Resourceful synthesis of pyrazolo[1,5-a]pyrimidines under ultrasound irradiation
摘要:
Pyrazolo[1,5-a]pyrimidines were synthesized via the ultrasonic sonochemical method using the cyclo-condensation reaction of 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones [CF3(C)(O)CH = C(R)(OMe) - where R = Me, Bu, i-Bu, Ph, 4-Me-C6H4, 4-F-C6H4, 4-CI-C6H4, 4-Br-C6H4, naphth-2-yl and biphen-4-yl] - with 3-amino-5-methyl-1H-pyrazole in the presence of EtOH for 5 min. This methodology has several advantages, for example, it is a simple procedure, it has an easy work-up, Mild conditions, short reaction times (5 min) and produces satisfactory yields (61-98%). (C) 2013 Elsevier B.V. All rights reserved.
Reactivity of electrogenerated thiocyanogen in the thiocyanation of pyrazolo[1,5-a]pyrimidines
作者:Vladimir A. Kokorekin、Rauza R. Yaubasarova、Sergei V. Neverov、Vladimir A. Petrosyan
DOI:10.1016/j.mencom.2016.09.016
日期:2016.9
Selective thiocyanation (yield 70–90%) at the 3-position of pyrazolo[1,5- a ]pyrimidines was performed with thiocyanogen electrochemically generated in situ from NH 4 SCN in MeCN on a Pt anode. For substrates with higher oxidation potential addition of Lewis acids was necessary.
Electrooxidative C-H Functionalization of Heteroarenes. Thiocyanation of Pyrazolo[1,5-<i>a</i>
]pyrimidines
作者:Vladimir A. Kokorekin、Rauza R. Yaubasarova、Sergei V. Neverov、Vladimir A. Petrosyan
DOI:10.1002/ejoc.201900390
日期:2019.7.14
An effective system of approaches to electrooxidative C–H thiocyanation of both high and low reactive pyrazolo[1,5‐a]pyrimidines under mild conditions has been proposed for the first time. The process scaling up, the antifungal activity of resulting thiocyanates, and possibility of their transformation into thiols also demonstrate advantages and viability of this direct C–S coupling strategy. In general
首次提出了在温和条件下有效反应高和低反应性吡唑并[1,5- a ]嘧啶的C–H硫氰化方法的有效体系。规模扩大的过程,所得硫氰酸盐的抗真菌活性以及将其转化为硫醇的可能性也证明了这种直接C-S偶联策略的优势和可行性。通常,温和的反应条件和高的C–S键形成效率使这种基于吡唑并[1,5- a ]嘧啶的电氧化C–H硫氰化的策略在未来的应用中非常可行。
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作者:V. I. Filyakova、O. A. Kuznetsova、E. N. Ulomskii、T. V. Rybalova、Yu. V. Gatilov、M. I. Kodess、V. L. Rusinov、K. I. Pashkevich
DOI:10.1023/a:1015420130033
日期:——
The reactions of Li enolates of fluorine-containing beta-diketones with 3-aminopyrazoles afforded (7-polyfluoroalkyl)pyrazolo[1,5-a]pyrimidines. The structure of 3-bromo-2-methyl-5-phenyl-7-trifluoromethylpyrazolo[1,5-a]pyrimidine was established by X-ray diffraction analysis.
REPORTER SYSTEM FOR HIGH THROUGHPUT SCREENING OF COMPOUNDS AND USES THEREOF
申请人:RATAN Rajiv
公开号:US20130005666A1
公开(公告)日:2013-01-03
The NF-E2-related factor 2 (Nrf2) is a key transcriptional regulator of antioxidant defense and detoxification. To directly monitor stabilization of Nrf2 we fused its Neh2 domain, responsible for the interaction with its nucleocytoplasmic regulator, Keap1, to firefly luciferase (Neh2-luciferase). It is shown herein that Neh2 domain is sufficient for recognition, ubiquitination and proteasomal degradation of Neh2-luciferase fusion protein. The novel Neh2-luc reporter system allows direct monitoring of the adaptive response to redox stress and classification of drugs based on the time-course of reporter activation. The novel reporter was used to screen a library of compounds to identify activators of Nrf2. The most robust and yet non toxic Nrf2 activators found—nordihydroguaiaretic acid, fisetin, and gedunin-induced astrocyte-dependent neuroprotection from oxidative stress via an Nrf2-dependent mechanism.