Refernces
10.1002/cplu.201100080
The research focuses on the development of scaffold-optimized dendrimers for the detection of the explosive triacetone triperoxide (TATP) using quartz crystal microbalances (QCM). The purpose of this study is to enhance the sensitivity and selectivity of TATP detection, addressing the limitations of existing methods that rely on the analysis of H2O2 after hydrolysis or dissociation of TATP, which are time-consuming and not suitable for low-cost sensor technology. The researchers synthesized a series of polyphenylene dendrimers with various substituents at the internal branches, aiming to improve the affinity and selectivity for TATP. The chemicals used in the process include triacetone triperoxide (TATP) itself, polyphenylene dendrimers with different functional groups such as pyrenyl, pyridyl, nitro, cyano, and amide moieties, as well as tetraphenylcyclopentadienone and other reagents involved in the synthesis of the dendrimers. The conclusions drawn from the study indicate that the novel polyphenylene-type dendrimers, particularly those containing pyrenyl and cyanophenyl units, not only significantly enhanced the affinity to TATP but also improved selectivity over interfering compounds, allowing for exquisite discrimination of TATP. The study identified compound 5, a nonpolar and pyrenyl-containing dendrimer, as the most promising candidate for TATP sensor applications due to its superior overall characteristics in detection.
10.1016/j.tet.2011.04.099
The study describes a concise and efficient enantioselective synthesis of the 16-membered trilactone macrolides, macrosphelides A and E, from (S)-lactic acid. The synthesis features the use of a previously unexplored ?-ketophosphonate derived from lactic acid and the Yamaguchi lactonization method. The study begins with the addition of a lithium anion to ethyl (S)-trityloxy lactate to form the ?-ketophosphonate, which is then reacted with allylglyoxalate to produce a,?-unsaturated esters. Reduction of these esters yields diastereomeric alcohols, which are subsequently transformed into the required acid and alcohol fragments through protection, saponification, and coupling reactions. The final macro trilactone is obtained via esterification, deprotection, and lactonization steps, yielding macrosphelides A and E with high purity. The overall yield of the synthesis is approximately 19%, and the spectral data of the synthesized compounds match those of the natural products. The procedure is operationally simple and high-yielding, making it suitable for the synthesis of various analogues for potential anti-cancer drug development.
10.1039/b000269k
The research focuses on the preparation of chiral enantiopure 2-(hydroxyalkyl)pyridine derivatives, which are valuable in asymmetric catalysis. The experiments utilize naturally occurring chiral compounds such as D-mannitol, L-lactic acid, and L-mandelic acid as starting materials. Key reactants include 2-lithiopyridine, (R)-2,3-O-isopropylideneglyceraldehyde, and various esters derived from the aforementioned chiral compounds. The methodology involves the synthesis of 2-(1-hydroxyalkyl)pyridines and 6,6'-bis(1-hydroxyalkyl)-2,2'-bipyridines through a series of reactions, including lithiation, reduction with sodium borohydride, and nickel-catalyzed coupling. The analyses used to determine the success of the syntheses and the structures of the products encompass NMR spectroscopy (both 1H and 13C), optical rotation measurements, and in some cases, the preparation and analysis of Mosher's esters to determine the absolute configurations of the synthesized chiral alcohols.
Xi,
C
