Search

The Bowei Research Conference (BRC) series, established by Mr. Bowei Lee in Taiwan, provides a platform for young scientists, postdoctoral fellows, and graduate students to network and exchange ideas. The article highlights past conferences, such as BRC-2 and BRC-3, and the upcoming BRC-4 conference with the theme "The Magic of Synthesis - New Frontiers of Molecular Architecture." The LCY Group and the LCY Education Foundation organize and sponsor the BRC series. The opening ceremony of BRC-4 featured distinguished guests, a buffet dinner, and traditional Chinese music, emphasizing the importance of chemistry in solving global challenges and promoting innovation. Keynote lectures covered topics like sustainable chemistry, natural product synthesis, and molecular machines, providing valuable insights into advancements in the field. The conference also included a poster session and retreat activities, and the next conference, BRC-5, will focus on "The Magic of Chemical Biology." [Extracted from the article]

Richard was mainly known as a gifted scientist, a charismatic leader, and an original and creative President. And he was my good friend and a role model for over three decades. The term impossible was not part of his vocabulary. I′ve learned from him that there is no limit to imagination and creativity, no limit to the number of assignments one can fulfill, and no limit to the magnitude of a dream one can turn into reality. Richard was blessed with the unique talent to quickly decipher the essence of people's thoughts and discover the hidden parts of their personalities, which allowed him to focus on what he defined as the most valuable issues and productive discussions. My experience with him included the joy of scientific discovery, the silent mode of human communication, the power of commitment and dedication, and the wildest sense of humor. Now, nearly two years after his departure, I feel free and obliged to share unknown stories and anecdotes that illuminate various facets of his personality. [ABSTRACT FROM AUTHOR]

The Annual Wolf Prize Symposia of the Israel Chemical Society (ICS) have become a significant component of the scientific landscape of the State of Israel. These highly attended events occur annually in late May or early June as part of the Wolf Prize week, usually one day before the award ceremony in the Knesset. This account covers the one‐day symposium at the Weizmann Institute of Science on June 14, 2023, the Wolf Prize ceremony in the Knesset on June 15, and several other events in Israel that week, all honoring Chuan He, Jeffrey W. Kelly, and Hiroaki Suga. [ABSTRACT FROM AUTHOR]

The imidazolopyridine-based carbenes used by Prof. Shibahara are mentioned in the context of fused polyaromatic NHC ligands used in -acid catalysis in a review by Vincent César. -acid catalysis is one of the last two decades' most exciting developments in synthetic organic chemistry. Surprisingly, despite the prominent role of Au in -acid catalysis in general, chiral gold catalysts have received much less attention. [Extracted from the article]

This report covers two exciting events in the scientific landscape of the State of Israel: the traditional Wolf Prize Symposium of the ICS and the Wolf Prize Ceremony in the Knesset. The symposium, dedicated to the science of Stephen L. Buchwald and John F. Hartwig, highlighted the catalytic formation of C−N bonds. In a general sense, the two Wolf Prize laureates may be considered as molecular architects who produced efficient molecular‐scale machines that make important molecules for the benefit of humanity. After receiving the Wolf Prize from Israel's President, Buchwald commented, "There are many who believe that support for research should focus exclusively on endeavors that have specific practical applications in mind. With this mindset, our work would have never been possible. Time and time again experience shows that it is exceedingly difficult to predict which scientific discoveries will lead to major advances. So often, it is the scientist following his or her own intellectual curiosity whose work leads to a breakthrough. I believe that basic curiosity‐driven research and societal and economic progress are inextricably linked." And Hartwig comments, "We all know the principles of science know no boundaries, but maybe less appreciated, or taken for granted, is that the assembly of research teams in many places knows no boundaries. If we recognize and nurture talent in people from all corners and all backgrounds we can address and maybe solve today's most important problems in health, energy, and environmental sustainability that are urgently facing us." [ABSTRACT FROM AUTHOR]

