Reversibly Photoswitchable Fluorescent Diarylethenes Resistant against Photobleaching in Aqueous Solutions
摘要:
Low photostability in aqueous solutions is the main drawback of synthetic photochromic dyes, which limits their switching performance and utility in biology, medicine, and life sciences. Even the most promising photochromes-reversibly photoswitchable diarylethenes (DAEs) with fluorescent "closed" forms-are known to undergo only several tens (typically 20-30) of switching cycles in aqueous solutions. In this work, we introduce water-soluble and highly photostable 1,2-[bis(2-ethyl/2-isobutyl-1-benzothiophene-1,1-dioxide-6-phenyl-3-yl)]perfluorocyclopentenes decorated with four -CONHC(CH2R)(3) residues capped with 12 carboxylic acid groups (R = CH2CO2H, O(CH2)(2)CO2H). Under irradiation with UV (365 nm) and visible light (470 nm), they provide several hundred (for the "rapid" DAEs with isobutyl groups, up to 1000) full switching cycles in aqueous solutions without exclusion of air oxygen (outperforming the photoswitchable and fluorescent protein Dreiklang). The new branching approach based on secondary carboxamides with N-tert-alkyl residues decorated with polar groups may serve as a blueprint for the design of highly fatigue resistant and reversibly photoswitchable fluorescent probes applicable in life sciences as aqueous solutions.
Stereospecific Palladium‐Catalyzed Acylation of Enantioenriched Alkylcarbastannatranes: A General Alternative to Asymmetric Enolate Reactions
作者:Chao‐Yuan Wang、Glenn Ralph、Joseph Derosa、Mark R. Biscoe
DOI:10.1002/anie.201609930
日期:2017.1.16
We report the development of a Pd‐catalyzed process for the crosscoupling of unactivated primary, secondary, and tertiary alkylcarbastannatrane nucleophiles with acyl electrophiles. Reactions involving optically active alkylcarbastannatranes occur with exceptional stereofidelity and with net retention of absolute configuration. Because the stereochemistry of the resulting products is entirely reagent‐controlled
Disclosed is an isomer, enantiomer, diastereoisomer or tautomer of a compound represented by Formula I:
or a salt thereof, in which R
1
, R
2
, R
100
, R
200
, A, A
1
, B, B
1
, BG, n, Q and Q
1
are substituents described. Also disclosed is the use of compounds of Formula 1 to treat proliferative disorders.
A class of pyrazole derivatives is described for use in treating p38 kinase medicated disorders. Compounds of particular interest are defined by Formula IA
wherein R
1
, R
2
, R
3
and R
4
are as described in the specification.
ISOSORBIDE DERIVATIVES AND THEIR USE AS FLAVOR MODIFIERS, TASTANTS, AND TASTE ENHANCERS
申请人:TACHDJIAN Catherine
公开号:US20130295261A1
公开(公告)日:2013-11-07
The present invention provides isosorbide derivatives having the formula shown below and certain subgenera or species thereof, as flavor or taste modifiers, particularly, savory (“umami”) taste modifiers, savory flavoring agents and savory flavor enhancers in foods, beverages, and other comestible compositions,
Pyrazolopyrimidine derivatives as BTK inhibitors for the treatment of cancer
申请人:Loxo Oncology, Inc.
公开号:US10399990B2
公开(公告)日:2019-09-03
This invention relates to novel compounds. The compounds of the invention are tyrosine kinase inhibitors. Specifically, the compounds of the invention are useful as inhibitors of Bruton's tyrosine kinase (BTK). The invention also contemplates the use of the compounds for treating conditions treatable by the inhibition of Bruton's tyrosine kinase, for example cancer, lymphoma, leukemia and immunological diseases.