Nandibewoor, "Staircase voltammetric determination of 2-thiouracil
in pharmaceuticals and human biological fluids at polyaniline and polypyrrole film modified sensors," Sensors and Actuators A: Physical, vol.
Interactions of 5-fluorouracil (5-FU), a commercially available anti-cancer drug and two other possibly anti-cancer actives, 2-thiouracil (2-TU) and 2,4-dithiouracil (DTU), with anionic sodium dodecyl sulphate (SDS) and cationic cetlytrimethyl ammonium bromide (CTAB) surfactants were studied using cyclic voltammetry and UV-Visible spectroscopic techniques.
2-thiouracil (2-TU) and 2,4- dithiouracil (DTU) are known as effective neoplastigen, tumorigen, carcinogen and teratogen agents.
High purity (=99%) chemicals 2-Thiouracil (2-TU), 2,4-dithiouracil (DTU), 5-fluorouracil (5-FU), sodiumdodecylsulphate (SDS), and cetyltrimethylammonium bromide (CTAB), were purchased from Sigma and were used as received without any further purification.
2-thiouracil (Scheme 1) and its derivatives also act as selective inhibitors of nitric oxide synthase (NOS) .
To our knowledge, voltammetric determination of 2-thiouracil using GCE has not been reported so far.
The powdered form of 2-thiouracil was obtained from Sigma Aldrich and used without further purification.
Then electrodes were transferred into another 10 mL of phosphate buffer (pH 3.0) containing proper amount of 2-thiouracil. After accumulating for 10 s at open circuit under stirring and following quiet for 10 s, potential scan was initiated and cyclic voltammograms were recorded between -1.2 and 2.0 V, with a scan rate of 50 mV [s.sup.-1].
Cyclic Voltammetric Behavior of 2-Thiouracil. In order to understand the electrochemical behaviour at the glassy carbon electrode, cyclic voltammetry was carried out with 2-thiouracil between pH 3.0 and 10.4 of phosphate buffer, which produced two well-defined oxidation peaks and one reduction peak.
Outcome of Structure Activity Relationship (SAR) study depicted the thiouracil nucleus as essential for the antimicrobial activity and substitution at position 5 of 2-thiouracil
gave active compounds as antibacterial, antiviral, and antineoplastic; hence, the substituents group like thiourea in compound (86), pyridine moiety in compound (87), benzene nucleus with N[O.sup.2] group in compound (88), and thiazole ring in compound (89) were found to show potent in vitro antimicrobial activity .
Kedzia, "Synthesis and antimicrobial properties of S-substituted derivatives of 2-thiouracil
," Farmaco, vol.
Third investigation  showed that all investigated uracils interact hydrophobically with HRP heme group, but the measurements showed that only the thiouracil derivatives 2-thiouracil
and of 6-n-propyl-2-thiouracil inhibit HRP activity (noncompetitively).