RESUMEN
We recently reported N4-substituted 3-methylcytidine-5'-α,ß-methylenediphosphates as CD73 inhibitors, potentially useful in cancer immunotherapy. We now expand the structure-activity relationship of pyrimidine nucleotides as human CD73 inhibitors. 4-Chloro (MRS4598 16; Ki = 0.673 nM) and 4-iodo (MRS4620 18; Ki = 0.436 nM) substitution of the N4-benzyloxy group decreased Ki by â¼20-fold. Primary alkylamine derivatives coupled through a p-amido group with a varying methylene chain length (24 and 25) were functionalized congeners, for subsequent conjugation to carrier or reporter moieties. X-ray structures of hCD73 with two inhibitors indicated a ribose ring conformational adaptation, and the benzyloxyimino group (E configuration) binds to the same region (between the C-terminal and N-terminal domains) as N4-benzyl groups in adenine inhibitors. Molecular dynamics identified stabilizing interactions and predicted conformational diversity. Thus, by N4-benzyloxy substitution, we have greatly enhanced the inhibitory potency and added functionality enabling molecular probes. Their potential as anticancer drugs was confirmed by blocking CD73 activity in tumor tissues in situ.
Asunto(s)
5'-Nucleotidasa/antagonistas & inhibidores , Nucleótidos de Citosina/farmacología , Difosfonatos/farmacología , Inhibidores Enzimáticos/farmacología , 5'-Nucleotidasa/metabolismo , Adulto , Nucleótidos de Citosina/síntesis química , Nucleótidos de Citosina/metabolismo , Difosfonatos/síntesis química , Difosfonatos/metabolismo , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/metabolismo , Proteínas Ligadas a GPI/antagonistas & inhibidores , Proteínas Ligadas a GPI/metabolismo , Humanos , Masculino , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Estructura Molecular , Neoplasias/enzimología , Tonsila Palatina/enzimología , Unión Proteica , Relación Estructura-ActividadRESUMEN
We present a facile method to phosphorylate small amounts of nucleosides (0.05 mumol) into mixtures of their 5'-mono-, di-, and triphosphates in a one-pot reaction. The nucleosides were first converted into their dichlorophosphates using a large excess (15-18 equivalents) of phosphorous oxychloride in trimethylphosphate. The large excess resulted in good dichlorophosphate yields (46-76%) for the four nucleosides tested. Upon the addition of tributylammonium-phosphate with additional tributylamine (20 equivalents both), the dichlorophosphate was converted into a mixture containing equal amounts of the mono-, di-, and triphosphate. The presented method was successfully applied to synthesize mixtures of stable isotope labeled nucleotides, which can be used as internal standards in quantitative mass spectrometric assays.
Asunto(s)
Adenosina Monofosfato/análogos & derivados , Química Orgánica/métodos , Nucleótidos de Citosina/síntesis química , Nucleótidos/síntesis química , Adenosina Monofosfato/síntesis química , Adenosina Monofosfato/química , Tampones (Química) , Cromatografía Líquida de Alta Presión , Nucleótidos de Citosina/química , Hidrólisis , Indicadores y Reactivos , Espectrometría de Masas , Nucleótidos/química , Compuestos de Fósforo/químicaRESUMEN
Nucleoside phosphoesters (nucleotides) have crucial roles in a large variety of biological processes including nucleic acid biosynthesis and their corresponding analogues are extensively used as biological tools. Herein, we describe a new and efficient synthetic procedure involving polyethylene glycol (PEG) as soluble support and regioselective mono-, di-, and triphosphorylation steps. Applied to natural and synthetic cytosine containing nucleosides, this methodology allowed the preparation of various phosphorylated forms in high yields and good purity.
