Shib P. Dutta

Isolation and Characterization of a Novel Nucleoside from the Urines of Chronic Myelogenous Leukemia Patients

Abstract From 24 hour collections of urines of chronic myelogenous leukemia (CML) patients, a novel nucleoside was isolated. It was assigned the structure, 5′-deoxyinosine (I) on the basis of UV, NMR and mass spectrometry and by comparison of the spectral data and HPLC and TLC mobilities with those of the authentic sample. Another nucleoside, 5′-deoxy-5′-methylthioadenosine sulfoxide previously isolated from the urines of immunodeficient children was also found in the urine of a CML patient. Possible origin and significance of both of these nucleosides are discussed.

Isolation and Characterization of 3-(3-Amino-3-Carboxypropyl)Uridine from Human Urine

Abstract A new modified nucleoside, 3-(3-amino-3-carboxypropyl)-uridine was isolated from a 24 hour collection of a normal human urine. The structure was assigned on the basis of UV, NMR and mass spectrometry data and confirmed by comparison of the spectral data and HPLC mobilities with those of an authentic sample. Origin and significance of this nucleoside in relation to tRNA is discussed. The new nucleoside is present also in the urine of cancer patients but in smaller amounts.

Structure and Conformation of 1-β-D-Ribofuranosylpyridin-4-One-3- Carboxamide, A Novel Nucleoside from Human Urine with a Rare Ribose Pucker

Abstract The pyridine nucleoside, 1-β-d-ribofuranosylpyridin-4-one-3- carboxamide (PCR) is one of several novel nucleosides isolated in our laboratory from the urine of chronic myelogenous leukemia patients. Its crystal structure and conformation were studied to complete its characterization. This nucleoside exhibits an anti (XCN = 66.9°) conformation across the glycosidic bond, a rare pucker of the ribose ring, C(4′)exo-C(3′)endo (4T3), and g+ across the C(4′)-C(5′) bond. The amino group of the carboxamide is proximal to and hydrogen bonded intramolecularly to 0(4). Nuclear magnetic resonance studies show that the intramolecular hydrogen bond is present in the solution state also, but the solution conformation of the furanose ring is not the same as that observed in the solid.

Isolation and Characterization of an Unusual Nucleoside, 1-α-D-Ribofuranosyl-4-pyridone-3-carboxamide, from the Urines of Normal Human Individuals and Leukemic Patients

Abstract A novel modified nucleoside, 1-α-D-Ribofuranosyl-4-pyridone-3-carboxamide, has been isolated from the urines of one normal human individual and two CML patients. The structure was assigned on the basis of UV, NMR and mass spectral data and confirmed by comparison with an authentic sample synthesized in our laboratory. This constitutes the first example of the occurrence of a nucleoside with an α-riboside linkage in human urine.

Separation of naturally occurring 3′, 5′-cyclic ribonucleotides using high pressure liquid chromatography

Abstract A simple and fairly rapid procedure is described for separation of a mixture of five 3′, 5′-cyclic ribonucleotides. The separation was achieved by high pressure liquid chromatography on a Vydac pellicular anion exchange column using a linear gradient of 0.5 to 1.0 m acetic acid as the eluting solvent.

Metabolism of 1-methyladenosine

1-[methyl-8-14C] Adenosine was synthesized and its metabolic fate was determined in intact rat. It was found that approximately 57% of 1-[methyl-8-14C] adenosine administered iv was excreted unchanged in the urine and 33% of the excreted radioactivity in the urine was associated with the major metabolite 1-methyl-hypoxanthine and about 4.5% was associated with 1-methylinosine. Very little adenosine or N6-methyladenosine was formed. It is concluded that 1-methyladenosine is initially deaminated by adenosine deaminase to 1-methylinosine which is then cleaved by nucleoside phosphorylase to 1-methylhypoxanthine.

Synthesis and Biological Activity of 6-Hydroxyguanidino-and 6-Hydroxyureidopurine And Their Ribonucleosides

Abstract N 6 −(1-hydroxyguanidino)purine IIa, and its 9-β-D-ribonucleoside derivative IIb were prepared by reacting at room temperature 6-hydroxyadenine Ia and 6-hydroxyadenosine Ib, with 1-guanyl-3,5-dimethylpyrazole nitrate in DMF. Refluxing IIa and IIb in 95% ethanol gave N6−(1-hydroxyureido)purine and its ribonucleoside derivative respectively; the latter compound was also obtained by refluxing Ib with 1-guanyl-3,5-dimethylpyrazole nitrate in ethanol. The two base analogs were inactive against L1210 cells in vitro, but the nucleoside derivatives inhibited the growth of these cells by 50% at 5 × 10 -6 and 6 × 10−7 M respectively. Compound IIb, at 200 mg/kg/day × 5, increased the life span of L1210-bearing DBA/2N mice by 57%. Cytofluorometric determinations showed that IIb inhibited cell growth in the G2 phase of the cell cycle. also found to inhibit adenosine deaminase activity with a Ki = 3.47 μM.

Chapter 5 Isolation and Characterization of Modified Nucleo-Sides From human Urine

Publisher Summary Mammalian urine contains more than 500 substances with molecular weights of less than one thousand. Many of these compounds are derived from metabolism of nucleic acids, proteins, carbohydrates, lipids, steroids, fatty acids, vitamins, cofactors and growth factors. While many of the urinary nucleosides and bases are derived from the turnover or degradation of nucleic acids, such as tRNA, rRNA, mRNA and DNA, some of the nucleosides are derived from anabolic nucleotide intermediates and cofactors involved in biosynthesis of nucleic acids as well as other macro-molecules. In a method described in the chapter, a modified heavy duty reagent bottle serves as a reservoir. The stopcock at the top of the column is connected by polyethylene tubing to a reservoir. The top of the reservoir is adapted to connect to a nitrogen tank or to a pump to pressurize the system for sufficient flow rate (5 ml/min). The system is made entirely from heavy walled glass and teflon components.