We present a computational study of the magnetic circular dichroism (MCD) spectra in the 200-300 nm wavelength region of purine and its derivative hypoxanthine, as well as of the pyrimidine bases of nucleic acids uracil, thymine, and cytosine, using the B3LYP and CAM-B3LYP functionals. Solvent effects are investigated within the polarizable continuum model and by inclusion of explicit water mol...

Purine nucleotide analogs with reactive functional groups at various positions of the purine or ribose ring can be effective in mapping the active sites and regulatory sites of kmases and dehydrogenases. We have synthesized 5’-p-fluorosulfonylbenzoyl (FSB) derivatives of adenosine, guanosine, 8-azidoadenosine and the fluorescent l,r&-ethenoadenosine in which the electrophilic FSB moiety occupie...

A study of the degree of reproducibility of the Carcinoma 755 system when employed to obtain therapeutic indices of purine antagonists has been carried out. Some 60 "active" purine analogs have been studied by this system, used in a quantitative manner, and the approximate LD10's, minimum effective doses, therapeutic indices (LD10/T/C 0.10), and maximum degrees of effectiveness (T/C at the LD10...

Experimental systems using non-growing cell of Eremothecium ashbyii to elucidate the mechanism of flavinogenesis were established in this paper. 1. It was found that vacuum infiltration of purines for 2, 3 and 5min and moderate shaking of non-growing cell brought about a good reproducibility of the stimulatory effects on flavinogenesis by purines and furthermore, a higher flavinogenesis. 2. The...

besides being a metabolite of nucleotides like atp, adenosine is a mediator of neuronal function in the central nervous system. its actions are mediated by at least three extracellular receptors. in this review different aspects of adenosine such as biosynthesis, release, inactivation and its receptors are discussed. it also covers pre- and postsynaptic effects as well as postreceptor mechanism...

An< accurate, stable and very fast corner finder (for feature based vision) has been developed', based on a novel definition of corners, using:no image derivatives. This note describes the algorithm and the results obtained from its use.

Formation of mixed-ligand Pd2+ complexes between canonical nucleoside 5'-monophosphates and five metal-ion-binding nucleoside analogs has been studied by 1H-NMR spectroscopy to test the ability of these nucleoside surrogates to discriminate between unmodified nucleobases by Pd2+-mediated base pairing. The nucleoside analogs studied included 2,6-bis(3,5-dimethylpyrazol-1-yl)-, 2,6-bis(1-methylhy...

The structural requirements for the binding of purines to adenine phosphoribosyltransferase from monkey liver were explored by the determination of the K; values for 67 purines and purine analogues. Adenine was bound 40 times better than the most effectively bound analogues. Substitutions on the 6-amino group of adenine decreased binding to varying degrees. The hydroxylaminoand hydrazinopurines...