Ti-direct, powerful, stereoselective aldol-type additions of esters and thioesters to carbonyl compounds: application to the synthesis and evaluation of lactone analogs of jasmone perfumes
thiophenyl esters or thioaryl esters with aldehydes and ketones was performed (total 46 examples). The present method is advantageous from atom-economical and cost-effective viewpoints; good to excellent yields, moderate to good syn-selectivity, substrate variations, reagent availability, and simple procedures. Utilizing the present reaction as the key step, an efficient short synthesis of three lactone
The first example of a palladium-catalyzed aerobic oxidative coupling of acyl chlorides with arylboronic acids has been developed, leading to a wide range of aryl benzoates in good to excellent yields. This catalytic system shows broad functional group tolerance. Preliminary mechanistic experiments using deuterium labeling showed that the oxygen atom was derived from dioxygen.
An efficient TiCl4/amine-promoted aldol-type addition of phenyl and phenylthio esters with aldehydes or ketones has been performed. The present method includes a practical merit from the green chemical viewpoint with regard to yields, variations of substrates, availability of reagents, and simple operations.
Derivates of Polyethylene Glycol Modified Thymosin Alpha 1
申请人:Zhong Huijuan
公开号:US20100184653A1
公开(公告)日:2010-07-22
Pharmaceutical compositions that include thymosin alpha 1 peptide derivatives modified at the C-terminal of the peptide chain with polyethylene glycol, and their pharmaceutical acceptable salts, are generally disclosed. Also, new methods used to prepare these thymosin alpha 1 peptide derivatives modified at the C-terminal of the peptide chain with polyethylene glycol are generally provided. The presently disclosed compounds and their salts can be prepared administered to humans to treat immune disease and can also be used in adjuvant treatment.
Direct C–C Bond Formation from Alkanes Using Ni-Photoredox Catalysis
作者:Laura K. G. Ackerman、Jesus I. Martinez Alvarado、Abigail G. Doyle
DOI:10.1021/jacs.8b09191
日期:2018.10.31
C(sp3)-H bonds and chloroformates has been accomplished via nickel and photoredox catalysis. A diverse range of feedstock chemicals, such as (a)cyclic alkanes and toluenes, along with late-stage intermediates, undergo intermolecular C-C bond formation to afford esters under mild conditions using only 3 equiv of the C-H partner. Site selectivity is predictable according to bond strength and polarity