Substrate Activity Screening: A Fragment-Based Method for the Rapid Identification of Nonpeptidic Protease Inhibitors
作者:Warren J. L. Wood、Andrew W. Patterson、Hiroyuki Tsuruoka、Rishi K. Jain、Jonathan A. Ellman
DOI:10.1021/ja0547230
日期:2005.11.1
A new fragment-basedmethod for the rapid development of novel and distinct classes of nonpeptidic protease inhibitors, SubstrateActivityScreening (SAS), is described. This method consists of three steps: (1) a library of N-acyl aminocoumarins with diverse, low molecular weight N-acyl groups is screened to identify protease substrates using a simple fluorescence-based assay, (2) the identified N-acyl
TBHP/n-Bu4PBr-Promoted Oxidative Cross-Dehydrogenative Coupling of Aryl Methanols: A Facile Synthesis of Symmetrical Carboxylic Anhydride Derivatives
作者:Mehdi Adib、Rahim Pashazadeh
DOI:10.1055/s-0036-1590905
日期:2018.1
A transition-metal-free oxidative cross-dehydrogenativecoupling reaction has been developed for the preparation of symmetrical carboxylic anhydrides through self-coupling dual C–O bond formations of aryl methanols. In the presence of a catalytic amount of tetrabutylphosphonium bromide (TBPB) as transfer agent and aqueous tert-butyl hydroperoxide (TBHP) as oxidant and reactant, methylene groups of
A Versatile, Practical, and Inexpensive Reagent, Pyridine-3-carboxylic Anhydride (3-PCA), for Condensation Reactions
作者:Setsuo Funasaka、Teruaki Mukaiyama
DOI:10.1246/bcsj.81.148
日期:2008.1.15
A highly useful method for the preparation of carboxylic esters and carboxamides from various carboxylic acids was established by using a novel condensing reagent, pyridine-3-carboxylic anhydride (3-PCA), in the presence of 4-(dimethylamino)pyridine as an activator. The reactions of various carboxylic acids with nucleophiles, such as alcohols or amines, afforded the corresponding carboxylic acids or carboxamides in good to high yields under mild conditions by using simple experimental procedure. In addition, it was confirmed that this protocol was applicable to a gram-scale synthesis and the by-products, including pyridine-3-carboxylic acid and pyridine-3-carboxylate (or pyridine-3-carboxamide) produced in situ, were easily removed by using a simple aqueous workup.
Facile and direct synthesis of symmetrical acid anhydrides using a newly prepared powerful and efficient mixed reagent
作者:Hamed Rouhi-Saadabad、Batool Akhlaghinia
DOI:10.1515/chempap-2015-0042
日期:2015.1.1
An efficient mixed reagent for direct synthesis of symmetrical carboxylic anhydrides from carboxylic acids has been prepared. Carboxylic acids are converted to anhydrides using triphenylphosphine/trichloroisocyanuric acid under mild reaction conditions at room temperature. Short reaction time, excellent yields of products, low cost, availability of reagents, simple experimental procedure, and easy
acylation of symmetrical carboxylic anhydrides has inherited limitation of reaction efficiency along with relatively poor reactivity. Traditionally, one equivalent carboxylic acid is generated during nucleophilic acylation of a symmetrical anhydride, which always limits the yield of final product to 50% or less. This is a major drawback, which discourages the use of anhydrides for laboratory or industrial