A series of analogues of the selective non-peptide urotensin II (UII) receptor agonist 3-(4-chlorophenyl)-3-(2-dimethylaminoethyl)-isochroman- 1-one (AC-7954, 1) was synthesized and evaluated for UII agonist activity using a functional cell-based assay. The introduction of a methyl group in the 4-position resulted in a complete loss of activity, whereas substituents in the aromatic rings were beneficial. Sterically demanding amino groups were also detrimental to the activity. Several potent agonists were identified, six compounds being equally or more potent than 1. The most potent compound in the series was the 6,7-dimethyl analogue of 1 (16, pEC(50) 6.87). The racemate of 16 was resolved into the pure enantiomers using preparative straight phase HPLC. It was shown that the potency resides in the (+)-enantiomer (pEC(50) 7.11). The synthesized compounds seem to be selective for the UII receptor as no activities were observed at the closely related SSTR3 and 5 receptors. (c) 2005 Elsevier Ltd. All rights reserved.
Sur la synthèse du dibenzo[a,i]pyrène, du tribenzo[a,e,i]pyrène, et de nouveaux homologues du naphto[2,3-a]pyrène
作者:N.P. Buu-Hoï、Denise Lavit
DOI:10.1016/s0040-4020(01)93323-x
日期:1960.1
The synthesis of dibenzo[a,i]pyrene is reported, starting from benzo[a]pyrene, obtained by condensation of succinic anhydride in position 1, followed by reduction of the resulting keto acid to γ-1-benzo[a]pyrenylbutyric acid, and cyclisation to 4-keto-1:2:3:4-tetrahydrodibenzo[a,i]pyrene; the latter ketone was reduced to 1:2:3:4-tetrahydrodibenzo[a,i]pyrene, which was then dehydrogenated. Further,
A preparation, comprising a mixture of dibenzoyl peroxides where the mixture of dibenzoyl peroxides contains 50 to 99.7 mole % of a symmetric dibenzoyl peroxide and 0.3 to 50 mole % asymmetric dibenzoyl peroxides, shows a reduced decomposition temperature of the peroxides compared to the symmetric dibenzoyl peroxide and is suitable for hot cross-linking silicone rubber. The preparation can be produced by reacting a mixture containing a first benzoyl chloride and a second benzoyl chloride that is different therefrom with hydrogen peroxide, wherein the mixture of benzoyl chlorides contains 70 to 99.7 mole % of the first benzoyl chloride and 0.3 to 30 mole % of the second benzoyl chloride.
6-dipivaloyl-1,2,4,5-tetramethylbenzene were prepared by the Friedel-Grafts dipropionylation of the corresponding polymethylbenzenes, followed by the exhaustivemethylation of the resulting diketones with potassium t-butoxide and methyl iodide in boiling benzene-t-butyl alcohol. The PMR and IR spectra are reported for these new compounds.
2,4-二新戊酰基-1,3,5-三甲基苯、4,6-二新戊酰基-1,2,3,5-四甲基苯和 3,6-二新戊酰基-1,2,4,5-四甲基苯的制备方法如下:相应的多甲基苯的 Friedel-Grafts 二丙酰化,然后在沸腾的苯 - 叔丁醇中用叔丁醇钾和甲基碘彻底甲基化得到的二酮。报告了这些新化合物的 PMR 和 IR 光谱。
Photocarboxylation of remote C–H bonds through nitrogen-centred radical 1,5-hydrogen atom transfer
作者:Wenke Li、Beiqi Sun、Lei Zhang、Fanyang Mo
DOI:10.1039/d3gc01426f
日期:——
carboxylation of the C–H bond utilizing CO2 represents a challenging but attractive tactic for capitalizing on the abundant availability of CO2 in organic synthesis. In this investigation, we report visible-light-driven carboxylation of a remoteC–H bond via a nitrogen-centered 1,5-hydrogen atom transfer (1,5-HAT) mechanism. The achievement of direct photocarboxylation of the remote benzylic C–H bond has been
Visible-Light-Induced Transition-Metal-Free Redox-Neutral Carboxylation of Remote Benzylic C(sp<sup>3</sup>)–H Bonds via 1,5-Hydrogen Atom Transfer
作者:Wenke Li、Beiqi Sun、Lei Zhang、Fanyang Mo
DOI:10.1021/acs.joc.3c02250
日期:2024.1.5
The direct carboxylation of the benzylic C–H bonds under mild conditions is of great importance and is quite challenging. Herein, we report an approach for the carboxylation of remote benzylic C(sp3)–H bonds by integrating the redox-neutral visible-light photoredox catalysis and the nitrogen-centered 1,5-hydrogen atom transfer. The chemical transformation progresses via consecutive single electron