Asunto(s)
Nucleótidos de Citosina/síntesis química , Polietilenglicoles/química , Métodos , Nucleótidos/síntesis química , Fosforilación , SolubilidadRESUMEN
The molybdenum-containing iron-sulfur flavoprotein CO dehydrogenase is expressed in a catalytically fully competent form during heterotrophic growth of the aerobic bacterium Hydrogenophaga pseudoflava with pyruvate plus CO. We have adopted these conditions for studying the effect of molybdate (Mo) and tungstate (W) on the biosynthesis of CO dehydrogenase and its molybdopterin (MPT) cytosine-dinucleotide-(MCD)-type molybdenum cofactor. W was taken up by the Mo transport system and, therefore, interfered with Mo transport in an antagonistic way. Depletion of Mo from the growth medium as well as inclusion of excess W both resulted in the absence of intracellular Mo and led to the biosynthesis of CO dehydrogenase species of proper L2M2S2 subunit structure that carried the two 2Fe:2S type-I and type-II centers and two FAD molecules. EPR, ultraviolet/visible and CD spectroscopies established the full functionality of the cofactors. Due to the absence of the Mo-MCD cofactor, the enzyme species were catalytically inactive. Unexpectedly, the following cytidine nucleotides were present in inactive CO dehydrogenase: CDP, dCDP, CMP, dCMP, CTP or dCTP. The sum of cytidine nucleotides was two/mol enzyme. The binding specificities of inactive CO dehydrogenase for cytidine nucleotides (oxy > deoxy; diphosphate > monophosphate > triphosphate), and the absence of MPT suggest that, in active CO dehydrogenase, the cytidine diphosphate moiety of Mo-MCD provides the strongest interactions with the protein and determines the specificity for the type of nucleotide. In H. pseudoflava, the biosynthesis of MPT (identified as form A) was independent of Mo. Mo was, however, strictly required for the conversion of MPT to MCD (identified as form-A-CMP) as well as the insertion of Mo-MCD into CO dehydrogenase. These data support a model for the involvement of Mo in the biosynthesis of the Mo-MCD cofactor and of fully functional CO dehydrogenase in which the synthesis and insertion of Mo-MCD require Mo, and protein synthesis including integration of the FeS-centers and FAD are independent of Mo.
Asunto(s)
Aldehído Oxidorreductasas/biosíntesis , Coenzimas , Nucleótidos de Citosina/síntesis química , Molibdeno/farmacología , Complejos Multienzimáticos/biosíntesis , Pseudomonas/metabolismo , Pterinas/síntesis química , Compuestos de Tungsteno/farmacología , Aldehído Oxidorreductasas/análisis , Aldehído Oxidorreductasas/química , Dicroismo Circular , Metaloproteínas/metabolismo , Cofactores de Molibdeno , Complejos Multienzimáticos/análisis , Complejos Multienzimáticos/química , Oxidación-Reducción , Pteridinas/metabolismoRESUMEN
The acyclic nucleotide analogue (S)-1-[3-hydroxy-2-(phosphonylmethoxy)propyl] cytosine (2, HPMPC) was prepared on a multigram scale in 18% overall yield starting from (R)-2,3-O-isopropylideneglycerol. The key step in the nine-step synthetic route is coupling of cytosine with the side-chain derivative 8 which bears a protected phosphonylmethyl ether group. In vitro data showed that HPMPC has good activity against herpes simplex virus types 1 and 2, although it was 10-fold less potent than acyclovir [AVC, 9-[(2-hydroxyethoxy)methyl]guanine]. By comparison, HPMPC exhibited greater activity than ACV against a thymidine kinase deficient strain of HSV 1 and was more potent than ganciclovir [DHPG, 9-[(1,3-dihydroxy-2-propoxy)methyl]guanine] against human cytomegalovirus. In vivo, HPMPC showed exceptional potency against HSV 1 systemic infection in mice, having an ED50 of 0.1 mg/kg per day (ip) compared with 50 mg/kg per day for ACV. HPMPC was also more efficacious than ACV in the topical treatment of HSV 1 induced cutaneous lesions in guinea pigs.
