D-Guanosine

Which of the following compounds is different from the others (a) GMP, (b) deoxyguanosine monophosphate, (c) guanylic acid, (d) guanosine 5 -phosphate ... 

Figure 20.3 Separation of nucleotides and nucleosides on a silica gel layer. Compounds E, adenosine H, guanosine F, uridine G, cytidine A, adeno-sine-5-monophosphate B, uridine-5-monophosphate C, cystidine-5-mono-phosphate D, guanosine-5-monophosphate. [Reproduced with the permission of John Wiley and Sons, Inc., from Sleckman et al. (1985).]...

The results of the separation are shown in Figure 20.3. The approximate Rp values are as follows D, guanosine-5-monophosphate, 0.09 C, cystidine-5-monophos-phate, 0.13 B, uridine-5-monophosphate, 0.23 A, adenosine-5-monophosphate, 0.25 G, cytidine, 0.44 F, uridine, 0.48 H, guanosine, 0.53 E, adenosine, 0.63. This system should allow the separation of six of the eight compounds. Some overlap will be noted between (A) adenosine-5-monophosphate and (B) uridine-5 -monophosphate. 

These organisms have been used frequently in the elucidation of the biosynthetic pathway (37,38). The mechanism of riboflavin biosynthesis has formally been deduced from data derived from several experiments involving a variety of organisms (Fig. 5). Included are conversion of a purine such as guanosine triphosphate (GTP) to 6,7-dimethyl-8-D-ribityUuma2ine (16) (39), and the conversion of (16) to (1). This concept of the biochemical formation of riboflavin was verified in vitro under nonen2ymatic conditions (40) (see Microbial transformations). 

Guanine, 9-/3-D-ribofuranosyl-, 5, 536 Guanine, 6-thio-tautomerism, 5, 509 toxicity, 1, 141 Guanine, 8-trifluoromethyl-synthesis, 5, 574 Guanines, thio-synthesis, 5, 572 Guanosine arylation, 5, 538 dipole moment, 5, 522 free radical alkylation, 5, 543 hydrobromide... 

The 2 -C-methyl-substituted ribonucleosides 2 -C-methyladenosine and -guanosine were also found to inhibit the replication of flaviviruses other than HCV, such as bovine viral diarrhea virus (BVDV), yellow fever virus, and West Nile virus (Mighaccio et al. 2003). Other 2 -C-methylribonucleosides such as P-D-2 -deoxy-2 -lluoro-2 -C-methylcytidine (PSl-6130), however, showed little if any activity against BVDV, West Nile virus, or yellow fever virus (Stuyver et al. 2006). 

Weber, L. A., Hickey, E.D., Nuss, D.L. Bayloni, C. (1977). 5 -terminal 7-methyl-guanosine and messenger RNA function influence of potassium concentration on translation in vitro. Journal of Biological Chemistry, 252, 4007-10. 

Fig. 5.22 Thymidine (A), guanosine (B) and some nucleoside analogues (C-J). C, idoxuridine D, cytarabine E, ribavirin F, zidovudine (AZT) G, dideoxycytidine (DDC) H, dideoxyinosine (DDI) I, acyclovir J, ganciclovir.

Schneider, F Lutun, P Couchot, A., Bilbault, P., and Tempe, J, D., Plasma cyclic guanosine 3 -5 monophosphate concentrations and low vascular resistance in human septic shock. Intensive Care Med. 19,99-104(1993). 

Figure 11.4 Analysis of in vitro synthesized RNAs. 32P-Radiolabeled RNAs (48 nucleotides) capped with m7Gp3G (A and C) or m27,3 °Gp3G (B and D) were digested with either RNase T2 (A and C) or RNase T2 plus tobacco acid pyrophosphatase (TAP) (B and D) followed by anion-exchange HPLC on a Partisil 10SAX/25 column as described in the text. Fractions of 1 ml were collected, and the Cerenkov radiation was determined. The elution times of the following standard compounds, detected by ultraviolet (UV) absorption, are indicated with arrows 3,-CMP (Cp), S UMP (Up), 37-AMP (Ap), 3 -GMP (Gp), 3, 5 -m7GDP (pm7Gp), 3, 5 -GDP (pGp), 5 -GDP (p2G), 5 -GTP (p3G), and guanosine-SCtetraphosphate (P4G).

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