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We present the first total synthesis of (±) benzomalvin E, featuring a quinazolino moiety with a 6–6–6–7-fused tetracyclic skeleton containing three nitrogen atoms. The key transformation involves Cu-catalyzed intramolecular C–N arylation of quinazolinone, leading to a sclerotigenin analogue that undergoes nucleophilic addition with benzaldehyde, enabling the synthesis of (±) benzomalvin E in six linear steps with a 33% overall yield. The (±) benzomalvin E’s structure was validated by 2-D NMR and single crystal XRD analysis and was further transformed into (E)-benzomalvin B.

Peptide nucleic acids (PNAs), besides hybridizing to complementary DNA and RNAs, bind and stabilize DNA secondary structures. Herein, we illustrate the design and synthesis of PNA-like scaffolds by incorporating five-membered thiazole rings as modified bases instead of nucleobases and their subsequent effects on gene regulation by biophysical and in vitroassays. A thiazole-modified PNA trimer selectively recognizes c-MYCG-quadruplex (G4) DNA over other G4s and duplex DNA. It displays a high stabilization potential for the c-MYCG4 DNA and shows remarkable fluorescence enhancement with the c-MYCG4. It is flexible enough to bind at 5′ and 3′ ends as well as in the groove region of c-MYCG4. Furthermore, the PNA trimer easily permeates the cellular membrane and suppresses c-MYCmRNA expression in HeLa cells by targeting the promoter G4. This study illuminates modified PNAs as flexible molecular tools for selective targeting of noncanonical nucleic acids and modulating gene function.

We herein report an efficient synthetic protocol to access heterocyclic dihydroquinazolinones by a transition-metal-free process, involving the reaction of 2-aminobenzonitriles with aldehydes in the presence of KOtBu. The method is compatible with aromatic ketones providing 2,2-disubstituted dihydroquinazolinones in high yields. This reaction proceeds feasibly at room temperature and features a broad substrate scope and tolerance to a range of functional groups. The mechanism follows a radical pathway.

We herein report the synthesis and biophysical evaluation of triazolyl dibenzo[a,c]phenazine derivatives as a novel class of G‐quadruplex ligands. The aromatic core facilitates π‐π interaction and the flexible, protonable side chains interact with the phosphate backbone of DNA viaelectrostatic interactions. Förster resonance energy transfer (FRET) melting assay and isothermal titration calorimetry (ITC) studies suggest that these ligands show binding preference for the hTELOG‐quadruplex over G‐quadruplexes found in the promoter region of various oncogenes and duplex DNA. The in vitrotelomeric repeat amplification protocol (Q‐TRAP) assay reveals that these ligands reduce telomerase activity in cancer cells. Bistriazolyl dibenzo[a,c]phenazine derivativesshow high stabilization potential and exothermic binding interaction with human telomeric (hTELO) quadruplex over other promoter G‐quadruplexes in biophysical studies. The in vitrotelomeric repeat amplification protocol (Q‐TRAP) assay reveal that they inhibit telomerase activity possibly through preferential interaction with the hTELOquadruplex.

The assembly of guanosine and boronic acids produces anionic hydrogels (G–B hydrogels) that mimic the topology of the DNA G-quadruplex. We herein demonstrate an unconventional approach of using the G–B hydrogel as a supramolecular template that assembles the irreversible formation of DNA G-quadruplex-selective 1,4-triazole ligands from a pool of alkyne–azide building blocks. These generated ligands could also stabilize and strengthen the gel assembly.

We herein report that hydrogels can be prepared from guanosine and boronic acids in the presence of K+and Pb2+ions. These supramolecular hydrogels are formed via G-quartet like self-assembly of guanosine and its boronate esters. The potential of this hydrogel construct in mimicking enzyme-like activity has been demonstrated for the first time. We have observed that the self-assembled structure present in K+stabilized hydrogel binds to iron(III)-hemin and shows peroxidase activity, catalyzing oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H2O2. Furthermore, the conformation of the G-quartet assemblies in the hydrogel can be altered by varying the stabilizing cations K+and Pb2+. This conformational switching has been used to devise a molecular logic gate for sensing of toxic Pb2+ions.

This study presents an efficient synthetic strategy for phenanthrenes and 1-hydroxyphenanthrenes through aromatization-assisted ring-closing metathesis (RCM). It involves vinylation of 1-bromo-2-naphthaldehyde derivatives, Barbier allylation, and subsequent one-pot RCM/dehydration of the diene precursors to yield phenanthrene derivatives. Further, the corresponding keto analogues of diene precursors produce 1-hydroxyphenanthrenes through RCM and aromatization-driven keto–enol tautomerism. This pathway enables rapid access to a diverse array of functionalized phenanthrenes and 1-hydroxyphenanthrenes, including synthetically challenging derivatives containing both –OH and –OMe groups via the sequential construction of the terminal phenanthrene ring.

This manuscript describes the development of a remarkably general palladium-catalyzed monoacylation of carbazoles using toluene derivatives playing the dual role of acyl source and organic solvent. The method uses NHPI as the cocatalyst and oxygen as the sole oxidant. Interestingly, the acylation of monosubstituted N-pyridylcarbazoles takes place regioselectively at the C-8 position. The scope of the method is explored using aldehyde as the acyl source. This highly site-selective acylation proceeds through a radical process.

Guanine-rich DNA sequences have the propensity to adopt four-stranded tetrahelical G-quadruplex (G4) structures that are overrepresented in gene promoters. The structural polymorphism and physicochemical properties of these non-Watson–Crick G4 structures make them important targets for drug development. The guanine-rich nuclease hypersensitivity element III1present in the upstream of P1 promoter of c-MYConcogene has the ability to form an intramolecular parallel G4 structure. The G4 structure that forms transiently in the c-MYCpromoter functions as a transcriptional repressor element. The c-MYConcogene is overexpressed in a wide variety of cancers and plays a key role in cancer progression. Till now, a large number of compounds that are capable of interacting and stabilizing thec-MYCG4 have been reported. In this review, we summarize various c-MYCG4 specific molecules and discuss their effects on c-MYCgene expression in vitroand in vivo.

Delivery of therapeutics to the intestinal region bypassing the harsh acidic environment of the stomach has long been a research focus. On the other hand, monitoring a system’s pH during drug delivery is a crucial diagnosis factor as the activity and release rate of many therapeutics depend on it. This study answered both of these issues by fabricating a novel nanocomposite hydrogel for intestinal drug delivery and near-neutral pH sensing at the same time. Gelatin nanocomposites (GNCs) with varying concentrations of carbon dots (CDs) were fabricated through simple solvent casting methods. Here, CDs served a dual role and simultaneously acted as a cross-linker and chromophore, which reduced the usage of toxic cross-linkers. The proposed GNC hydrogel sample acted as an excellent pH sensor in the near-neutral pH range and could be useful for quantitative pH measurement. A model antibacterial drug (cefadroxil) was used for the in vitrodrug release study at gastric pH (1.2) and intestinal pH (7.4) conditions. A moderate and sustained drug release profile was noticed at pH 7.4 in comparison to the acidic medium over a 24 h study. The drug release profile revealed that the pH of the release medium and the percentage of CDs cross-linking influenced the drug release rate. Release data were compared with different empirical equations for the evaluation of drug release kinetics and found good agreement with the Higuchi model. The antibacterial activity of cefadroxil was assessed by the broth microdilution method and found to be retained and not hindered by the drug entrapment procedure. The cell viability assay showed that all of the hydrogel samples, including the drug-loaded GNC hydrogel, offered acceptable cytocompatibility and nontoxicity. All of these observations illustrated that GNC hydrogel could act as an ideal pH-monitoring and oral drug delivery system in near-neutral pH at the same time.

We herein report a cell-membrane-permeable molecular probe ADG, prepared by conjugating guanosine with anthracene, selectively interacts with c-MYCG-quadruplex over other promoter and telomeric quadruplexes as well as duplex DNA. NMR spectroscopy suggests that ADGinteracts with terminal G-quartets as well as with the nearby G-rich tract (G13-G14-G15 and G8-G9-G10) of c-MYCquadruplex. In vitro cellular studies indicate that ADGrepresses c-MYCexpression by stabilizing its promoter G-quadruplex and alters c-MYC-related cellular events. ADGsuppresses hTERTand BCL2gene expressions in a promoter-independent manner, inhibits elongation of telomere length, and activates apoptotic cascades in cancer cells.

We herein delineate an unexplored reactivity of 3-hydroxyoxindoles toward Grignard addition enabling a rapid access to a broad range of unnatural C2-quaternary 2-hydroxyindoxyls in high yields. The reaction proceeds via a mechanistically intriguing one-pot 1,2-hydride shift followed by autoxidation pathway. The utility of this method is demonstrated by the synthesis of a new class of bis-indoxyl spirofuran derivatives.

This work discloses transamidation of primary and tertiary amides with a range of aryl, heteroaryl, and aliphatic amines using potassium tert-butoxide. The reaction proceeds at room temperature under transition-metal-free conditions providing secondary amides in high yields. Moreover, reaction of cyclopropyl amine with tertiary amides proceeds with ring-opening to provide a rapid access to enamides.

Herein, we develop a competitive screening method in which G-quadruplex DNA linked magnetic nanoparticles pull down selective ligands for a particular quadruplex topology from a series of small molecules. The screening strategy is first optimized with known G-quadruplex ligands and then used with a new series of G-quadruplex interactive bis-triazolyl ligands that are synthesized by Cu(I)-catalyzed azide–alkyne cycloaddition. The assay enables the identification of c-MYCand BCL2G-quadruplex selective bis-triazole ligands that specifically target promoter G-quadruplexes in cancer cells.

Dynamic combinatorial chemistry (DCC) has emerged as a promising strategy for template-driven selection of high-affinity ligands for biological targets from equilibrating combinatorial libraries. However, only a few examples using disulfide-exchange-based DCC are reported for nucleic acid targets. Herein, we have demonstrated that gold-coated magnetic nanoparticle-conjugated DNA targets can be used as templates for dynamic selection of ligands from an imine-based combinatorial library. The implementation of DCC using DNA nanotemplates enables efficient identification of the lead compounds, from the dynamic combinatorial library via magnetic decantation. It further allows quick separation of DNA nanotemplates for reuse in DCC reactions. The identified lead compound exhibits significant quadruplex versus duplex DNA selectivity and suppresses promoter activity of c-MYCgene that contains G-quadruplex DNA forming sequence in the upstream promoter region. Further cellular experiments indicated that the lead compound is able to permeate into cell nuclei and trigger a DNA damage response in cancer cells.

We present a transition metal‐free direct C‐2 hydroxymethylation of thiazoles using ketones in the presence of KOtBu, leading to the synthesis of thiazole‐2‐diarylcarbinols. The regioselective deprotonation promotes the Csp2−Csp3 bond formation, resulting in the creation of a quaternary centre. The method offers a complementary strategy to traditional cross‐coupling technologies utilizing azole halides and organometallic reagents, thereby expanding the substrate scope. Furthermore, benzothiazoles exhibit compatibility under the mild reaction conditions. Moreover, this method enables the synthesis of thiazolyl diarylcarbinols and bioactive compounds on a multigram scale. A transition metal‐free direct C‐2 hydroxymethylation of thiazoles with ketones in the presence of KOtBu to construct thiazole‐2‐diarylcarbinols is delineated. Complementary to cross‐coupling technologies with azole halides and organometallic reagents, the method has a broad substrate scope. The synthetic route also accommodates benzothiazoles and provides an access to multigram‐scale synthesis of thiazolyl diarylcarbinols and bioactive compounds.

We herein synthesize a bisindole enyne using the iron-catalyzed environmentally benign dimerization method. The enyne kills cancer cells by arresting the cell cycle at the G2/M phase via the necroptosis pathway, a non-apoptotic form of cell death that is also considered a promising and attractive pathway to induce cancer cell death. The inherent fluorescent property has been used to study its localization in cells and its binding interactions with genomic DNA. This work demonstrates bisindole enyne motifs could be a new pharmacophore for developing anticancer agents.

The previously unexplored Grignard addition to oxindoles provides a regiospecific approach to 2- and 2,3-disubstituted indole derivatives in high yields via a one-pot aromatization driven dehydration pathway. This method allows a convenient preparation of diallyl indoles that are used as ring-closing metathesis (RCM) precursors for the orthogonal synthesis of pyrido[1,2-a]indoles and carbazoles. The synthetic utility of this method is illustrated by the synthesis of a microtubulin inhibitor and naturally occurring carbazole alkaloids.