Asunto(s)
Antivirales/síntesis química , Nucleótidos de Citosina/síntesis química , Citosina/análogos & derivados , Organofosfonatos , Compuestos Organofosforados/síntesis química , Animales , Fenómenos Químicos , Química , Cidofovir , Citomegalovirus/efectos de los fármacos , Citosina/síntesis química , Citosina/farmacología , Nucleótidos de Citosina/farmacología , Femenino , Cobayas , Humanos , Ratones , Compuestos Organofosforados/farmacología , Simplexvirus/efectos de los fármacos , Células VeroRESUMEN
Methyl 2,3-O-isopropylidene-D-ribofuranoside (1) was converted to 1-O-acetyl-5-bromo-5-deoxy-2,3-di-O-benzoyl-D-ribofuranose (6) in five steps with good yield. The Arbuzov condensation of compound 6 with triethyl phosphite resulted in the synthesis of 1-O-acetyl-2,3-di-O-benzoyl-5-deoxy-5-(diethoxyphosphinyl)-D-ribofuranos e (7). Compound 7 was used for direct glycosylation of both purine and pyrimidine bases. The glycosylation was accomplished with the dry silylated heterocyclic base in the presence of trimethylsilyl triflate. Deblocking of the glycosylation products gave exclusively the beta anomer of the 5'-phosphonate analogues of 9-[5'-deoxy-5'-(dihydroxyphosphinyl)-beta-D-ribofuranosyl]adenine (13), 9-[5'-deoxy-5'-(dihydroxyphosphinyl)-beta-D-ribofuranosyl]guanosin e (16), 9-[5'-deoxy-5'-(dihydroxyphosphinyl)-beta-D-ribofuranosyl]hypoxant hine (17), and 9-[5'-deoxy-5'-(dihydroxyphosphinyl)-beta-D-ribofuranosyl]cytosine (15), described here for the first time. The target compounds as well as their intermediates showed no in vitro antiviral or antitumor activity, although phosphorylation of 15 and 16 to di- and triphosphate analogues was demonstrated with use of isolated cellular enzymes.
Asunto(s)
Adenosina Monofosfato , Citidina Monofosfato , Nucleótidos de Citosina , Nucleótidos de Guanina , Guanosina Monofosfato , Inosina Monofosfato , Nucleótidos de Inosina , Neoplasias/tratamiento farmacológico , Virus/efectos de los fármacos , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/síntesis química , Adenosina Monofosfato/farmacología , Adenosina Monofosfato/uso terapéutico , Animales , Fenómenos Químicos , Química , Neoplasias del Colon/tratamiento farmacológico , Citidina Monofosfato/análogos & derivados , Citidina Monofosfato/síntesis química , Citidina Monofosfato/farmacología , Citidina Monofosfato/uso terapéutico , Nucleótidos de Citosina/análogos & derivados , Nucleótidos de Citosina/síntesis química , Nucleótidos de Citosina/farmacología , Nucleótidos de Citosina/uso terapéutico , Nucleótidos de Guanina/análogos & derivados , Nucleótidos de Guanina/síntesis química , Nucleótidos de Guanina/farmacología , Nucleótidos de Guanina/uso terapéutico , Guanosina Monofosfato/análogos & derivados , Guanosina Monofosfato/síntesis química , Guanosina Monofosfato/farmacología , Guanosina Monofosfato/uso terapéutico , Humanos , Inosina Monofosfato/análogos & derivados , Inosina Monofosfato/síntesis química , Inosina Monofosfato/farmacología , Inosina Monofosfato/uso terapéutico , Nucleótidos de Inosina/análogos & derivados , Nucleótidos de Inosina/síntesis química , Nucleótidos de Inosina/farmacología , Nucleótidos de Inosina/uso terapéutico , Leucemia/tratamiento farmacológico , Leucemia L1210/tratamiento farmacológico , Espectroscopía de Resonancia Magnética , Ratones , Estructura Molecular , Fosforilación , Espectrofotometría Ultravioleta , Relación Estructura-Actividad , Células Tumorales CultivadasRESUMEN
A series of 5-alkylcytidines and their 5'-monophosphates and cyclic 3',5'-monophosphates have been synthesized and evaluated for antiviral and antitumor activity. The 5-alkyl cyclic nucleotides were not cytostatic (ID50 greater than 200 micrograms/mL) against leukemia L1210 cells and a deoxycytidine kinase-deficient subline thereof. Certain of the corresponding nucleosides and their 5'-monophosphates did show activity within the range of 35-162 micrograms/mL, as did the unsubstituted cytidine cyclic 3',5'-monophosphate. No antiviral activity was found for any of the compounds at 400 micrograms/mL. A drug design rationale for utilization of 5-alkylcytidines based on their potential conversion to biologically active 5-alkyl-2'-deoxyuridines is not supported by these experimental findings.
