Joseph Nagyvary

• Doctor of Philosophy
• Professor Emeritus retired in 2003 at Texas A&M University

Reaching back to his discontinued research done some 50 years ago, a retired chemist proposes novel synthetic routes to 3′-thiocytidylates and their polymers. The driving force of these reactions is based on the superior nucleophilicity of the thiophosphate anion coupled with charge interactions in facilitating displacement reactions on anhydrocyti...

Heritage Science Im Forschungsartikel auf S. 19293 nutzen Hwan-Ching Tai et al. ICP-MS, um die einzigartige Mineralienrezeptur zu identifizieren, die Antonio Stradivari zur Behandlung seines Fichtenholzes, des Materials für die Geigendecke, verwendete.

Heritage Science In their Research Article on page 19144, Hwan-Ching Tai et al. use ICP-MS to identify the unique mineral recipe used by Antonio Stradivari to treat his spruce wood, the material for the violin top plate.

ICP-MS is used to identify the unique mineral recipe used by Antonio Stradivari to treat his spruce wood, the material for the violin top plate. Chemical manipulation led to hemicellulose fragmentation and cellulose rearrangement. Incorporating engineered wood may contribute to the unique tonal qualities of these acclaimed instruments. Abstract We...

We investigated the material properties of Cremonese soundboards using a wide range of spectroscopic, microscopic, and chemical techniques. We found similar types of spruce in Cremonese soundboards as in modern instruments, but Cremonese spruces exhibit unnatural elemental compositions and oxidation patterns that suggest artificial manipulation. Co...

By the sheer beauty of its vibrant sound, the voice of the violin can be intimate and enchanting like no other musical instrument. The enormous complexity of this odd resonator box has long attracted some of the best minds in science to play on it and think about how it functions. The letters of Galileo, for example, show how impatiently he awaited...

The enormous progress in the area of ATP synthesis during the 1990s has not yet been communicated to students through biochemistry textbooks. In this article, we summarize the breakthroughs in the elucidation of the structure of F0F1-ATPase/synthase, and relate this information to previous and new kinetic mechanisms and bioenergetic considerations....

Following the futile efforts of generations to reach the high standard of excellence achieved by the luthiers in Cremona, Italy, by variations of design and plate tuning, current interest is being focused on differences in material properties. The long-standing question whether the wood of Stradivari and Guarneri were treated with wood preservative...

Data for multivariate discriminant analysis. The full set of data included 95×12 values for the Stradivarius violin, 75×12 for the early Guarneri and 30×12 for the rest, with the exception of the German maple which had only 15×12 data points. The data set from the pellets from each musical instrument was analyzed in its entirety as one group, while...

Whether or not the great Italian violin-makers used wood that had been chemically processed in order to preserve it and enhance the instrument's sound quality has long been a contentious issue. Here we use nuclear magnetic resonance and infrared spectroscopy to analyse organic matter in wood taken from antique instruments made by Stradivari and Gua...

The lipid binding capacity of chitosan (partially deacetylated chitin) was determinined with respect to micellar solutions of bile salts, dodecyl sulfate, natural ox bile and an artificial mixed microemulsion. The stoichiometry was determined following the separation of the solid phase by filtration or centrifugation. The major variables in the ext...

This communication describes the synthesis of 5′-deoxy-5′-chloro-3′-(2-thio-1,3,2-dioxaphosphorinanyl)thymidine, N4,2′,3′-triacetyl-5′-(2-thio-1,3,2-dioxaphosphorinanyl)-1-β-D-arabinosyl-cytosine and N4-acetyl-5′-(2-thio-1,3,2-dioxaphosphorinanyl)-1-β-D-arabinosylcytosine.

This study was undertaken to elucidate the mechanism responsible for the hypolipidemic action of pectin. The experiments reported here were designed to test if direct molecular interactions exist between pectin and lipids. Equilibrium dialysis of pectin and taurocholate showed binding only at high nonphysiological ionic strength. When lipid microem...

Aus dem Anhydro-nucleosid (I) erhält man mit Phosphorpentasulfid über (II) die Verbindungen (III) und (IV).

A mechanism is proposed for the prebiotic synthesis of deoxyribonucleotides and possible nucleic acid analogs from ribonucleotides by a pathway involving 2'-thio-2'-deoxyribonucleosides. The mechanism is supported by laboratory experiments in which 2'-thio-2'-deoxycytidine was synthesized from anhydro arabinosyl cytosine in dithiophosphate and CS2....

In order to assess the significance of the 2′-position of nucleosides, the nucleoside analogue 2′-deoxy-2′-thiocytidine was synthesized by using 2,2′-anhydro-1-β-D-arabinosylcytosine and P 2S 5 as starting materials. Several thiophosphorylated derivatives were also obtained as synthetic intermediates and characterized by NMR spectroscopy and elemen...