Keinan belonged to the University of Wisconsin era (Figure 1) and was working on Pd-catalyzed allylation reactions (1977-79), while Portnoy worked at Stanford on Ru-catalyzed enone-alkyne coupling reactions (1995-97). These "less famous" synthetic methods, which include metal-catalyzed alkyne-alkyne and alkyne-alkene couplings, as well as reduction/oxidation reactions, were used for the total synthesis of a variety of natural products, pharmaceuticals, and other complex bioactive molecules. This chemistry enabled unprecedented reactions and products, such as 1,5-dicarbonyl compounds, [2+2+2] cycloaddition of alkynes to 1,5-cyclooctadiene, and a [5+2] cycloaddition to form seven-membered rings. [Extracted from the article]

Unlike other major cities of the Biblical era, the actual site of the city of Ephraim, which is of fundamental significance to early Hebrew history, is still a mystery. We examined the reported attempts to locate the city, concluding that the commonly accepted theory, which identifies it as the modern village of et-Tayibeh on a hilltop north of Jerusalem, is highly unlikely. All available evidence indicates that the correct location is Khirbet Marjameh near Kafr Malik, as originally suggested in 1922 by W. F. Albright. Although much archaeological evidence has accumulated since 1922, Albright's proposal is the most probable of all theories suggested so far. Since the city of Ephraim was an important Hebrew centre in the pre-Israelite period, this site may have played a significant role in the dawn of Hebrew history. Furthermore, Albright's localisation of Rachel's tomb, one of the holiest sites in Judaism, within the necropolis of Wadi Samiyeh seems plausible. [ABSTRACT FROM AUTHOR]

The human population, doubling every 50 years, creates global problems, including limitations on energy, raw materials, food, water, health, and air. However, the future of humankind seems bright thanks to the even faster growth of human knowledge, doubling every 18 months, and the unpredictability of science. Our global challenges are likely to be met by yet unknown technologies, mostly invented by chemists. [ABSTRACT FROM AUTHOR]

Das Bevölkerungswachstum, welches sich alle 50 Jahre verdoppelt, führt zu globalen Problemen wie Energie ‐ , Rohstoff ‐ und Lebensmittelknappheit. Dennoch erscheint durch das schnelle Wachstum des menschlichen Wissens, das sich alle 18 Monate verdoppelt, und durch die Unvorhersagbarkeit der Wissenschaft die Zukunft der Menschheit heller. Unsere globalen Herausforderungen werden wahrscheinlich durch bisher noch unbekannten Technologien, meist von Chemikern entwickelt, gelöst werden. [ABSTRACT FROM AUTHOR]

The article offers information on the 75th Annual Meeting of the Israel Chemical Society to be held at Tel Aviv, Israel on January 25-26, 2010.

Information about several papers discussed at the third International Symposium on Bio-Inspired Engineering (ISBIE) is presented. The symposium was conducted on October 21, 2009 in Taipei, Taiwan. Topics include the new methodologies and synergisms being developed in the fields of nanotechnology, pharmaceutical industry, and chemical industry. The symposium featured several researchers including Timor Baasov, Ann-Shyn Chiang, and Chi-Huey Wong.

The article discusses the developments of the scientific periodical "Israel Journal of Chemistry." It discusses the history of the journal's growth and developments since 1949 to 2009 stating the variety of papers presented in the volumes 1 to 4 including biology, chemistry, and geology. It provides information on the new editorial board and inclusion of International Advisory Board for its international avatar.

Information about several papers discussed at the Burgenstock Conference 2010 on the branch of stereochemistry is presented. Recent developments in hydrogen bond-promoted asymmetric catalysis brought opportunities in organic synthesis. The conference featured several researchers including Herbert Mayr, G.K. Surya Prakash, and Viresh H. Rawal.