Asunto(s)
Antineoplásicos/síntesis química , Antivirales/síntesis química , CMP Cíclico/síntesis química , Nucleótidos de Citosina/síntesis química , Animales , Fenómenos Químicos , Química , CMP Cíclico/análogos & derivados , CMP Cíclico/farmacología , Leucemia L1210/tratamiento farmacológico , Proteínas Quinasas/metabolismo , Conejos , Simplexvirus/efectos de los fármacos , Relación Estructura-Actividad , Células Tumorales Cultivadas , Virus Vaccinia/efectos de los fármacos , Virus de la Estomatitis Vesicular Indiana/efectos de los fármacosRESUMEN
A new approach to oligoribonucleotide synthesis has been developed by use of the p-nitrophenylethylsulfonyl group as a new versatile sugar protecting group. The synthesis of 3'-5'- and 2'-5'-cydidylyl-cytidine is performed in high yield.
Asunto(s)
Citidina Monofosfato/síntesis química , Citidina/análogos & derivados , Nucleótidos de Citosina/síntesis química , Fosfatos de Dinucleósidos , Oligorribonucleótidos , Sulfonas , Citidina/síntesis química , Citidina Monofosfato/análogos & derivados , Indicadores y Reactivos , NitrobencenosRESUMEN
The oligonucleotides C(pC)n, n = 4, 5, 6, 7, are efficient templates for the oligomerization of guanosine-5'-phospho-2-methylimidazole (2-MeImpG). They yield oligomeric products that are substantially less regiospecific than those obtained on polycytidylate [poly(C)]. The overall distributions of products obtained on oligo(C)s are generally similar to those of products obtained on oligodeoxycytidylates [oligo(dC)s], but there are substantial differences in the ratios of isomers. The 3'-5'-linked dinucleoside monophosphate GpG efficiently initiates oligomer formation with 2-MeImpG on oligo(C) templates. The pattern of products obtained by chain extension parallels closely that of products obtained directly from 2-MeImpG, except that the former products lack the 5'-terminal phosphate group.
Asunto(s)
Nucleótidos de Citosina/síntesis química , Oligorribonucleótidos/síntesis química , Poli C , Polirribonucleótidos , Indicadores y Reactivos , Cinética , Moldes GenéticosRESUMEN
A series of 1-beta-ribofuranosyl-5-halocytosine cyclic 3',5'-monophosphates (1-4) has been prepared. Direct halogenation of cytidine 3',5'-monophosphate (cCMP) yielded the Cl, Br, and I compounds while 5-F-cCMP (1) was obtained on cyclization of the 5'-monophosphate. On in vitro testing of 1-4 against L1210 and P388 leukemias, only 1 showed significant low-level activity (ID50 = 3.1 X 10(-4) mmol/L). Derivatives 2-4 were inactive at 10(-1) mmol/L and also proved to have low viral ratings against a series of RNA and DNA virus strains in vitro. By contrast the 5-F-cCMP showed moderate activity against VV, HSV-1, and HSV-2 strains (VR = 0.6-0.9). Both 5-fluorocytidine and 5-fluorocytidine 5'-monophosphate had marked antiviral activity (VR = 1.0-2.1) with the above viruses as well as with parainfluenza virus type 3. The nucleoside and nucleotide also were more active than 5-F-cCMP against L1210 and P388 cells. However, comparison of the cytotoxicities and antiviral ED50 values of 5-F-cCMP, 5-fluorocytidine 5'-monophosphate, and 5-fluorocytidine suggests a potential therapeutic advantage for 5-F-cCMP. Possible rationales for these activities are discussed in terms of 5-F-cCMP and the corresponding 5'-monophosphate as potential prodrugs and as sources, following enzymatic deamination, of cytotoxic 5-fluorouridine or its 5'-monophosphate.
