted α-bromoketones even containing acid labile functionality and thioacid potassium salts, and thus its applicability is very wide.

The total synthesis of (−)-conduramine A-1 was achieved by using a diastereomerically enriched syn , anti -oxazine intermediate. The key steps in this strategy were the stereoselective extension of the chirality of syn , anti -oxazine, a Wittig reaction, and a ring-closing metathesis reaction.

The rhodium(III)-catalyzed direct cross-coupling reaction of electron-deficient acrylamides with maleimides is described. This protocol displays broad functional group tolerance and high efficiency, which offers a new opportunity to access highly substituted succinimides. Dependent on the substituent positions of acrylamides and reaction conditions, olefin migrated products were obtained with high regio- and stereoselectivity.

Aryl- and alkyl substituted enals react according to the regioselective title reaction to form a mixture of three diastereomeric cyclopropanation products in high yields and with often very high enantioselectivities.

A Cu-catalyzed highly Z-stereoselective hydroboration of alkynes with 1,8-naphthalenediaminatoborane (HB(dan)) is developed. DPEphos (bis[(2-diphenylphosphino)phenyl]ether)-ligated Cu catalysts produced alkenylboron compounds from terminal alkynes with excellent Z-stereoselectivity. In contrast, using a SIPr–CuCl complex as the precatalyst exclusively produced E-hydroboration products at mild conditions. Both catalytic procedures form alkenylboron products stereocomplementary to each other, constituting stereodivergent hydroboration of alkynes through Cu catalysis. Deuterium labeling and isomerization studies support the Z-selective hydroboration via trans-addition of the boron reagent to terminal alkynes as opposed to precedent noble-metal-catalyzed trans-hydroborations.

Enantiodivergent catalyst systems were developed using metals with different ionic radii and a multifunctional brucine diol (BD) ligand. The catalytic use of purported 1:1 Cu-BD complexes in the 1,3-dipolar cycloaddition of azomethine ylides with chalcones resulted in the selective formation of endo-pyrrolidines in 87–96% ees with an absolute stereochemical outcome of (2R,3S,4R,5S). In contrast, an opposite absolute stereochemical outcome was observed by using the catalysts derived from Ag(I) salts and BD. The demonstration of enantiodivergent approaches to a broad class of substrates/reaction types underlines their synthetic value in asymmetric synthesis.

A transition metal-free, chemoselective reaction was performed using the sodium tert-butoxide-oxygen (NaO(t) Bu-O2 ) system, resulting in either oxidative dehomologation or direct oxidation of alcohols. In particular, the newly developed protocol may be used to predict the major product formed, which depends on alkyl chain length of the alcohols and reaction conditions. The rational mechanism of this transformation was also demonstrated by performing an (18) O isotopic labelling experiment. This protocol presents a straightforward method for biomass conversion of a lignin model compound to phenol and benzoic acid.

Review: focus on metallic Li anodes, but Mg, Na, Al, and Zn electrodes are included; 286 refs.

A method for copper(II)-mediated N–N bond formation of N-imidoylisothioureas has been developed for the synthesis of 1,2,4-triazoles. The reaction requires cerium(IV) sulfate as an oxidant and proceeds at room temperature. This approach provides access to a variety of substituted 1,2,4-triazoles.

The use of the Broensted base, Et3N, along with a catalytic amount of Lewis base, PPh3, leads to the isomerization of chlorovinyl ketones affording 1,3-dienones.

The revelation of the anticancer properties of cisplatin has inspired research into metal complexes for the treatment of cancer. Several second and third generation cisplatin analogues were developed with claims of good anticancer properties and reduced side effects. However, the persistence of some side effects and the resistance of cancer cells have tempted scientists to explore new metal complexes as anticancer drugs. Therefore, the approach of rational drug design has been extended to the development of non-platinum anticancer drugs, and a large number of such complexes have been developed. Iron complexes are of interest to inorganic medicinal chemists for the development of anticancer agents. The anticancer potency of iron complexes was first reported in ferrocenium picrate and ferrocenium trichloroacetate salts, and was attributed to their ability to form reactive oxygen species, leading to oxidative DNA damage. This review discusses the advances in iron complexes as anticancer agents. The aspects of the photocytotoxicity, redox activity and multinuclearity of anticancer iron complexes are discussed, in addition to discussing ferrocenyl derivatives and salen complexes. The legacy of nanotechnology and synergism in harnessing the potential of iron complexes is highlighted. Finally, the current challenges and future perspectives of iron complexes as anticancer agents are outlined.

