نتایج جستجو برای: ugi four component
تعداد نتایج: 1200492 فیلتر نتایج به سال:
This review describes the recent advances in the microwave-assisted synthesis of 7-membered and larger heterocyclic compounds. Several types of reaction for the cyclization step are discussed: Ring Closing Metathesis (RCM), Heck and Sonogashira reactions, Suzuki-Miyaura cross-coupling, dipolar cycloadditions, multi-component reactions (Ugi, Passerini), etc. Green syntheses and solvent-free proc...
The fast pace of drug discovery programs, aided by highthroughput screening campaigns, often relies on the generation of combinatorial libraries to identify new chemical entities. The Ugi 4and 3-component reactions in particular [1], have proven to be robust in producing both tool compounds and drugs [2,3]. Here we report a high-throughput entry into the imidazopyridine scaffold, using a microf...
A solution phase synthesis of peptide nucleic acid monomers and dimers was developed by using microwave-promoted Ugi multicomponent reactions. A mixture of a functionalized amine, a carboxymethyl nucleobase, paraformaldehyde and an isocyanide as building blocks generates PNA monomers which are then partially deprotected and used in a second Ugi 4CC reaction, leading to PNA dimers. Conformationa...
A practical three-step protocol for the assembly of triazolobenzodiazepine-fused diketopiperazines and hydantoins has been developed. The synthesis of these tetracyclic ring systems was initiated by an Ugi reaction, which brought together all necessary functionalities for further transformations. The Ugi adducts were then subjected to a base-induced ring closing and an intramolecular azide-alky...
Background and Objective: To assess the incidence and risk factors of upper gastrointestinal bleeding in children admitted to pediatric intensive care unit for more than 6 hrs. Methods: We prospectively collected medical records of children between 1 month and 18 years old admit-ted to our 10 bed PICU of a tertiary care university hospital between December 1, 2014 and May 30, 2015. De-mographi...
A focused library of virtual heterobifunctional ligands was generated in silico and a set of ligands with recombined fragments was synthesized and evaluated for binding to Clostridium difficile toxins. The position of the trisaccharide fragment was used as a reference for filtering docked poses during virtual screening to match the trisaccharide ligand in a crystal structure. The peptoid, a div...
An alternative approach toward the simple and robust synthesis of highly substituted peptidic thiazole derivatives using Ugi-multicomponent reaction (U-MCR) is described. Thus, we introduced the enantiopure (R)-2-methyl-2-isocyano-3-(tritylthio)propanoate as a novel class of isocyanide in MCR. This bifunctional isocyanide was found to undergo mild cyclodehydration to afford thiazole containing ...
The first chiral catalyst for the three-component Ugi reaction was identified as a result of a screen of a large set of different BOROX catalysts. The BOROX catalysts were assembled in situ from a chiral biaryl ligand, an amine, water, BH3·SMe2, and an alcohol or phenol. The catalyst screen included 13 different ligands, 12 amines, and 47 alcohols or phenols. The optimal catalyst system (LAP 8-...
Chlorination-elimination chemistry coupled with three-component Joullié-Ugi reaction and facile deprotection allowed efficient access to an array of polyhydroxylated pyrrolidines through parallel synthesis that may be considered to be a library of imino (aza) sugars (glycomimetics) and/or dihydroxyprolyl peptides (peptidomimetics). The utility of generating such a library was illustrated by scr...
A series of new fluorene bisamide derivatives were synthesized through multi-component Ugi reaction and tested for their in vitro anti-mycobacterial activity. The structures of the products 5a-w were deduced from their IR, 1H NMR, and 13C NMR spectra. Elemental analyses (CHN) for novel compounds (5a, 5d, 5f, 5h, 5k, 5l, 5p, 5s, 5t, 5v, 5w) was done to. These compounds were evaluated as anti-bac...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید