尽管它们释放相同的芳族糖苷配基,但是两个异构的芳基2-脱氧-2-氟-β-葡糖苷与β-葡糖苷酶的反应速率相差10 6倍。相反,当量的糖苷底物以基本相同的速率常数反应。通过对这些相同底物的非酶促(自发)水解的全面研究,洞悉了这些令人惊讶的速率差异的来源,其中测量了速率的大约10 5倍差异,从而阐明了差异是固有的,而不是原因造成的。与酶的特定相互作用。通过18排除了另一种亲核芳基取代机制导致更快的底物快速反应的可能性O标签研究。对这些速率差异的起源的进一步探索涉及X射线晶体结构的分析以及量子化学计算,这出乎意料地表明,基态去稳定化和过渡态稳定化作用几乎同等地促进了所观察到的反应性差异。这些研究突显了使用简单的参考平衡(例如p K a值)作为离开小组能力的量度的危险。
Water-Soluble, Donor-Acceptor Biphenyl Derivatives in the 2-(o-Nitrophenyl)propyl Series: Highly Efficient Two-Photon Uncaging of the Neurotransmitter γ-Aminobutyric Acid at λ=800 nm
作者:Loïc Donato、Alexandre Mourot、Christopher M. Davenport、Cyril Herbivo、David Warther、Jérémie Léonard、Frédéric Bolze、Jean-François Nicoud、Richard H. Kramer、Maurice Goeldner、Alexandre Specht
DOI:10.1002/anie.201106559
日期:2012.2.20
Rattling the cage: The two γ‐aminobutyric acid (GABA) derivatives 1 and 2 exhibit efficient and rapid (<5×10−6 s) GABA photorelease upon one‐photon excitation combined with two‐photon uncaging cross‐section at λ=800nm. Compounds 1 and 2 were successfully used for two‐photon GABA release in intact brain tissue, thus offering attractive perspectives in chemical neurosciences.
Total synthesis and photophysical properties of PENB-DDAO, a photoactivatable 1,3-dichloro-9,9-dimethyl-9H-acridin-2(7)-one (DDAO) derivative of a far-red emitting fluorophore, are described. The photoremovable group of the DDAO phenolic function comprises a donor/acceptor biphenyl platform which allows an efficient (>= 95%) and rapid (<15 mu s time-range) release of the fluorescent signal and displays remarkable two-photon uncaging cross sections (delta(a).Phi(u) = 3.7 GM at 740 nm). PENB-DDAO is cell permeable as demonstrated by the triggering of cytoplasmic red fluorescent signal in HeLa cells after one-photon irradiation (lambda(exc) around 360 nm) or by the generation of a red fluorescent signal in a delineated area of a single cell after two-photon photoactivation (lambda(exc) = 770 nm).
IMMUNORESPONSIVE METHODS OF TREATING TUMORS
申请人:Batthyany, Carlos
公开号:EP3618830A1
公开(公告)日:2020-03-11
Fluorescent Dye Compounds, Conjugates and Uses Thereof
申请人:Graham Ronald J.
公开号:US20090093062A1
公开(公告)日:2009-04-09
The present teachings generally relate to fluorescent dyes, linkable forms of fluorescent dyes, energy transfer dyes, reagents labeled with fluorescent dyes and uses thereof.