N-Alkynyl Imides (Ynimides): Synthesis and Use as a Variant of Highly Labile Ethynamine
摘要:
This study describes the first reliable synthesis of N-alkynyl imides (ynimides). This was accomplished with a copper-catalyzed coupling reaction between alkynyl(triaryl)bismuthonium salts and five-membered imides. We also found that it was possible to utilize N-ethynyl phthalimide as a variant of the highly labile ethynamine. 4-Amino-1,2,3-triazole was successfully obtained via the CuAAC reaction of N-ethynyl phthalimide with azide followed by hydrazinolysis of the phthaloyl protecting group.
and electronic properties that partially mirror those of ureas, therefore demonstrating that the hydrofluorination of ynamides provides a general, straightforward, and user-friendly approach to bioisosteres of ureas, potent building blocks for biological studies and medicinal chemistry.
Copper-Catalyzed Tandem Decyclization-Cyclization Reaction of <i>N</i>-Alkynyl-3-hydroxyisoindolin-1-ones Generated from <i>N</i>-Alkynyl Phthalimides: Selective Synthesis of <i>ortho</i>-(2-Oxazolyl)phenyl Ketones
作者:Takuya Sueda、Noriko Okamoto、Reiko Yanada
DOI:10.1021/acs.joc.6b00888
日期:2016.7.1
ynamides) as a new subgroup of ynamides. Owing to the alkynyl motif on the nitrogen atom, alpha-hydroxy ynamides were easily isomerized to the corresponding ortho-(2-oxazolyl)phenyl ketones in a CuCl-catalyzed tandem decyclization-cyclization reaction under mild conditions.
Compounds of the formula (I)
or pharmaceutically acceptable salts are described, wherein R1 and R2 are independently hydrogen or C1-6alkyl, or R' and R2 together represent -(CH2)q- wherein q is 4 to 7, to torm together with the nitrogen atom to which they are attached, a 5-8 membered saturated ring, optionally substituted by C1-6alkyl; X is -CH2- or sulphur; n is 2 or 3, or if X is -CH,- n can also be 1; p is 1 or 2; and R' is hydrogen, C1-6alkyl, C3-6 alkenyl or C3-6alkynyl (wherein the unsaturated bond is not adjacent to the -NH- moiety).
The compounds are histamine H2-receptor antagonists and are useful in treating diseases mediated via histamine H2-receptors. Processes for their preparation, pharmaceutical compositions containing them and methods of use are described.
<i>N</i>-Alkynyl Imides (Ynimides): Synthesis and Use as a Variant of Highly Labile Ethynamine
作者:Takuya Sueda、Ayumi Oshima、Naoki Teno
DOI:10.1021/ol2014973
日期:2011.8.5
This study describes the first reliable synthesis of N-alkynyl imides (ynimides). This was accomplished with a copper-catalyzed coupling reaction between alkynyl(triaryl)bismuthonium salts and five-membered imides. We also found that it was possible to utilize N-ethynyl phthalimide as a variant of the highly labile ethynamine. 4-Amino-1,2,3-triazole was successfully obtained via the CuAAC reaction of N-ethynyl phthalimide with azide followed by hydrazinolysis of the phthaloyl protecting group.
Ag- and Au-Catalyzed Addition of Alcohols to Ynimides: β-Regioselective Carbonylation and Production of Oxazoles
Metal-catalyzed reactions of ynimides with alcohols to afford β-ketoimides and oxazoles are demonstrated. The triple bond of ynamides is generally activated by mineral acids or metal salts to lead to the regioselective addition of nucleophiles at the α-C-atom, because of the inherent electronic bias. In contrast, the two neighboring carbonyl groups of ynimides decrease the electron density of the triple