synthesis and analysis of some bis-heterocyclic compounds containing sulphur的合成和分析一些bis-heterocyclic含有硫的化合物.pdf

Molecules 2009, 14, 1904-1914; doi:10.3390/molecule OPEN ACCESS molecules ISSN 1420-3049 /journal/molecules Article Synthesis and Analysis of Some Bis-Heterocyclic Compounds Containing Sulphur Yahia Nasser Mabkhoot Department of Chemistry, King Saud University P.O Box 2455, Riyadh-11451, Saudi Arabia; E-mail: yahia@.sa Received: 1 April 2009; in revised form: 15 May 2009 / Accepted: 19 May 2009 / Published: 22 May 2009 Abstract: A facile and convenient synthesis of a series of bisheterocycles 7a,b 10, 12 and 13a,b containing a thieno[2,3-b]thiophene base unit via the versatile, hitherto unreported 3- [3,4-dimethyl-5-(3-nitrilopropanoyl)thieno[2,3-b]thiophen-2-yl]-3-oxopropanenitrile (4) is described. Keywords: DMF-DMA; bis-thieno[2,3-b]thiophene; bis-aminopyrazole; bis- pyrazolopyrimidine Introduction Thiophene derivatives represent a class of important and well-studied heterocycles [1,2]. The interest in this kind of heterocycles has spread from the early dye chemistry to modern drug design, biodiagnostics, electronic and optoelectronic devices, conductivity-based sensors, and self-assembled superstructures [3-8]. Recently, some conjugated thieno-thiophenes, structurally related to several current applications have been reported [9-15]. Thienothiophene derivatives have been developed for different purposes in the pharmaceutical field and have been tested as potential antitumor, antiviral, antibiotic, and antiglaucoma drugs, or as inhibitors of pla