The structures and relative stabilities of the complexes formed by uracil and its sulfur derivatives, namely, 2-thio-, 4-thio, and 2,4-dithio-uracil when interacting with Ca(2+) in the gas phase have been analyzed by means of density functional theory (DFT) calculations carried out at the B3LYP/6-311++G(3df,2p)//B3LYP/6-31+G(d,p) level. For uracil and 2,4-dithiouracil, where the two basic sites...

Nonnucleoside reverse transcriptase (RT) inhibitors (NNRTIs) are important components of current combination therapies for human immunodeficiency virus type 1 (HIV-1) infection. In screening of chemical libraries, we found 6-azido-1-benzyl-3-(3,5-dimethylbenzyl)uracil (AzBBU) and 6-amino-1-benzyl-3-(3,5-dimethylbenzyl)uracil (AmBBU) to be highly active and selective inhibitors of HIV-1 replicat...

a practical and new method for the synthesis oxindole substituted pyrrolo[2,3-d]pyrimidines by the condensation of isatin, acetophenone and 6-amino-uracil under ultrasound irradiation conditions at 60 °c was described. the reaction was developed via a sequential tandem process to afford the oxindole substituted pyrrolo[2,3-d]pyrimidines in good to excellent yields. all reactions performed effic...

Density functional theory (DFT) calculations were performed to investigate the effects of a carbon nanotube (CNT) on the properties of the fluorouracil (F-Uracil) anticancer drug. To achieve the purpose, a molecular model including both of F-Uracil and CNT molecules was created to represent the CNT@F-Uracil compound. The optimized parameters indicated that the new compound could show new proper...

A revival of interest has taken place in recent years in the possibility of interference with mam malian nucleic acid biosynthesis by means of an tagonists of the free pyrimidines. Early studies appeared to show that, while orotic acid (1, 48) and the sugar derivatives of the pyrimidines (19, 20) are extensively incorporated into both RNA and DNA, the incorporations of free uracil, cytosine, an...

In this paper,the molecular geometry for three tautomers of uracil and four tautomers of cytosine has been analyzed. vibrational IR spectra of the tautomers were   investigated at HF and B3LYP level using the AB initio 6-31G* and LANL2DZ basis sets from the program package Gaussian 98 (A.7 Public Domain version). The physico-chemical and biochemical properties of uracil and cytosine are one of...

The 6-anilinouracils are novel dGTP analogs that selectively inhibit the replication-specific DNA polymerase III of gram-positive eubacteria. Two specific derivatives, IMAU (6-[3'-iodo-4'-methylanilino]uracil) and EMAU (6-[3'-ethyl-4'-methylanilino]uracil), were substituted with either a hydroxybutyl (HB) or a methoxybutyl (MB) group at their N3 positions to produce four agents: HB-EMAU, MB-EMA...