Visible-light-promoted radical alkylation/cyclization of allylic amide with N-hydroxyphthalimide ester: Synthesis of oxazolines
作者:Zhiyang Yan、Bin Sun、Panyi Huang、Haiyun Zhao、Hao Ding、Weike Su、Can Jin
DOI:10.1016/j.cclet.2021.09.067
日期:2022.4
An efficient photocatalytic alkylation/cyclization of allylic amide with N-hydroxyphthalimide ester has been developed. The transformation is taken advantage of alkyl radicals to attack allylic amide with the assist of inexpensive rose bengal as photocatalyst to prepare a series of alkyl substituted oxazolines in moderate to excellent yields. High regioselectivity, operational safety, mild conditions
<i>N</i>-Bromoimide/DBU Combination as a New Strategy for Intermolecular Allylic Amination
作者:Ying Wei、Fushun Liang、Xintong Zhang
DOI:10.1021/ol402287n
日期:2013.10.18
Allylic amination reactions of alkenes, with an NBP (N-bromophthalimide) or NBS (N-bromosuccinimide)/DBU combination, were developed, in which both internal and external nitrogen nucleophiles can be installed directly. Dual activation of NBS or NBP by DBU leads to more electrophilic bromine and more nucleophilic nitrogen atoms simultaneously. This protocol may provide a novel and complementary access
Characterization of a Series of 3-Amino-2-phenylpropene Derivatives as Novel Bovine Chromaffin Vesicular Monoamine Transporter Inhibitors
作者:Rohan P. Perera、D. Shyamali Wimalasena、Kandatege Wimalasena
DOI:10.1021/jm030004p
日期:2003.6.1
A series of 3-amino-2-phenylpropene (APP) derivatives have been synthesized and characterized as novel competitive inhibitors, with K-i values in the muM range, for the bovine chromaffin granule membrane monoamine transporter(s) (bVMAT). Although, these inhibitors are structurally similar to the bVMAT substrate tyramine, none of them were measurably transported into the granule. Structure-activity studies have revealed that, while the 3'- or 4'-OH groups on the aromatic ring enhance the inhibition potency, Me or OMe groups in these positions reduce the inhibition potency. Halogen substitution on the 4'-position of the aromatic ring causes gradual increase of the inhibition potency parallel to the electron donor ability of the halogen. Substituents on the NH2 as well as on the 3-position of the alkyl chain reduce the inhibition potency. Comparative structure-activity analyses of APP derivatives with tyramine and the neurotoxin 1-methyl-4-phenylpyridinium suggest that the flexibility of the side chain and the relative orientation of the NH2 group may be critical for the efficient transport of the substrate through the bVMAT. Comparable bVMAT affinities of these inhibitors to that of DA and other pharmacologically active amines suggest that they are suitable for the structure-activity and mechanistic studies of monoamine transporters and may also be useful in modeling the mechanism of action of amphetamine-related derivatives.
Substrate-Directable Heck Reactions with Arenediazonium Salts. The Regio- and Stereoselective Arylation of Allylamine Derivatives and Applications in the Synthesis of Naftifine and Abamines
The palladium-catalyzed, substrate-directable Heck-Matsuda reaction of allylamine derivatives with arenediazonium salts is reported. The reaction proceeds under mild conditions, with excellent regio- and stereochemical control as a function of coordinating groups present in the allylamine substrate. The distance between the olefin moiety and the carbonylic system seems to play a key role regarding the regiocontrol. The method presents itself as robust, as simple to carry out, and with wide synthetic scope concerning the allylic substrates and the type of arenediazonium employed. The synthetic potential of the method is illustrated by the short total syntheses of the bioactive compounds naftifine, abamine, and abamine SG.