G-quadruplexes have been considered attractive therapeutic targets for the development of anticancer agents. We herein report synthesis of a series of carbazole derivatives by employing modular one-pot Cu(I) catalyzed cycloaddition. These carbazole derivatives are easily synthesizable, soluble in aqueous media, and able to strongly interact with quadruplexes. FRET based melting assay and fluorescence titration experiments suggest that a carbazole derivative, Cz-1, preferentially binds c-MYCquadruplex DNA over other investigated quadruplex and duplex DNAs. The biological studies revealed that Cz-1inhibits cancer cell proliferation by inducing apoptosis. Moreover, Cz-1inhibits the expression of c-MYCat transcriptional as well as translational levels. Exon-specific-assay confirms that the downregulation of MYCexpression is mainly driven by the binding of Cz-1with the promoter G-quadruplex structures. Immunocytochemistry, using quadruplex binding antibody BG4, further suggests that Cz-1induces and stabilizes G-quadruplexes in a cellular system.

The Ullmann-type cross coupling of a variety of aromatic, aliphatic amines with aryl halides is reported using a CuI-based catalytic system in combination with an easily accessible prolinamide ligand in aqueous media. The method is mild and tolerant to air, moisture, and a wide range of functional groups, providing a novel way to access a variety of aminated products. Secondary amines like heteroaromatic amines and nucleobases have also been used, affording the corresponding coupling products in good to excellent yields. Moreover, this method has been employed for chemoselective C–N arylation of aminophenols and further utilized for the synthesis of carbazole natural products, avoiding the protection and deprotection steps.

In this study, we present a novel and cost-effective approach for synthesizing biologically significant analogues of rutaecarpine alkaloid through a one-step cascade reaction. The pentacyclic core of rutaecarpine alkaloid analogues is efficiently constructed using 2-aminobenzonitriles and substituted indole-2-carbaldehydes in the presence of the affordable base KOtBu. The salient feature of this approach is the promotion of a sequential cascade process within a single reaction vessel including the formation of a dihydroquinazolinone ring, oxidation, and cyclization. This method can be successfully applied on a larger scale, making it economically viable.

Synthetic ion channels are used to study biological processes and develop sensing, drug delivery and antimicrobial systems. This protocol uses click chemistry to prepare lipophilic diguanosine derivatives that assemble into metal cation channels.

Aromatic, heteroaromatic and sulfonyl azides were conveniently reduced to the corresponding amines in excellent yields using hydrazine hydrate in the presence of iron oxide nanoparticles. The Fe3O4-MNPs could be easily separated by an external magnet, and recycled ten times without significant loss of the catalytic efficiency.

Transparent self‐standing supramolecular hydrogels were readily prepared by the potassium‐ion‐mediated self‐organization of guanosine and 8‐bromoguanosine whilst the individual components precipitated within a few hours. VT‐NMR spectroscopy showed that bromoguanosine was a superior gelator compared to guanosine. XRD analysis showed that gel formation was caused by stacked G‐quartets. AFM analysis revealed dendritic architectures of the nanofibers in the two‐component hydrogel network. DSC profiles showed that the hybrid hydrogels underwent sol–gel transition at lower temperature than the pure guanosine and bromoguanosine hydrogels. Interestingly, bioactive dyes, such as rose bengal, rhodamine‐6‐G, and fluorescein, could be diffused and released in a controlled manner. UV/Vis absorption and fluorescence spectroscopy and CLSM were used to investigate the diffusion behavior of dyes in the hydrogel network. These dyes exhibited strong birefringence in the gel network (0.07–0.1) as a result of the anisotropic organization.

The design and synthesis of a series of bis‐indole carboxamides with varying amine containing side chains as G‐quadruplex DNA stabilising small molecules are reported. Their interactions with quadruplexes have been evaluated by means of Förster resonance energy transfer (FRET) melting analysis, UV/Vis spectroscopy, circular dichroism spectroscopy and molecular modelling studies. FRET analysis indicates that these ligands exhibit significant selectivity for quadruplex over duplex DNA, and the position of the carboxamide side chains is of paramount importance in G‐quadruplex stabilisation. UV/Vis titration studies reveal that bis‐indole ligands bind tightly to quadruplexes and show a three‐ to fivefold preference for c‐kit2over h‐teloquadruplex DNA. CD studies revealed that bis‐indole carboxamide with a central pyridine ring induces the formation of a single, antiparallel, conformation of the h‐teloquadruplex in the presence and absence of added salt. The chirality of h‐teloquadruplex was transferred to the achiral ligand (induced CD) and the formation of a preferred atropisomer was observed.