Microwave (MW) irradiation facilitated synthesis provides fast, safe, simple, and green reaction conditions. MW irradiation of 2-aminobenzophenones with heteroaromatic ketones afforded quinolines via Friedlander condensation in high yields with intact halogen substituents for further modifications. Dibenzo[b,f][1,5]diazocines were found as minor products and in some instances as the only products as the result of self-condensation of 2-aminobenzophenones. Different acid catalysts were found to affect these cyclization processes. Mini library of quinolines and dibenzo[b,f][1,5]diazocines were created in order to understand the substituents effect on the reaction. Resultant quinolines and dibenzo[b,f][1,5]diazocines are anticipated to serve as an interesting library for high throughput screening of various biological applications.

Chromanone-2-carboxylates and chroman-2-carboxylates are useful building blocks for the synthesis of a variety of bioactive compounds, such as repinotan, fidarestat, and nebivolol. An efficient and practical enantiospecific synthesis of chromanone-2-carboxylates and chroman-2-carboxylates has been accomplished using intramolecular Mitsunobu etherification of methyl ( S )-2-hydroxy-4-oxo-4-(2′-hydroxy)phenylbutanoates derived from l -malic acid.

This account summarizes the recent efforts in the Oh group toward the development of stereodivergent asymmetric catalysis using a single chiral source, namely brucine diol. Enantiodivergent catalytic approaches are discussed in the context of [3+2]-cycloaddition reactions, aldol-type reactions, and Friedel–Crafts alkylation reactions. Expansion of the brucine diol catalyzed asymmetric reactions is also detailed in diastereodivergent conjugate addition reactions as well as in a cooperative catalysis approach to the aldol reactions of methyl isocyanate. Collectively, the research presented in this account demonstrates the important mechanistic as well as practical significance of single ­chiral-source-based asymmetric catalysis. 1 Introduction 2 Enantiodivergent Approaches 2.1 [3+2]-Cycloaddition Reactions 2.2 Nitro-Aldol Reactions 2.3 Friedel–Crafts Alkylation Reactions 3 Diastereodivergent Approaches 3.1 Conjugate Addition Reactions 3.2 endo-Selective [3+2]-Cycloaddition Reactions 4 Cooperative Catalysis Approaches 5 Outlook

Malaria has been teasing human populations from a long time. Presently, several classes of antimalarial drugs are available in market, but the issues of toxicity, lower efficacy and the resistance by malarial parasites have decreased their overall therapeutic indices. Thus, the search for new promising antimalarials continues, however, the battle against malaria is far from over. Ferroquine is a derivative of chloroquine with antimalarial properties. It is the most successful of the chloroquine derivatives. Not only ferroquine, but also its derivatives have shown promising potential as antimalarials of clinical interest. Presently, much research is dedicated to the development of ferroquine derivatives as safe alternatives to antimalarial chemotherapy. The present article describes the structural, chemical and biological features of ferroquine. Several classes of ferroquine derivatives including hydroxyferroquines, trioxaferroquines, chloroquine-bridged ferrocenophanes, thiosemicarbazone derivatives, ferrocene dual conjugates, 4-N-substituted derivatives, and others have been discussed. Besides, the mechanism of action of ferroquine has been discussed. A careful observation has been made into pharmacologically significant ferroquine derivatives with better or equal therapeutic effects to that of chloroquine and ferroquine. A brief discussion of the toxicities of ferroquine derivatives has been made. Finally, efforts have been made to discuss the current challenges and future perspectives of ferroquine-based antimalarial drug development.

Described is a copper-catalyzed cascade reaction method for the conversion of 3,4-dihydropyrimidine-2(1 H )-thiones to arylthiopyrimidines, likely proceeded via C–S cross-coupling and oxidative dehydrogenation under aerobic conditions. The reaction method proceeded efficiently with a wide range of the dihydropyrimidinethione substrates and aryl iodides as coupling partners.