Selenoenzymes have a central role in maintaining cellular redox potential. These enzymes have selenenylsulfide bonds in their active sites that catalyze the reduction of peroxides, sulfoxides, and disulfides. The selenol/disufide exchange reaction is common to all of these enzymes, and the active site redox potential reflects the ratio between the forward and reverse rates of this reaction. The preparation of enzymes containing selenocysteine (Sec) is experimentally challenging. As a result, little is known about the kinetic role of selenols in enzyme active sites, and the redox potential of a selenenylsulfide or diselenide bond in a protein has not been experimentally determined. To fully evaluate the effects of Sec on oxidoreductase redox potential and kinetics, glutaredoxin 3 (Grx3) and all three Sec variants of its conserved 11CXX14C active site were chemically synthesized. Grx3, Grx3(C11U), and Grx3(C14U) exhibited redox potentials of -194, -260, and -275 mV, respectively. The position of redox equilibrium between Grx3(C11UC14U) (-309 mV) and thioredoxin (Trx) (-270 mV) suggests a possible role for diselenide bonds in biological systems. Kinetic analysis is consistent with the hypothesis that the lower redox potentials of the Sec variants result primarily from the greater nucleophilicity of the active site selenium rather than its role as either a leaving group or a ‘central atom’ in the exchange reaction. The 102–104-fold increase in the rate of Trx reduction by the seleno-Grx3 analogues demonstrates that oxidoreductases containing either selenenylsulfide or diselenide bonds can have physiologically compatible redox potentials and enhanced reduction kinetics in comparison with their sulfide counterparts. [ABSTRACT FROM AUTHOR]

The substrate specificity of 4-oxalocrotonate tautomerase (4-OT) is characterized by electrostatic interactions between positively charged arginine (Arg) side chains on the enzyme and the dianionic substrate, 4-oxalocrotonate. To generate specific hydrogen-bonding interactions with a monoanionic substrate analogue, we have introduced a urea functional group into the active site by replacing arginine side chains with isosteric citrulline (Cit) residues. This design was based on the complementarity between the urea functionality of citrulline and the uncharged amide function of the substrate, as opposed to the guanidinium-carboxylate electrostatic interaction between the wild-type enzyme and the natural substrate. Indeed, the synthetic (Arg39Cit)4-OT analogue catalyzed the tautomerization of the non-natural monoamide-monoacid substrate while it was a poor catalyst for the natural diacid substrate. The specificity of (Arg39Cit)4-OT for the monoamide-monoacid substrate relative to that of the diacid substrate was found to be 740-fold greater than that of the wild-type enzyme for tautomerization of the non-natural substrate as compared with the natural one. The role of electrostatic interactions in the tautomerization of the monoamide-monoacid substrate was probed in detail with several other Arg to Cit analogues of this enzyme. This study has demonstrated that chemical manipulation of the functional groups within the active site of an enzyme can modify its catalytic activity and substrate specificity in a predictable way, suggesting that the incorporation of noncoded amino acids into proteins has great promise for the development of new enzymatic mechanisms and new binding interactions. [ABSTRACT FROM AUTHOR]

Reports on the extensive use of the native chemical ligation reaction for the synthesis of the large polypeptides that correspond to folded proteins and domains. Dependence of the efficiency of the synthesis of the target protein on the number of peptide segments in the synthesis; Need for repeated purification and lyophilization steps.

Presents an antibody-metalloporphyrin assembly that catalyzes the enantioselective oxidation of aromatic sulfides to sulfoxides. Extraction of antibody SN37.4 against water-soluble tin porphyrin; Enzyme characteristics; Enantioselective delivery of oxygen to the substrate; Michaelis-Menten saturation kinetics.

Presents a chemistry laboratory project that provides students with training on biocatalysis and related aspects in organic synthesis, mechanistic organic chemistry and chemical kinetics. Synthesis of aldehyde substrate and racemic aldol product; Titration of the antibody active sites; Analysis of kinetics of the antibody-catalyzed reaction.

Examines the advantages of the `naked carbon skeleton' approach in the total synthesis of polyoxeganted natural products. Synthesis of the 18-membered lichen macrolide, (+)-aspicilin; Comparison of the `naked carbon skeleton' strategy and the bioorganic approach; Reaction mechanisms; Sequence of events in the synthetic design; Alternative pathways.