Abstract Thienopyrimidine derivatives hold a unique place between fused pyrimidine compounds. They are important and widely represented in medicinal chemistry as they structural analogs of purines. have various biological activities. The current review discusses different synthetic methods for the preparation heterocyclic thienopyrimidine derivatives. It also highlights most recent research on ...

The method of Zinn & Owens (1986; Canadian Journal of Animal Science 66, 157-166), based on release of purine bases by HClO4 followed by their precipitation with AgNO3, was used to study recovery of purines from lyophilized rumen microbial or Escherichia coli preparations added to matrices such as cellulose, starch and neutral-detergent fibre. The recovery of purines was poor (approximately 50%...

The uptake of radioactive purines in resting cell suspensions of Bacillus subtilis has been studied. Initial rates of uptake obeyed saturation kinetics (e.g. apparent Km adenine, 0.6 PM). Subsequent uptake proceeded in steplike increments. Further studies were aimed at delineating the control mechanism for this uptake. Purines were highly concentrated with respect to the medium, but the intrace...

Studies of the metabolism of purines and pyrimidines have been made in a variety of ways. Man, rats, pigeons, yeast, Neurospora, and bacteria have been used as experimental organisms. Edson, Krebs, and Model (2) have shown that ammonia and lactate stimulate the production of hypoxanthine by pigeon liver slices. Ammonia labeled with N15 was shown by Barnes and Schoenheimer (3) to be utilized in ...

Duza, Tasmia, and Ingrid H. Sarelius. Conducted dilations initiated by purines in arterioles are endothelium dependent and require endothelial Ca2 . Am J Physiol Heart Circ Physiol 285: H26–H37, 2003. First published March 13, 2003; 10.1152/ajpheart.00788.2002.—The signaling pathways underlying the regulation of vascular resistance by purines in intact microvessels and particularly in communica...