Browsing Chemistry by Title

Now showing items 267-286 of 342

Rational approach to selective and direct 2-O-alkylation of 5,6-O-isopropylidine-L-ascorbic acid

Olabisi, Ayodele O.; Wimalasena, Kandatege (American Chemical Society, 2004-10-15)

l-Ascorbic acid is a versatile radical scavenger widely distributed in aerobic organisms that plays a central role in the protection of cellular components against oxidative damage by free radicals and oxidants. It also ...
The rational synthesis of chlorins via rearrangement of porphodimethenes: influence of beta-substituents on the regioselectivity and stereoselectivity of pyrroline ring formation

Burns, Dennis H.; Li, Yue He; Shi, Dong C.; Caldwell, Timothy M. (American Chemical Society, 2002-06-28)

The porphodimethene rearrangement methodology reported in this paper provides for a rational, step-by-step synthesis of chlorins from readily available pyrrole precursors. The intermediate porphodimethenes are furnished ...
Recent advances in cyanoscorpionate chemistry: complexes with CO(II), MN(II), and NI(II)(cyclam)

Bullinger, John C.; Moore, Curtis E.; Eichhorn, David M. (Wichita State University. Graduate School., 2008-04-25)

In the past, electronic and magnetic materials have been atom based materials made up of metals or metal-oxides. Functionally,these atom based materials are extremely efficient, however, they are very expensive to synthesize, ...
Recent developments in the design of mechanism-based and alternate substrate inhibitors of serine proteases

Zhong, Jiaying; Groutas, William C. (Bentham Science, 2004-01-01)

A wide range of human diseases are associated with the aberrant activity of mammalian, viral, bacterial or parasitic proteases. These include members of all four classes of proteases, namely, serine, cysteine, aspartic and ...
Reduction of dopamine beta-monooxygenase. A unified model for apparent negative cooperativity and fumarate activation

Wimalasena, Kandatege; Dharmasena, Silpadipathialage; Wimalasena, D. Shyamali; Hughbanks-Wheaton, Dianna K. (American Society for Biochemistry and Molecular Biology, 1996-10-18)

The interactions of reductants with dopamine beta-monooxygenase (DbetaM) were examined using two novel classes of reductants. The steady-state kinetics of the previously characterized DbetaM reductant, N,N-dimethyl-1,4-p ...
The reduction of membrane-bound dopamine beta-monooxygenase in resealed chromaffin granule ghosts. Is intragranular ascorbic acid a mediator for extragranular reducing equivalents?

Wimalasena, Kandatege; Wimalasena, D. Shyamali (American Society for Biochemistry and Molecular Biology, 1995-11-17)

The role of internal and external reductants in the dopamine beta-monooxygenase (D beta M)-catalyzed conversion of dopamine to norepinephrine has been investigated in resealed chromaffin granule ghosts. The rate of ...
Results compared for tricyclic antidepressants as assayed by liquid chromatography and enzyme immunoassay

Dorey, R. Cameron; Preskorn, Sheldon H.; Widener, Pamela K. (P.B. Hoeber, 1988-11-01)

The tricyclic antidepressants amitriptyline, nortriptyline, imipramine, and desipramine in serum of patients taking one of the drugs were quantified in two laboratories by high-performance liquid chromatography (HPLC) and ...
The role of charge in the surfactant-assisted stabilization of the natural product curcumin

Wang, Zifan; Leung, Mandy H. M.; Kee, Tak W.; English, Douglas S. (American Chemical Society, 2010-04-20)

Colloidal solutions of surfactants that form micelles or vesicles are useful for solubilizing and stabilizing hydrophobic molecules that are otherwise sparingly soluble in aqueous solutions. In this paper we investigate ...
Sandwich compounds of cyanotrispyrazolylborates: complexation-induced ligand isomerization

Zhao, Ningfeng; Van Stipdonk, Michael J.; Bauer, Cary; Campana, Charles; Eichhorn, David M. (American Chemical Society, 2007-10-15)

Reaction of the new cyanoscorpionate ligand, hydrotris(4-cyano-3-phenyl)pyrazolylborate (Tp(Ph),(4CN)) with Co(II), Mn(II), and Fe(II) unexpectedly results in the isolation only of crystals containing sandwich complexes ...
Self-Assembled Porphyrin-C(60) and Porphycene-C(60) Complexes via Metal Axial Coordination

D'Souza, Francis; Deviprasad, Gollapalli R.; Rahman, Muhammad S.; Choi, Jai-pil (American Chemical Society, 1999-05-03)

Noncovalently linked electron donor-acceptor complexes consisting of either zinc tetraphenylporphyrin, (TPP)Zn, or zinc octaethylporphycene, (OEPc)Zn, as donor and pyridine appended C(60), py approximately C(60), as acceptor, ...
Self-assembled single-walled carbon nanotube:zinc-porphyrin hybrids through ammonium ion-crown ether interaction: construction and electron transfer