We prepared the 5'- and 3'-O-phosphorothioate esters of the antitumor agent O2 : 2'-anhydro-1-beta-D-arabinosylcytosine. We also included in this study esters of 2'-thio-2'-deoxycytidine, namely, 2'-S-dCyd-2' : 3'-P, 2'-S-dCyd-2'-P, and 2'-S-dCyd-3'-P, along with natural nucleotides. These compounds were subjected to the action of Escherichia coli...

Two types of reactivities of thiophosphates have been demonstrated: one being nucleophilic displacement by the P-S moiety of nucleoside phosphorothioates and the other, phosphorylation via P-S cleavage as the driving force. We have designed a system where both displacement on carbon and P-S cleavage are possible. Adenosine derivatives have been syn...

The isolation of pyrimidine oligonucleotides (isostichs) from chick erytyrocyte DNA was accomplished on a preparative scale with the goal of providing starting material for further chemical modifications. The DNA was degraded by the method of Burton and Petersen and the isostichs were obtained via paper chromatography and ion-exchange chromatograph...

Anhydro-araC, a precursor of araC, exhibits an unusual tissue distribution and unexpected toxicities which require an interpretation. In order to provide an explanation of these phenomena, we studied the nature of binding of anhydro-araC to some proteins and acid mucopolysaccharides in vitro using equilibrium dialysis and potentiometric titration....

We are proposing a simple model by which acidic polysaccharides of the critical charge density 1 minus/1 carbohydrate unit can be converted into anion exchangers by complexing with a trivalent cation. We have constructed a complex of alginic acid and Al3+ which was shown to bind nucleotides. It was assumed that bile acids would also be bound and, t...

Oligomerization of 5' -TMP in water pools entrapped by dodecyl-ammonium chloride surfactant aggregates in benzene: hexane in the presence of dicyanodiimide at temperatures ranging from 21 degree -72 degree resulted in the formation of linear and cyclic oligonucleotides containing up to pentamers. Effects of temperature, time and surfactants have be...

The synthesis of a novel ribonucleotide analog 2'-thio-2' deoxycytidine 2':3'-O,S-phosphorothioate is described. In the first step, 2,2'-anhydro 1-beta-D-arabinosylcytosine was thiophosphorylated by the action of dithiophosphate, a process which gave predominantly the 3'-O-phosphorothioate isomer. An intramolecular displacement reaction led to the...

The partition coefficients, K-values, of adenosine, guanosine, cytidine, uridine, 51-adenylic acid (AMP), 51-guanylic acid (GMP), 51-cytidylic acid (CMP), and 51-uridylic acid (UMP) between water and aqueous sodium dodecanoate has been determined by gel filtration on Sephadex G-25. Below the critical micelle concentration of the surfactant, K-value...

The biochemical properties of several alkyl phosphotriesters of cyclic AMP were studied with respect to their interactions with beef heart protein kinase and cyclic nucleotide phosphodiesterase. Ethyl and propyl triesters did not enhance the phosphorylation of histone by protein kinase and methyl, ethyl, propyl and butyl triesters were poor competi...

Cationic amino acids, arginine and lysine partition differentially from water into aqueous micellar sodium dodecanoate. Conversely, partitioning of serine, glycine, aspartic acid, glutamic acid, threonine, alanine, proline, valine, leucine, phenylalanine and isoleucine do not vary appreciably. Partitioning from neat hexane into dodecylammonium prop...

Cationic amino acids, arginine and lysine partition differentially from water into aqueous micellar sodium dodecanoate. Conversely, partitioning of serine, glycine, aspartic acid, glutamic acid, threonine, alanine, proline, valine, leucine, phenylalanine and isoleucine do not vary appreciably. Partitioning from neat hexane into dodecylammonium prop...

The P-O-ethyl ester of cAMP has been synthesized, its inhibition of solid and ascites tumors studied, and its pattern of urinary excretion followed. Et-cAMP is more effective than cAMP against solid sarcoma 180 in mice and against Ehrlich ascites carcinoma cells in tissue culture. The urinary excretion pattern of injected E-t-cAMP suggests that abo...

An improvement of our strategy for the stepwise synthesis of oligo 5′-deoxy-5′-thiodeoxyribonucleotides [Chladek and Nagyvary (1972) J. Amer. Chem. Soc. 94, 2079] involves the use of 5′-0-tosylthymidine 3′-S-2-cyanoethyl phosohorothioate. The displacement of the tosylate by thymidine 3′-phosphorothioate and subsequent alkaline deblocking afforded t...

Cyclic AMP was converted to its phosphotriesters according to the classical approach of phosphate activation with a sulfonyl chloride, followed by esterification with an alcohol. The methyl, ethyl, propyl, butyl and cetyl triesters were prepared, and some of their physical-chemical properties determined. Alkaline hydrolysis of these alkyl phosphotr...

