Structure–Activity Relationships of Potent, Targeted Covalent Inhibitors That Abolish Both the Transamidation and GTP Binding Activities of Human Tissue Transglutaminase
摘要:
Human tissue transglutaminase (hTG2) is a multifunctional enzyme. It is primarily known for its calcium dependent transamidation activity that leads to formation of an isopeptide bond between glutamine and lysine residues found on the surface of proteins, but it is also a GTP binding protein. Overexpression and unregulated hTG2 activity have been associated with numerous human diseases, including cancer stem cell survival and metastatic phenotype. Herein, we present a series of targeted covalent inhibitors (TCIs) based on our previously reported Cbz-Lys scaffold. From this structure activity relationship (SAR) study, novel irreversible inhibitors were identified that block the transamidation activity of hTG2 and allosterically abolish its GTP binding ability with a high degree of selectivity and efficiency (k(inact)/K-I > 10(5) M-1 min(-1)). One optimized inhibitor (VA4) was also shown to inhibit epidermal cancer stem cell invasion with an EC50 of 3.9 mu M, representing a significant improvement over our previously reported "hit" NC9.
Selective and potent Type-A CCK receptor agonists of formula (I): X--Y--Z--Q (I) or a pharmaceutically acceptable salt thereof, wherein, X is selected from ##STR1## Y is selected from ##STR2## Z is ##STR3## and Q is ##STR4## or pharmaceutically-acceptable salts thereof, useful in the treatment of gastrointestinal disorders (including gallbladder disorders), central nervous system disorders, insulin-related disorders and pain, as well as in appetite regulation.
<i>N</i>-Heterocyclic carbene (NHC) catalyzed amidation of aldehydes with amines <i>via</i> the tandem <i>N</i>-hydroxysuccinimide ester formation
作者:Ashmita Singh、A. K. Narula
DOI:10.1039/d1nj00591j
日期:——
A facile method for the amidation of aldehydes by a cascade approach was developed. This methodology, reported for the first time, uses a N-heterocycliccarbene (NHC) as the catalyst, and N-hydroxysuccinimide (NHS) mediated synthesis of amides utilising TBHP as the oxidant. Various substituted aldehydes reacted smoothly with NHS giving the corresponding active esters in moderate to good yields, which
A photoinduced cross-dehydrogenative-coupling (CDC) reaction between aldehydes and <i>N</i>-hydroxyimides by a TiO<sub>2</sub>–Co ascorbic acid nanohybrid under visible light irradiation
In this study, we performed a visible light-mediated aerobic photo-cross dehydrogenative coupling (CDC) reaction between aldehydes and N-hydroxyimides using TiO2–AA–Co as a photocatalyst for the synthesis of active esters. The synergistic and selective effects of the cobalt ascorbic acid complex (Co–AA) and TiO2 nanoparticles on the visible-light photocatalytic activity were explored. The method possesses
Organocatalytic Amidation and Esterification of Aldehydes with Activating Reagents by a Cross-Coupling Strategy
作者:Bin Tan、Narihiro Toda、Carlos F. Barbas
DOI:10.1002/anie.201205921
日期:2012.12.7
Formation on demand: An organocatalytic cross‐coupling reaction of aldehydes with N‐hydroxyimides, hexafluoroisopropyl alcohol, and sulfonimides has been developed. The resulting active intermediates can be directly converted into amides or esters in one pot. This simple method makes use of readily available starting materials, and the newly discovered activatingreagents should find broad application
Convenient Synthesis of <i>N</i>-Hydroxysuccinimide Esters from Carboxylic Acids Using Triphosgene
作者:Misoo Kim、Ki-Jong Han
DOI:10.1080/00397910902906628
日期:2009.11.18
Abstract A simple and convenientmethod for the synthesis of N-hydroxysuccinimide ester is developed using triphosgene as an acid activator. Several aromatic and aliphatic N-hydroxysuccinimide esters are prepared from their corresponding carboxylic acids at room temperature in good yields in a rapid process using triphosgene. Some of the major advantages are mild conditions, good yields, and easy operation