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This paper discusses recent efforts to control magnetism with electric fields in single and multilayer oxides, which has great potential to improve a variety of technological endeavors, such as magnetic sensing and magnetoelectric (ME) logic. The importance of electrical control of magnetism is followed by a discussion of multiferroics and MEs, which are the leading contenders for this task. The focus of this paper is on complementary methods in understanding the ME coupling, an essential step to electrical control of magnetism. Neutron scattering, nonlinear optics and X-ray spectromicroscopy are addressed in providing key parameters in the study of ME coupling. While primarily direct (single-phase multiferroics) ME materials are used as examples, the techniques discussed are also valuable to the study of indirect (e.g., multilayers and pillars) magnetoelectrics. We conclude with a summary of the field and future directions.

Amine-mediated three-component reaction of 1,3-diketones with acetylenedicarboxylate (II) and malononitrile or cyanoacetate under neat conditions provides a novel atom-efficient access towards chromenes (IV) and (VI), respectively.

TMSCI accelerates the conjugate addition of in situ prepared organosamarium regents to α,β-unsaturated carbonyl compounds and nitriles in the presence of HMPA and catalytic amounts of Cu(I) salts. Reactions at -78 o C leads to silyl enol ethers which are isolated or cleaved with TBAF to give β-alkylated ketones in 30-90% overall yield. Catalysis is most efficient in the presence of 4 equiv of TMSCl and HMPA. HMPA is also necessary for the in situ preparation of the organosarium species from alkyl halide and SmI 2

Conversion of tritylated 2-methylglycidol to the corresponding aziridine occurs by Staudinger cyclization of the intermediate azido alcohol. After N -sulfonylation with Ses-Cl and ring-opening with benzyl alcohol, oxidation of the primary alcohol provides N , O -bisprotected α-methylserine directly suitable for repetitive peptide synthesis. This sequence represents a general enantioselective protocol for the synthesis of α-methylserine and other α,α-disubstituted amino acids.

A direct oxazoline→thiazoline conversion can be realized by thiolysis of oxazolines with H2S in methanol/triethylamine, followed by cyclodehydration with Burgess reagent. This protocol is high-yielding, chemoselective, and essentially free of racemization for C(5)-unsubstituted and trans-4,5-disubstituted peptide oxazolines. Thioamide intermediates are obtained regioselectively, thus the thiolysis of oxazolines offers an alternative to the thiation of peptides with Lawesson's reagent.

The reactivity profile of glycine Schiff's bases with crotonate and bromocrotonate has been shown to take a different course depending on the choice substituent on the imine. Application of the above study for the mild and concise synthesis of CCG-II has been achieved.

A polyethyleneglycol-linked version of Burgess reagent was developed and applied toward the cyclodehydration of β-hydroxy amides and thioamides. The desired oxazolines and thiazolines were obtained in high yields and excellent purities. The major advantages of the polymer bound reagent are its improved ease of handling and greatly increased yields in the synthesis of labile oxazolines.

The recently isolated cyanobacterium metabolite muscoride A was synthesized in 15 steps and in 4.3% overall yield. Novel structural features of this peptide antibiotic include the presence of a threonine-derived bioxazole core and an N-(1,1-dimethyl)allyl (“reverse prenyl”) valine residue. In the context of our synthesis, efficient new strategies for the preparation of these segments were developed. The synthesis of two epimers of muscoride A allowed the unambiguous assignment of the relative and absolute configuration of the natural product by NMR and optical rotation analyses.

Enantiomeric excess of scalemic ( i.e nonracemic, 17–86 % ee) 1,1′-bi-2-naphthol are readily enhanced to 90–96 % ee by refluxing with B(OH) 3 and TMEDA in acetonitrile, followed by acid hydrolysis of the precipitate.

Oxidation of benzylic methylenes in polycyclic systems to the benzylic ketones was carried out with sodium bismuthate in the presence of acetic acid.

A simple method for the reduction of aromatic nitro compounds to aromatic amines was developed using samarium and catalytic amounts of iodine.

A practical and efficient synthesis of (±)-camptothecin from glycine via an intramolecular Michael addition is described.

A bioactivity-directed fractionation of the extracts of the Malaysian plant Garcinia pavifolia and a phytochemical study of G. griffithii led to the discovery of griffipavixanthone (1), a novel cytotoxic bixanthone with cyclized prenyl groups providing the xanthone-xanthone linkage. Spectroscopic data and preparation of methylated derivatives allowed for the complete structural elucidation of 1.

In air and water, trialkylphenyl- or trialkylvinylstannanes react with α,β-unsaturated esters and ketones to give the corresponding conjugated addition products in high yields in the presence of a rhodium catalyst.

The construction of complex protein folds relies on the precise conversion of a linear polypeptide chain into a compact 3-dimensional structure. The interplay of forces that link sequence and folding is intricate and yet to be firmly elucidated. Examination of protein 3-dimensional structures suggests that complex tertiary folds and quaternary associations can be deconstructed into a limited number of secondary structural elements, such as strands, helices, and turns, which are assembled using loosely structured loops (Figure 1). The stability of a specific fold is determined by tertiary interactions between residues which are distant in sequence. De novo design of existing or novel protein folds demands a thorough understanding of the rules that underlie protein structure and stability.