Asunto(s)
Antineoplásicos/síntesis química , Antivirales/síntesis química , CMP Cíclico/síntesis química , Nucleótidos de Citosina/síntesis química , Animales , Antineoplásicos/farmacología , Antivirales/farmacología , CMP Cíclico/análogos & derivados , CMP Cíclico/farmacología , Leucemia Experimental/tratamiento farmacológico , Ratones , Proteínas Quinasas/análisisRESUMEN
Chemically synthesized 5-fluoro-2'-deoxyuridine 5'-triphosphate and 5-fluoro-2'-deoxycytidine 5'-triphosphate were used efficiently as substitutes for DNA synthesis catalyzed by DNA polymerases alpha or beta from calf thymus. 5-fluoro-2'-deoxyuridine 5'-triphosphate and 5'-fluoro-2'-deoxycytidine 5'-triphosphate were incorporated into DNA in place of deoxythymidine 5'-triphosphate and deoxycytidine 5'-triphosphate, respectively. The incorporated pyrimidine analogs supported further elongation of DNA. The apparent Km's for 5-fluorodeoxyuridine 5'-triphosphate in the reaction of DNA polymerases alpha and beta were 4.3 and 15.4 microM, while those of 5-fluorodeoxycytidine 5'-triphosphate with DNA polymerases alpha and beta were 7.7 and 8.8 microM, respectively, which are comparable to Km's for natural substrates. These results suggest the new possibility that the fluorinated pyrimidines are incorporated into DNA via their triphosphate forms to exhibit their cytostatic actions.
Asunto(s)
Nucleótidos de Citosina/metabolismo , ADN Polimerasa II/metabolismo , ADN Polimerasa I/metabolismo , ADN Polimerasa Dirigida por ADN/metabolismo , ADN/biosíntesis , Nucleótidos de Desoxiuracil/metabolismo , Fluorodesoxiuridilato/metabolismo , Animales , Bovinos , Nucleótidos de Citosina/síntesis química , Fluorodesoxiuridilato/síntesis químicaRESUMEN
T4 RNA ligase (EC 6.5.1.3) has been used to link cytidine 3',5'-[5'-32P]bisphosphate or unlabelled cytidine 3',5'-bisphosphate (pCp) covalently to the 3'-OH of individual components of 5'-triphospho-oligo[(2'-5')adenylyl]adenosine [ppp(A2'p)nA with n = 2 or 3] and adenylyl(2'-5')adenylyl(2'-5')adenosine [(A2'p)2A] to yield 5'-triphospho-oligo[(2'-5')adenylyl]adenylyl(3'-5')cytidine 3'-phosphate [ppp(A2'p)nApCp with n = 2 or 3] and adenylyl(2'-5')adenylyl(2'-5')adenylyl(3'-5')cytidine 3'-phosphate (A2'p)2ApCp], respectively. The radioactive products isolated by high-performance liquid chromatography had specific activities greater than 10(6) Ci/mol. These products were found to be effective probes for use in radiobinding and radioimmune assays for ppp(A2'p)nA and (A2'p)nA [M. Knight et al. (1980) Nature 288, 189-192]. ppp(A2'p)nA is unstable in cell-free systems and in intact cells. ppp(A2'p)nApCp, however, was found to be much more stable than ppp(A2'p)nA in extracts of rabbit reticulocytes or Ehrlich ascites tumour cells. (A2'p)2Ap, (A2'p)2ApC (reticulocyte only) or (A2'p)2ApCp were also more stable than unmodified (A2'p)2A in these systems. The results are consistent with a specific degradation pathway for ppp(A2'p)nA which proceeds from the 3' terminus. ppp(A2'p)3ApCp activated the ppp(A2'p)nA-dependent RNase and inhibited protein synthesis in a reticulocyte cell-free system at least as well as unmodified tetramer ppp(A2'p)3A, suggesting that an unmodified 3' terminus is not required for full activity in this system. In extracts from mouse Ehrlich ascites tumour or L-cells, however, ppp(A2'p)nApCp was greater than or equal to 30 fold less active (if directly active at all).