Selective compartmentalization of amino acids and nucleotides according to their polarities is proposed as a physical-chemical model for the origin of the genetic code. Assumptions made in this hypothesis are: (1) an oil-slick covered the surface of the primitive ocean, constituents of which formed association colloids or micelles at the water-oil-...

Die Trinucleosid-monophosphate (Ia)-(Ic) werden in ihrer Herstellung sowie′ in ihrem pharmakologischen Verhalten diskutiert.

Summary It is proposed that inorganic thiophosphate was a versatile and highly reactive constituent of the primitive earth. Some of the ramifications of this assumption with regard to prebiotic chemistry stem from the dual nature of thiophosphate as the most superior nucleophilic agent and an energy rich phosphate. The Michael addition of thiophosp...

Methyl and ethyl esters of cyclic AMP were obtained by a straightforward triesterification procedure. Both compounds are resistant to enzymes and undergo slow chemical hydrolysis at physiological pH. P-O-Methyl diacetyl cyclic AMP was found more toxic than the parent compound on Ehrlich ascites carcinoma cells, Chinese hamster ovary cells, and chic...

Changes in the carbohydrate, the base, or the phosphate component of nucleosidic or nucleotidic ligands to pancreatic ribonuclease A have been evaluated. The association constants with ribonuclease A of various compounds which can be obtained by combinations of uracil, cytosine, ribose, arabinose, and the phosphate group were determined. The hydrol...

Several modifications of 1-β-d-arabinosylcytosine (ara-C) are described with particular regard to prolonging its presence in the tissues and lowering its toxicity. Precursors containing an isourea-ether or amidine group and a phosphate group were synthesized and studied in vitro. The most promising compound satisfying these criteria is O2:2'-anhydr...

The observation that the cytidine analog, O2:2'-anhydro-l-β-D-arabinosylcytosine 3'-phosphate (anhydro-ara-CMP), yields 1-β-D-arabinofuranosylcytosine (ara-C) as a degradation product in vitro, prompted us to investigate the metabolism of [14C]-anhydro-ara-CMP in mice. This study includes measurements of excretory rates and appearance of labeled ma...

Thermal activation of O2,5'-cyclothymidine 3'-phosphate in solution and in the solid state led to the formation of thymidine oligonucleotides containing up to approximately 12 nucleotide units. Only the 3',5' internucleotide diester bonds were formed. This polymerization occurs without the addition of any activating agent or catalyst.

Aus den Tosylnucleosiden (Ia) werden durch Umsetzung mit PSCl3 und nachfolgend mit Hydracrylonitril die Thiophosphorsäure-Derivate (Ib) dargestellt, die nach alkalischer Hydrolyse der Cyanäthylgruppe einer intramolekularen Verdrängungsreaktion unter Bildung der cyclischen Verbindungen (II) unterliegen.

The synthetic intermediates 5′-O-tosylthymidine 3′-cyanoethyl phosphorothioate, 5′-O-tosyl-N4-benzoyldeoxycytidine 3′-cyanoethyl phosphorothioate, and 5′-O-tosyl-N6-benzoyldeoxyadenosine 3′-cyanoethyl phosphorothioate were prepared by the reaction of the corresponding 5′-O-tosylnucleosides with PSCl3, followed by a treatment with hydracrylonitrile....

IN contrast to the plausible explanations for proteinoid formation1, there seems to be no satisfactory concept for the genesis of polynucleotide templates in the presumed conditions of the primitive Earth. Only parts of the problem, such as the origin of the bases2,3 and carbohydrates4 and the synthesis of short oligonucleotides5,6, have been subje...

Oligo 5′-thiodeoxythymidylates and oligo 5′-thiodeoxyadenylates were prepared via displacement of tosylates by thiophosphate mono- and diesters. The 5′ ends contain O-tosyl or S-phosphoryl groups, while the 3′ ends terminate in deoxythymidine. The types of starting materials used for such polymerization were 5′-O-tosyl nucleoside 3′ cyanoethyl phos...

A novel reaction of ribooligonucleotides involves the conversion of the ribose moiety of the pyrimidine nucleotides into derivatives of β-D-arabinose without breaking the 3′-5′-internucleotide bonds. The reaction consists of three steps: (1) an activation which generates 2′:3′→5′-cyclic triesters, (2) a thermal rearrangement which produces 3′-5′-li...

The reaction of an excess of 2′,3′-O-isopropylidene-O2,5′-cyclouridine with the monoanionic form of p-nitrophenyl phosphate, uridine 5′-phosphate, and thymidine 3′-phosphate at and over 100° gave a mixture of the mono- and di-2′,3′-O-isopropylideneuridine 5′-esters of these phosphates. This reaction represents the first direct synthesis of trinucle...

By chemical degradation and analysis of nmr spectra formula I for C-curarine was deduced; the halochromic reactions of the alkaloid are briefly discussed.