A small molecule based on bisphenylethynyl amide meta linked to 2,6-pyridine can induce cyclodextrin (CD) aggregation through a possible 1:3 guest–host motif. Most of the small molecules induce CD nanotubular bundles principally through 1:2 guest–host unit capsules and aggregate through hydrogen bonding among the hydroxyl groups present on the rims of the CD molecules. The N,N-dimethyl aminopropyl carboxamide side chain and the central pyridine ring of 6-bromo-2-phenylethylaminopyridine (BPEAP) induces nanotubular bundles with α-CD and laminar bundles with β- and γ-CDs, which, as a consequence, may result in formation of pores in the aggregates that can find wide applications in biological storage machinery. The stoichiometry of the ingredients of the unit capsules has been evidenced by Job’s plot. The size-dependent suprastructures induced by BPEAP have been studied by steady state and time-resolved fluorescence spectroscopy and atomic force microscopy.

Herein, we report the design, synthesis and biophysical evaluation of novel 1,2,3‐triazole‐linked diethynyl‐pyridine amides and trisubstituted diethynyl‐pyridine amides as promising G‐quadruplex binding ligands. We have used a CuI‐catalysed azide–alkyne cycloaddition click reaction to prepare the 1,2,3‐triazole‐linked diethynyl‐pyridine amides. The G‐quadruplex DNA binding properties of the ligands have been examined by using a Förster resonance energy transfer (FRET) melting assay and surface plasmon resonance (SPR) experiments. The investigated compounds are conformationally flexible, having free rotation around the triple bond, and exhibit enhanced G‐quadruplex binding stabilisation and specificity between intramolecular promoter G‐quadruplex DNA motifs compared to the first generation of diarylethynyl amides (J. Am. Chem. Soc.2008, 130, 15 950–15 956). The ligands show versatility in molecular recognition and promising G‐quadruplex discrimination with 2–50‐fold selectivity exhibited between different intramolecular promoter G‐quadruplexes. Circular dichroism (CD) spectroscopic analysis suggested that at higher concentration these ligands disrupt the c‐kit2 G‐quadruplex structure. The studies validate the design concept of the 1,3‐diethynyl‐pyridine‐based scaffold and demonstrate that these ligands exhibit not only significant selectivity over duplex DNA but also variation in G‐quadruplex interaction properties based on small chemical changes in the scaffold, leading to unprecedented differential recognition of different DNA G‐quadruplex sequences.

Simple, but yet unknown: 1,3‐Diketones, ammonia, and carboxylic acids are the precursors for the efficient synthesis of 4‐hydroxypyridines and the corresponding nonaflate derivatives. This provides simple and practical access to a variety of highly substituted pyridine derivatives, including antibiotic natural products such as caerulomycins A, E and functionalized terpyridines (see scheme).

A series of 4‐pyridyl nonaflates was coupled with several terminal alkynes to efficiently provide new 4‐alkynyl‐substituted 3‐alkoxypyridine derivatives. Apt conditions were developed for their conversion into furo[2,3‐c]pyridines. Sonogashira reactions of 4‐alkoxy‐substituted 3‐pyridyl nonaflates allowed an access to regioisomeric furo[3,2‐c]pyridines. For both types of alkynyl‐substituted alkoxypyridinesan alternative method for cyclization employing iodine monochloride furnished iodinated furo[2,3‐c]‐ or furo[3,2‐c]pyridines, which can undergo a second palladium‐catalyzed step. Iodination of 4‐hydroxypyridine derivative 24with iodine afforded a pentasubstituted pyridine which after Sonogashira reaction immediately undergoes a cyclization to furo‐pyridine 25. Thus, three different types of furo‐pyridines can be prepared starting from one precursor. Several compounds prepared are fluorescent and show strong Stokes shifts. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) A series of 4‐pyridyl nonaflates was coupled with alkynes to efficiently provide new4‐alkynyl‐substituted pyridines. Apt conditions were developed for their conversion into furo[2,3‐c]pyridines. 3‐Pyridyl nonaflates offer access to regioisomeric furo[3,2‐c]pyridines. An alternative cyclizationmethod employing iodine monochloride furnishes iodinated furo‐pyridines which can undergo a second Pd‐catalyzed step. Some of the newly prepared compounds are fluorescent and show strong Stokes shifts.

The application of olefin cross-metathesis to vinyl-functionalized thiazoles and the tandem Stille coupling/cross-metathesis of bis-trifloylthiazoles are reported. These processes offer new opportunities for the synthesis of complex natural products.