A facile conversion of aromatic aldehydes to esters using molecular sieves, TS-1, and 30% H 2 O 2 is described.

Transition-metal catalysis is out-grown from dry-boxes where the use of inert gas atmosphere and the exclusion of moisture have been essential. Such a restriction undoubted- ly imposes limitations in the application of these reactions in organic synthesis and in the recycling of the catalysts. This article discusses some recent advances of rhodium-catalyzed carbon-carbon bond formations under the natural conditions of air and water.

Successful syntheses of two new aromatic core modified oxybenziporphyrins by a simple '3 + 1' methodology and the first aromatic core modified oxybenziporphyrin palladium complex are reported.

Palladium-catalyzed reactions in general are carried out under an inert atmosphere because the palladium intermediates involved in the catalytic cycles are often known to be sensitive to oxygen. In this paper, we report that various palladium-catalyzed reductive couplings proceed smoothly under an air atmosphere and in aqueous medium. Under the air atmosphere reaction conditions, palladium-triphenylphosphine complex was found to be inactive. By using zinc as the reducing reagent, aryl halides were homo-coupled to give symmetrical biaryls either in aqueous acetone or in water in the presence of a catalytic amount of 18-crown-6 at room temperature. Both aryl iodides and aryl bromides reacted efficiently under the current reaction conditions. The reaction of arylhalosilanes with aryl halides under refluxing conditions in air and water catalyzed by palladium generated unsymmetrical biaryls efficiently in the presence of either KOH or NaF. Such air-stable couplings are also suitable for a Suzuki-type coupling and a Stille-type coupling.

Enzyme‐catalyzed efficient synthesis of (1R)‐[3,5‐bis (trifluoromethyl) phenyl] ethanol (R)‐(3), a key intermediate for aprepitant, via enantioselective transesterification of racemic 1‐[3,5‐bis (trifluoromethyl) phenyl] ethanol (RS)‐3 using vinyl acetate as the acyl donor in the presence of Candida antarctica lipase‐B (CAL‐B) in an overall yield of 84% with >99% ee is described.

A simple and new synthetic approach to various analogues of Irbesartan is described. DRL Pub. No. IPDO‐IPM 00018

The discovery of the clinical effectiveness of erythromycin and azithromycin in inflammatory airway diseases has inspired the discovery and development of macrolides with selective immunomodulatory activity. Erythromycin degradation continues to be a source of novel macrolides with a variety of selective biological activities. New technologies for drug discovery based in the emerging field of combinatorial biosynthesis provide the medicinal chemist with novel approaches toward the discovery of novel macrolides. Recent efforts to integrate synthetic organic medicinal chemistry with combinatorial biosynthesis have expanded the number of techniques available for macrolide synthesis.

[reaction: see text] A highly stereoselective synthesis of beta-amino sulfones and sulfonamides via addition of sulfonyl anions to chiral N-sulfinyl imines is described. The addition reaction proceeds in good yield (75-99%) and stereoselectivity.

Prolonged hepatitis C infection is the leading cause for cirrhosis of the liver and hepatocellular carcinoma. The etiological agent HCV virus codes a single polyprotein of approximately 3000 amino acids that is processed with the help of a serine protease NS3A to produce structural and non-structural proteins required for viral replication. Inhibition of NS3 protease can potentially be used to develop drugs for treatment of HCV infections. Herein, we report the development of a series of novel NS3 serine protease inhibitors derived from 2-aza-bicyclo[2.2.1]-heptane carboxylic acid with potential therapeutic use for treatment of HCV infections.

Facile synthetic approaches toward the preparation of ABC ring of camptothecin and related alkaloids starting from cheaper and readily available chemical reagents.

Even though the first expanded porphyrin was reported in the mid-1960s, the advances in its chemistry are more recent. New and powerful synthetic methods have facilitated the availability in affordable quantities of expanded porphyrins in general and core modified systems in particular. This has stimulated interest in studying various properties pertaining to their potential applications in biomedicine and materials chemistry. In this Account, we not only summarize the details of the synthetic methodologies reported, but we also highlight studies that focus on the structural diversity, aromaticity, and anion and cation binding abilities of expanded porphyrins.

In the presence of a rhodium catalyst, α,β-unsaturated esters and ketones react with triphenylbismuth in aqueous media and under an air atmosphere to give the corresponding conjugated addition products in high yields.

Synthesis of porphyrins containing one to four ferrocenyl groups on the meso carbons is reported.

A simple and readily available oxidation of primary allylic and benzylic alcohols to the corresponding aldehydes is carried out by sodium bismuthate in acetic acid.

In the presence of a catalytic amount of 18-crown-6, palladium-catalyzed reductive coupling of aryl halides mediated by zinc was found effective in water alone, at ambient temperature, and under an atmosphere of air to give improved isolated yield of the Ullmann-type reaction products.