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A protocol for synthesizing symmetrical thioethers by using a cheap organosulfur reagent (tetramethylthiuram monosulfide: TMTM) was developed. Both iodobenzenes and phenylboronic acids react well with TMTM, giving the target products with good to excellent yields. This method features simple performance, wide functional group tolerance, and good to excellent yields, showing a potential application value for the synthesis of drug molecules. [ABSTRACT FROM AUTHOR]

A highly efficient method for the synthesis of S -aryl dithiocarbamates is reported. By using tetramethylthiuram monosulfide (TMTM) and aryl boronic acids as starting materials, C(sp2)–S bond-forming reactions proceed smoothly to give the desired aryl dithiocarbamates in good to excellent yields. The methodology features a simple procedure, broad functional group tolerance and excellent yields, whilst showing potential synthetic value for the preparation of a diverse range of biologically and pharmaceutically active compounds. [ABSTRACT FROM AUTHOR]

After binding to human serum albumin, bilirubin could undergo photoisomerization and photo-induced cyclization process. The latter process would result the formation of a product, named as lumirubin. These photo induced behaviors are the fundamental of clinical therapy for neonatal jaundice. Previous studies have reported that the addition of long chain fatty acids is beneficial to the generation of lumirubin, yet no kinetic study has revealed the mechanism behind. In this study, how palmitic acid affects the photochemical reaction process of bilirubin in Human serum albumin (HSA) is studied by using femtosecond transient absorption and fluorescence up-conversion techniques. With the addition of palmitic acid, the excited population of bilirubin prefers to return to its hot ground state (S0) through a 4 ps decay channel rather than the intrinsic ultrafast decay pathways (<1 ps). This effect prompts the Z-Z to E-Z isomerization at the S0 state and then further increases the production yield of lumirubin. This is the first time to characterize the promoting effect of long chain fatty acid in the process of phototherapy with femtosecond time resolution spectroscopy and the results can provide useful information to benefit the relevant clinical study. [ABSTRACT FROM AUTHOR]

Organometallic compounds have become increasingly important in organic synthesis because of their high chemoselectivity and excellent reactivity. Recently, a variety of organometallic reagents were found to facilitate transition-metal-catalyzed cross-coupling reactions and nucleophilic addition reactions. Here, we have summarized the latest progress in cross-coupling reactions and in nucleophilic addition reactions with functionalized organometallic reagents present to illustrate their application value. Due to the tremendous contribution made by the Knochel group towards the development of novel organometallic reagents, this review draws extensively from their work in this area in recent years. Introduction 1 Transition-Metal-Catalyzed Cross Couplings Involving Organo-zinc Reagents 2 Transition-Metal-Catalyzed Cross Couplings Involving Organomagnesium Reagents 3 Transition-Metal-Free Cross Couplings Involving Zn and Mg -Organometallic Reagents 4 Nucleophilic Additions Involving Zn and Mg Organometallic Reagents 5 Cross-Coupling Reactions or Nucleophilic Additions Involving Mn, Al-, La-, Li-, Sm- and In-Organometallics 6 Conclusion [ABSTRACT FROM AUTHOR]

A highly efficient three-component protocol for the synthesis of the 2-alkylthiobenzoazoles is described. Tetramethylthiuram disulfide (TMTD) cyclized with o -aminothiophenols, generating the intermediate 2-mercaptobenzothiazoles, and the successive C–S coupling with halogenated alkanes afforded a series of 2-alkyl-substituted thiobenzothiazoles smoothly in a one-pot process. This procedure could also be utilized for the preparation of 2-alkyl-substituted thiobenzoxazoles and 2-alkyl-substituted thiobenzimidazoles. Inexpensive and easily available starting materials, metal catalyst-free, broad substrate scope, and water as solvent are the features of this protocol. [ABSTRACT FROM AUTHOR]

A new technique for constructing representations of point groups, called symmetrized boson representation is introduced. This method is particularly useful when describing vibrations of large molecules and for high overtones. The method is illustrated by applying it to stretching overtones of octahedral molecules, SF6, WF6, and UF6 with group Oh. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]