Addition of lithiated methoxyallene to pivalonitrile afforded after aqueous workup the expected iminoallene 1in excellent yield. Treatment of this intermediate with silver nitrate accomplished the desired cyclization to the electron‐rich pyrrole derivative 2in moderate yield. Surprisingly, trifluoroacetic acid converted iminoallene 1to a mixture of enamide 3and trifluoromethyl‐substituted pyridinol 4(together with its tautomer 5). A plausible mechanism proposed for this intriguing transformation involves addition of trifluoroacetate to the central allene carbon atom of an allenyl iminium intermediate as crucial step. Enamide 3is converted to pyridinol 4by an intramolecular aldol‐type process. A practical direct synthesis of trifluoromethyl‐substituted pyridinols 4, 10, 11, and 12starting from typical nitriles and methoxyallene was established. Pyridinol 10shows an interesting crystal packing with three molecules in the elementary cell and a remarkable helical supramolecular arrangement. Trifluoromethyl‐substituted pyridinol 4was converted to the corresponding pyridyl nonaflate 13, which is an excellent precursor for palladium‐catalyzed reactions leading to pyridine derivatives 14–16in good to excellent yields. The new synthesis of trifluoromethyl‐substituted pyridines disclosed here demonstrates a novel reactivity pattern of lithiated methoxyallene which is incorporated into the products as the unusual tripolar synthon B.

We report a highly regio- and diastereoselective allylindium addition to norbornyl α-diketones that leads to acyloins. The diastereoselection in the case of monosubstituted derivatives greatly depends on the nature of the 5-endo substituents. Non-chelating groups direct the addition from the sterically less congested exo-face, diagonal to the substituent, while chelating substituents, such as an alkoxy or acetoxy units, induce a complete reversal in the selectivities. The presence of an oxygen atom directly linked to the norbornyl framework is crucial for eliciting a chelating effect because an acetoxymethyl (−CH2OAc) group exhibits normal behavior and acts as a non-chelating group. The dramatic influence (reversal) of an apparently innocuous exo-Me substituent is noted. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

A novel, efficient, and regio‐ as well as diastereoselective conversion of non‐enolizable bicyclic α‐diketones into synthetically useful acyloins mediated by indium metal is described. The reduction is highly diastereoselective, leading exclusively to endo‐acyloins (endo‐hydroxyl groups) in excellent yields, and tolerates a variety of sensitive substituents, such as acetate, ester, and bridgehead halogens. The regioselectivity in the reductions of monosubstituted α‐diketones varied from 70:30 to 100:0 for the two possible isomeric alcohols. The methodology is extended to the synthesis of highly functionalized cyclopentane carboxaldehydes, potential building blocks in organic syntheses, by cleavage of the acyloins by treating them with Pb(OAc)4in MeOH/PhH. Allylindium additions to carboxaldehydes 22have been found to be highly diastereoselective.

A novel, efficient, and regio- as well as diastereoselective conversion of non-enolizable bicyclic α-diketones into synthetically useful acyloins mediated by indium metal is described. The reduction is highly diastereoselective, leading exclusively to endo-acyloins (endo-hydroxyl groups) in excellent yields, and tolerates a variety of sensitive substituents, such as acetate, ester, and bridgehead halogens. The regioselectivity in the reductions of monosubstituted α-diketones varied from 70:30 to 100:0 for the two possible isomeric alcohols. The methodology is extended to the synthesis of highly functionalized cyclopentane carboxaldehydes, potential building blocks in organic syntheses, by cleavage of the acyloins by treating them with Pb(OAc)4 in MeOH/PhH. Allylindium additions to carboxaldehydes 22 have been found to be highly diastereoselective.

Lithium-zinc ferrite thin films have been deposited by rf sputtering technique on amorphous fused quartz substrates. The as-deposited films were amorphous and crystallization took place when the films were annealed at 800°C. The observed magnetization values varied from 34 to 60% of that of the bulk. The coercivity was found to be in the range 35–42 Oe.

The preparation of Pd‐nanoparticles embedded into the polymer matrix of poly(1,4‐phenylene sulfide) via the thermolysis of palladium acetate is described.

It allows a new access to 1‐thia‐3‐azaspiro[4.4]nonene and [4.5]decene ring systems.

The present new three‐component reactions of lithiated alkoxyallene (I) and (XIX) with nitriles and carboxylic acids provide highly functionalized ‐alkoxy‐‐ketoenamides (IV) and (X) which are further cyclized into different pyridine derivatives.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.