The 1-hydroxy-1-methyl-6,6-diphenyl-5-hexenyl radical (4a) and the 1-hydroxy-1-methyl-7,7-diphenyl-6-heptenyl radical (4b) were prepared from the corresponding PTOC esters (anhydrides of a carboxylic acid and N-hydroxypyridine-2-thione). The key step in the synthetic method for the precursors was a coupling reaction of the respective carboxylic acids with the thiohydroxamic acid, which was cond...

Decyl and phenyl disulfide derivatives of 6-mercaptopurine and 6-thioguanine (6-TG) were examined for antineoplastic activity under aerobic and hypoxic conditions toward EMT6 cells in culture. Although these derivatives did not display selective toxicity toward the hypoxic cells, they were significantly more toxic than 6-TC to this cell line at 500 microM after a 2-h exposure. In conjunction wi...

a new al(iii) selective membrane based on 5-bromo(salicylidene-2-amino thiophenol) as a neutral carrier in a poly(vinyl chloride) (pvc) matrix is coated on platinum wire to determine trace amounts of al(iii) ion in various samples. the sensor exhibits a good response for al(iii) ion over a wide concentration range of 5.20 × 10-7 to 1.00 × 10-2 m  with nernstian slope of 19.64 ± 0.15 mv decade-1...

New cationic diruthenium complexes of the type [(arene)(2)Ru(2)(SPh)(3)](+), arene being C(6)H(6), p-(i)PrC(6)H(4)Me, C(6)Me(6), C(6)H(5)R, where R = (CH(2))(n)OC(O)C(6)H(4)-p-O(CH(2))(6)CH(3) or (CH(2))(n)OC(O)CH=CHC(6)H(4)-p-OCH(3) and n = 2 or 4, are obtained from the reaction of the corresponding precursor [(arene)RuCl(2)](2) and thiophenol and isolated as their chloride salts. The complexe...

The absorption spectra of the hydroxycyclohexadienyl radicals formed upon the addition of OH radicals to six substrates for phenol hydroxylase have been determined using pulse radiolysis. Combining the radical spectra of thiophenol (lambda max, 390 nm; epsilon, 10,500 M-1 cm-1) and resorcinol (lambda max, 340 nm; epsilon, 4,100 M-1 cm-1) with their respective published spectra of enzyme-bound r...

The chemical reactivity of 8-chloroflavins and 8-mercaptoflavins has been exploited in order to examine the orientation of protein-bound flavins relative to solvent. The apoprotein form of a series of flavoproteins was prepared and the native flavin was replaced by either 8-C1-flavin or 8-mercaptoflavin (FAD, FMN, or riboflavin form as was appropriate). The reconstituted proteins were exposed t...

A controllable flower-like Au nanostructure array for surface-enhanced Raman scattering (SERS) was fabricated using the combined technique of the top-down approach of conventional photolithography and the bottom-up approach of electrodeposition. Au nanostructures with a mean roughness ranging from 5.1 to 49.6 nm were obtained by adjusting electrodeposition time from 2 to 60 min. The rougher Au ...

We report the formation and characterization of self-assembled monolayers (SAMs) derived from the adsorption of 4-mercaptophenylboronic acid (MPBA) on gold. For comparison, SAMs derived from the adsorption of thiophenol (TP), 4-mercaptophenol (MP), and 4-mercaptobenzoic acid (MBA) were also examined. The structure and properties of the SAMs were evaluated by ellipsometry, contact-angle goniomet...

We have demonstrated a surface-enhanced Raman scattering (SERS) substrate capable of detecting 1 pM of benzenethiol (BT) and developed better understanding of its enhancing mechanism by varying the fabrication process and also performing detailed simulation studies. The extreme enhancement originates from the three dimensionally fabricated and optimized substrate, which is made of Au-nanopartic...