Electro-organic Synthesis 68. Diastereoselective Cathodic Reduction of Phenylglyoxylic Acid Attached to Chiral Auxiliaries.
摘要:
Two chiral auxiliaries were attached to phenylglyoxylic acid as amides in 67-70% yield. Cyclic voltammetry of one amide in acetonitrile-pivalic acid (0.117 mol l(-1)) shows that it is irreversibly reduced at --0.73 to -1.07 V (vs. Ag/AgCl) depending on the cation of the supporting electrolyte. During preparative-scale electrolysis the amides afforded the corresponding mandelic acid derivatives in 64-76% yield and 52-86% de, respectively. The diastereoselectivities depend on solvent, proton donor, supporting electrolyte, temperature and the substituent R in the 2-oxo acid amides. The results are in accordance with an ECE-reduction of the Zero acid amide to an enolate anion, which subsequently undergoes a face-selective protonation to the mandelic acid amide.
The present invention provides a compound of the general formula 1,
wherein X is the connection between the CO-hydrazine and the NR1-oxalic acid or ester group, and uses and synthesis methods. These compounds represent amino acid derivatives, wherein the amine group is turned into an acidic group by the oxalic acid group and the carboxylic acid is turned into an amine functionality by the hydrazine group; as well as peptidomimetics comprising the compound and methods for their synthesis.
Synthesis of N-trifluoromethyl amides from carboxylic acids
作者:Jianbo Liu、Matthew F.L. Parker、Sinan Wang、Robert R. Flavell、F. Dean Toste、David M. Wilson
DOI:10.1016/j.chempr.2021.07.005
日期:2021.8
frequently found in pharmaceutical compounds. To date, there is no strategy for synthesizing N-trifluoromethyl amides from abundant organic carboxylicacid derivatives, which are ideal starting materials in amide synthesis. Here, we report the synthesis of N-trifluoromethyl amides fromcarboxylicacid halides and esters under mild conditions via isothiocyanates in the presence of silver fluoride at room temperature
In one aspect, the invention relates to compounds having the formula:
where R
1
-R
6
, a, b, and Z are as defined in the specification, or a pharmaceutically acceptable salt thereof. These compounds have neprilysin inhibition activity. In another aspect, the invention relates to pharmaceutical compositions comprising such compounds; methods of using such compounds; and processes and intermediates for preparing such compounds.
[EN] SUBSTITUTED PYRROLIZINE COMPOUNDS AND USES THEREOF<br/>[FR] COMPOSÉS DE PYRROLIZINE SUBSTITUÉS ET LEURS UTILISATIONS
申请人:GILEAD SCIENCES INC
公开号:WO2018039531A1
公开(公告)日:2018-03-01
This application relates to substituted fused pyrrole compounds of formula I, and pharmaceutical compositions comprising them which inhibit HBV replication, and methods of making and using them. Formula (I)
Enantio- and chemoselective Brønsted-acid/Mg(<sup>n</sup>Bu)<sub>2</sub> catalysed reduction of α-keto esters with catecholborane
作者:Dieter Enders、Bianca A. Stöckel、Andreas Rembiak
DOI:10.1039/c4cc00427b
日期:——
The first enantio- and chemoselective Bronsted-acid catalysed reduction of alpha-keto esters with catecholborane has been developed. The alpha-hydroxy esters were obtained under mild reaction conditions in virtually quantitative yields and excellent enantioselectivities. With slight modifications both enantiomers can be obtained without any loss of selectivity.