D'Souza, Francis; Chitta, Raghu; Sandanayaka, Atula S. D.; Subbaiyan, Navaneetha K.; D'Souza, Lawrence; Araki, Yasuyaki; Ito, Osamu (John Wiley and Sons, 2007-01-01)

An ammonium ion-crown ether interaction has been successfully used to construct porphyrin-single-walled carbon nanotube (SWNT) donor-acceptor hybrids. The [18]crown-6 to alkyl ammonium ion binding strategy resulted in ...
Self-assembled via axial coordination magnesium porphyrin-imidazole appended fullerene dyad: spectroscopic, electrochemical, computational, and photochemical studies

D'Souza, Francis; El-Khouly, Mohamed E.; Gadde, Suresh; McCarty, Amy L.; Karr, Paul A.; Zandler, Melvin E.; Araki, Yasuyaki; Ito, Osamu (American Chemical Society, 2005-05-26)

Spectroscopic, redox, and electron transfer reactions of a self-assembled donor-acceptor dyad formed by axial coordination of magnesium meso-tetraphenylporphyrin (MgTPP) and fulleropyrrolidine appended with an imidazole ...
Sensitive efficiency of photoinduced electron transfer to band gaps of semiconductive single-walled carbon nanotubes with supramolecularly attached zinc porphyrin bearing pyrene glues

Maligaspe, Eranda; Sandanayaka, Atula S. D.; Hasobe, Taku; Ito, Osamu; D'Souza, Francis (American Chemical Society, 2010-06-16)

Photoinduced electron transfer in self-assembled single-walled carbon nanotube (SWNT)/zinc porphyrin (ZnP) hybrids utilizing (7,6)- and (6,5)-enriched SWNTs has been investigated. Toward this, first, zinc porphyrin was ...
Separation of dideoxyribonucleosides in trace amounts by automated liquid chromatography and capillary electrophoresis

Singhal, Ram P.; Hughbanks, D.; Xian, Jun (Elsevier, 1992-09-18)

No satisfactory high-performance liquid chromatographic (HPLC) method is currently available for the separation of the major dideoxyribonucleosides (ddNs) and their derivatives. A method involving HPLC has been developed ...
Separation of metallic and semi conducting SWNTs by density gradient ultracentrifugation and formation of donor-acceptor hybrids using porphyrins

Das, Sushanta K. (Wichita State University. Graduate School, 2010-04-23)

Occurrence of photo induced electron transfer in donor-acceptor self-assembled Zinc porphyrin (ZnP) and C₀M₀CAT single walled carbon nanotube (SWNT) nanohybrid has been demonstrated. C₀M₀CAT (6,5) and C₀M₀CAT(7,6) SWNT ...
Serendipitous discovery of an unexpected rearrangement leads to two new classes of potential protease inhibitors

Zhong, Jiaying; Lai, Zhong; Groutas, Christopher S.; Wong, Tzutshin; Gan, Xiangdong; Alliston, Kevin R.; Eichhorn, David M.; Hoidal, John R.; Groutas, William C. (Elsevier, 2004-12-01)

The pathogenesis of a range of human diseases arises from the aberrant activity of proteolytic enzymes. Agents capable of selectively modulating the activity of these enzymes are of potential therapeutic value. Thus, there ...
Simulated speed distributions for effusing gases in the transition region

Wahlbeck, Phillip G. (American Chemical Society, 2005-10-06)

Monte Carlo techniques were used to evaluate the flow of molecules through an ideal orifice (effusion) as predicted by isotropy-failure theory. Binary collisions of molecules were treated using classical mechanics with ...
A slow-tight binding inhibitor of dopamine beta-monooxygenase: a transition state analogue for the product release step

Dharmasena, Sanjeewa P.; Wimalasena, D. Shyamali; Wimalasena, Kandatege (American Chemical Society, 2002-10-15)

The steady-state kinetic data show that 3-hydroxy-4-phenylthiazole-2(3H)-thione (3H4PTT) is a potent tight-binding inhibitor for dopamine beta-monooxygenase (DbetaM) with a dissociation constant of 0.9 nM. Ackermann-Potter ...
Solution properties of the iron(II) tris-bipyrazine cation

Kirgan, Robert A.; Rillema, D. Paul (Wichita State University. Graduate School., 2005-04-22)
Spectral and electrochemical investigations on the "tail-on" and "tail-off" mechanism in pyridine covalently bound zinc(II) porphyrins

D'Souza, Francis; Hsieh, Yi-Ying; Deviprasad, Gollapalli R. (American Chemical Society, 1996-09-11)