10.1016/j.tetasy.2008.04.016
The study presents the first synthesis of a 12-membered macrolide natural product, determining its absolute stereochemistry through a ring-closing metathesis (RCM) protocol. The synthesis involved key steps such as syn-selective reduction, Yamaguchi esterification, and RCM. Chemicals used included 1,4-butane diol, Swern's reagent, Barbier reagents, benzyl bromide, and Grubbs' catalyst, among others. These chemicals served various purposes in the synthesis process, such as protecting groups, reagents for oxidation and reduction reactions, and catalysts for the RCM step. The synthesized compounds were characterized by their physical and spectroscopic data, which were compared to the reported values of the natural product to confirm the synthesis and determine the correct absolute stereochemistry.
10.1002/adfm.201103147
The research focuses on the development of a new family of cationic charged biocompatible hybrid hydrogels, based on arginine unsaturated poly(ester amide) (Arg-UPEA) and Pluronic diacrylate (Pluronic-DA), which were fabricated through UV photocrosslinking in an aqueous medium. The purpose of this study was to improve the cellular interactions of synthetic hydrogels for potential biomedical applications by introducing cationic Arg-UPEA, which possesses biocompatibility and cationic properties. The conclusions drawn from the research indicate that the incorporation of Arg-UPEA into Pluronic-DA hydrogels significantly enhanced cell attachment, proliferation, and viability of both Detroit 539 human fibroblasts and bovine aortic endothelial cells. The chemicals used in the process include Pluronic F127, acryloyl chloride, triethylamine, Irgacure 2959 (as a photoinitiator), L-arginine, p-toluenesulfonic acid monohydrate, fumaryl chloride, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, and p-nitrophenol, among others. These chemicals were utilized in the synthesis of the hydrogel precursors and for the characterization of their physicochemical properties.
10.1021/ol9015755
The study presents the second total synthesis of Brevisamide, a marine cyclic ether alkaloid derived from Karenia brevis. The streamlined synthesis was achieved in 21 steps with a 5.2% overall yield, featuring a key SmI2 reductive cyclization step to access the tetrasubstituted pyran core. Key chemicals used in the study include monobenzyl protected-1,4-butane diol, which served as the starting material for the synthesis of pyran 3; ethyl propiolate, used in the 1,4-addition to form intermediate 9; and phosphonate ester 2, synthesized through a series of reactions including a Wittig reaction and an Arbuzov reaction, which was crucial for the Horner-Wadsworth-Emmons reaction to assemble the western C1-C4 and eastern C5-C15 fragments. The purpose of these chemicals was to construct the complex structure of Brevisamide through a series of strategic synthetic steps, ultimately leading to the successful synthesis of the natural product.
10.1021/jo0057194
The research describes the enantioselective synthesis of various marine natural products using enantiomerically enriched hydroxy-γ-lactones as key intermediates. The purpose of this study is to develop a general methodology for the synthesis of both linear and cyclic marine natural products, focusing on compounds with a highly functionalized tetrahydrofuran ring and their linear biogenetic precursors. The researchers utilized Sharpless asymmetric dihydroxylation (AD) and Katsuki-Sharpless asymmetric epoxidation (AE) as enantioselective reactions to achieve high enantiomeric purity in the final products. Key chemicals used in the research include butane-1,4-diol, malonic acid, piperidine, AD-mix-α and AD-mix-β for asymmetric dihydroxylation, and (R,R)-(+)-DET and (S,S)-(-)-DET for asymmetric epoxidation. The study concludes that the described methodology provides a versatile and efficient route for the synthesis of marine natural products, ensuring high enantiomeric purity and yielding compounds such as trans-(+)-laurediol, (2S,3S,5R)-5-[(1R)-1-hydroxy-9-decenyl]-2-pentyltetrahydro-3-furanol, and (2S,3S,5S)-5-[(1S)-1-hydroxy-9-decenyl]-2-pentyltetrahydro-3-furanol.
10.1055/s-0029-1217556
The study investigates the influence of protecting groups at C4 and C7 on a ring-closing metathesis reaction to achieve the total synthesis of stagonolide C and the formal total synthesis of modiolide A. The key chemicals involved include L-malic acid and butane-1,4-diol as starting materials. Sharpless asymmetric epoxidation, activated zinc dust mediated reductive elimination, and ring-closing metathesis are the crucial reactions. The protecting groups, such as p-methoxybenzyl ethers and TBS ethers, play significant roles in controlling the geometry of the newly formed double bond during the ring-closing metathesis reaction. The successful synthesis of stagonolide C and modiolide A demonstrates the effectiveness of the selected protecting groups and the chosen synthetic strategy.
Xn
Xn:Harmful;