Single crystals of (IIIa—e) and (V) are hydrothermally grown and characterized by single crystal XRD, IR and UV/VIS spectroscopy, SEM, second harmonic generation measurements, and piezoelectric and polarization measurements.

YNbTe2O8 (I) and YNbSe2O8 (II) are prepared by solid state reaction of Y2O3, Nb2O5, and TeO2 or SeO2 (evacuated silica tubes, 900 °C, 2 d; cooling to 600 °C with a rate of 6 °C/h).

Racetrack memory stores digital data in the magnetic domain walls of nanowires. This technology promises to yield information storage devices with high reliability, performance and capacity.

The transformation of phenyl acetyl chlorides and asymmetrically disubstituted alkynes results in the regioselective formation of β-chlorovinyl ketone intermediates offering access to 3,4-disubstituted-2-naphthols.

For the presented approach no further additives like oxidants, acids, or bases are required.

The title Chevrel phases with x up to x = 1.7 as cathode materials for rechargeable Mg batteries are synthesized by chemical intercalation from stoichiometric mixtures of Mo6S8 powder and Cu metal (80 °C, 36 h).

Zn0.88Mg0.1M0.02O (M: Al, Ga, In, Tl) films are grown on quartz by radio-frequency magnetron sputtering using ceramic targets prepared by cold isostatic pressing and sintering of the respective metal oxide powders (950 °C, 6 h).

GaSe with a layered crystal structure is synthesized from a mixture of GaCl3, SeCl4, N2H4, NH4OH, and EtOH (pH 11, 80 °C, 3 h).

The title compound is synthesized from L-tyrosine via Pd-catalyzed stereoselective oxazine formation and subsequent hydrogenation.

Pure polycrystalline bulk samples and single crystals of InNb(TeO4)2, are prepared by solid state reaction of In2O3, Nb2O5, and TeO2 in the molar ratio of 1:1:6 (evacuated quartz tube, 800 °C, 2 d; controlled cooling).

Boron-doped TiO2 is prepared from H3BO3 and Ti(O-iPr)4 dissolved in iPrOH/H2O (10:1) by ultrasonication (90 min) and heat treatment of the product at 450 °C for 5 h under air.

The compound is synthesized from a chiral 1,3-oxazine using Wittig reaction followed by a cyclization as key features over ten steps with an overall yield of 15.7%.

The synthesized compounds are screened for their in vitro antiproliferative activities against some human cancer cell lines.

Common intermediates to biogenic precursors of arteminolides are synthesized via a key silicon-tethered intramolecular [5 + 2]oxidopyrylium cycloaddition reaction.

Single crystals and polycrystalline YVSe2O8 (I) and YVTe2O8 (II) are prepared from stoichiometric amounts of Y2O3, V2O5, and SeO2 in both hydrothermal (autoclave, 230 °C, 4 d) and solid-state reactions (evacuated silica tube, 650 °C, 2 d).

Y2MoSe3O12 (I) and Y2MoTe3O12 (II) are prepared by solid state reactions of stoichiometric amounts of Y2O3, MoO3, and SeO2 or TeO2 (evacuated silica tubes, 700 resp.

Treatment of β-chlorovinyl ketones with NEt3 and LiClO4 or LiBr results in formation of electrophilic lithium cumulenolates which smoothly react with nucleophiles such as another cumulenolate or ketimines to afford vinyl allenones like (II) or pyrrolidines of type (IV)/(VII) in a stereoselective manner.

Functionality preferences of metathesis Ru carbenes to various alkenes and alkynes with electronic and steric diversity were determined by using time-dependent fluorescence quenching. The functionality preferences depend not only on the properties of multiple bonds but also on the ligands on Ru. There was a good correlation between functionality preference and the metathesis reaction outcome. The correlation between functionality preference and exo/endo product ratio offers a solution to resolve the mechanistic issue related with alkene- vs alkyne-initiated pathway in ring-closing enyne metathesis. The correlation indicates the preference is likely to dictate the reaction pathway and eventually the outcome of the reaction. The Ru catalyst favoring alkyne over alkene provides more endo product, indicating that the reaction mainly initiates at the alkyne. By changing the substitution pattern, the preference can be reversed to give an exclusive exo product.