نتایج جستجو برای: ugi reaction
تعداد نتایج: 412882 فیلتر نتایج به سال:
The Ugi four-component reaction (U-4CR) with N-hydroxyimides as a novel carboxylic acid isostere has been reported. This reaction provides straightforward access to α-hydrazino amides. A broad range of aldehydes, amines, isocyanides and N-hydroxyimides were employed to give products in moderate to high yields. This reaction displays N-N bond formation by cyclic imide migration in the Ugi reacti...
Herein we describe a versatile approach for the synthesis of acylhydrazino-peptomers, a new class of peptidomimetics. The key idea in this approach is based on a simple route using a one-pot hydrazino-Ugi four-component reaction followed by a hydrazinolysis or hydrolysis reaction and subsequent hydrazino-Ugi reaction or classical Ugi reaction for the construction of acyclic acylhydrazino-peptom...
The Ugi reaction of 2-substituted dihydrobenzoxazepines was found to proceed with unexpectedly good diastereoselectivitiy (diastereoisomeric ratios up to 9:1), despite the large distance between the pre-existing stereogenic centre and the newly generated one. This result represents the first good 1,4 asymmetric induction in an Ugi reaction as well as the first example of diastereoselective Ugi ...
vilsmeier several diamide derivatives containing 2-chloroquinoline scaffolds were synthesized via ugi reaction of 2-chloroquinoline-3-carboxaldehydes, amines, carboxylic acids and isocyanides. the diversity of these quinolinyl ugi-adducts was increased by using 2-chloroquinoline-3-carboxylic acids as a source of acid. among them, compounds 2d, 2n, 2p, 4a, 4c and 4e displayed moderate to good an...
A general strategy is introduced for the efficient synthetic access of disulfide linked artificial macrocycles via a Ugi four-component reaction (U4CR) followed by oxidative cyclization. The double-mercapto input is proposed for use in the Ugi reaction, thereby yielding all six topologically possible combinations. The protocol is convergent and short and enables the production of novel disulfid...
Vilsmeier Several diamide derivatives containing 2-chloroquinoline scaffolds were synthesized via Ugi reaction of 2-chloroquinoline-3-carboxaldehydes, amines, carboxylic acids and isocyanides. The diversity of these quinolinyl Ugi-adducts was increased by using 2-chloroquinoline-3-carboxylic acids as a source of acid. Among them, compounds 2d, 2n, 2p, 4a, 4c and<strong...
In this study, boron-containing primary amines were synthesized for use as building blocks in the study of peptoids. In the first step, Gabriel synthesis conditions were modified to enable the construction of seven different aminomethylphenyl boronate esters in good to excellent yields. These compounds were further utilized to build peptoid analogs via an Ugi four-component reaction (Ugi-4CR) u...
An efficient Ugi three-component reaction of a preformed chiral ketimine derived from isatin with various isonitrile and acid components has been developed. The reactions proceeded smoothly and in a stereocontrolled manner with regard to the new center of the Ugi products due to the stereoinduction of the amine chiral residue. A wide variety of novel chiral 3,3-disubstituted 3-aminooxindoles we...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید