A new and efficient route to 7-ethyl-1H-furo[2,3-g]indazole (2) has been developed. Treatment of 4,5-dihydro-7-(1-hydroxyethyl)indazole (12) with hydrochloric acid in ethanol resulted in a concomitant dehydration and aromatization to afford the title compound in good yield.
Microwave-assisted synthesis of 4-keto-4,5,6,7-tetrahydrobenzofurans
The use of TMSCI in methanol under microwave irradiation allows the facile intramolecular condensation of a large panel of triketones, giving rise to 4-keto-4,5,6,7-tetrahydrobenzofurans in good to excellent yields. (C) 2008 Elsevier Ltd. All rights reserved.
Synthesis and structure–activity relationships of a series of substituted 2-(1H-furo[2,3-g]indazol-1-yl)ethylamine derivatives as 5-HT2C receptor agonists
A series of novel indazole derivatives were synthesized, and their structure-activity relationships examined in order to identify potent and selective 5-HT2C receptor agonists. Among these compounds, (S)-2-(7-ethyl-1H-furo[2,3-g]indazol-1-yl)-1-methylethylamine (YM348) had a good in vitro profile, that is, high agonistic activity to the human 5-HT2C receptor subtype (EC50 = 1.0 nM) and high selectivity
Mercuric Triflate Catalyzed Cycloisomerization of Alkynyl-1,3-Cyclohexanedione and Alkynyl-1,3-Cyclopentanedione
作者:Mugio Nishizawa、Hiroshi Imagawa、Shuhei Kotani
DOI:10.1055/s-2006-932464
日期:——
Mercuric triflate was used to catalyze cycloisomerization of alkynyl-1,3-cyclohexanediones and cyclopentanediones to give fused oxabicyclic systems under mild reaction conditions with high catalytic turnover up to 1000 times.