Asunto(s)
Nucleótidos de Adenina/síntesis química , Oligonucleótidos/síntesis química , Oligorribonucleótidos/síntesis química , Nucleótidos de Adenina/farmacología , Animales , Carcinoma de Ehrlich/metabolismo , Sistema Libre de Células , Nucleótidos de Citosina/síntesis química , Nucleótidos de Citosina/farmacología , Estabilidad de Medicamentos , Técnicas In Vitro , Marcaje Isotópico , Oligorribonucleótidos/farmacología , Radioisótopos de Fósforo , Biosíntesis de Proteínas , Conejos , Reticulocitos/metabolismoRESUMEN
Syntheses of five pairs of cytosine and 5-fluorocytosinexylofuranosyl nucleosides in which the 3'-hydroxyl group is replaced by Cl, Br, OMs, or OTs are described. Those xylosyl nucleosides with a good leaving group at the 3' position exhibit good inhibitory activity against L5178Y and P815 mouse leukemic cells in vitro at rather low concentrations, and like that of ara-C this cytotoxicity is reversed by 2'-deoxycytidine but not by thymidine. Xylosylcytosines are not active against ara-C resistant lines of L5178Y and P815 cells; however, the corresponding 5-fluorocytosine analogues exhibit significant cytotoxicity against these ara-C resistant leukemic cell lines, and this activity is reversed by thmidine but not by deoxycytidine. These data support the "double-barreled" masked precursor hypothesis in that xylosyl-5-fluorocytosines substituted at the 3' position by a good leaving group exhibit activity akin to that of ara-C in the ara-C sensitive lines, while these nucleosides act as 5-fluoropyrimidines in the ara-C resistant lines.
Asunto(s)
Antineoplásicos/síntesis química , Nucleótidos de Citosina/síntesis química , Animales , Línea Celular , Nucleótidos de Citosina/metabolismo , Nucleótidos de Citosina/farmacología , Leucemia Experimental/tratamiento farmacológico , Ratones , Relación Estructura-ActividadRESUMEN
A simple chemical procedure for the preparation of four common ribonucleoside 5-gamma-[32P]triphosphates of high specific activity (up to 10 Ci/mmole) based on the condensation of orthophosphoric acid with the corresponding nucleoside 5-diphosphate in the presence of ethyl chloroformate as well as the methods of purification and identification of the products are described.
Asunto(s)
Adenosina Trifosfato/síntesis química , Citidina Trifosfato/síntesis química , Nucleótidos de Citosina/síntesis química , Guanosina Trifosfato/síntesis química , Nucleótidos de Uracilo/síntesis química , Uridina Trifosfato/síntesis química , Adenosina Trifosfato/análisis , Citidina Trifosfato/análisis , Guanosina Trifosfato/análisis , Marcaje Isotópico , Métodos , Radioisótopos de Fósforo , Uridina Trifosfato/análisisRESUMEN
Mild, acidic hydrolysis of 3-O-benzoyl-1,2,:5,6-di-O-isopropylidene-alpha-D-allofuranose gave a diol that was selectively benzoylated at O-6 in high yield by intermediate conversion to the stannylene derivative. The 3,6-dibenzoate was converted to the 5-O-tosyl derivative and thence to a mixture of iodides, which were reduced with tributylstannane to 3,6-di-O-benzoyl-1,2-O-isopropylidene-alpha-D-ribo-hexofuranose (6). Acetolysis gave an anomeric mixture of diacetates, which, when treated with N-acetylbis(trimethylsilyl)cytosine gave the protected nucleoside, which was deprotected to free "homocytidine", 1-(5-deoxy-beta-D-ribo-hexofuranosyl)cytosine (11), by alklaine methanolysis. This was N-acetylated and then treated with acetone to give a protected nucleoside, which was labelled by oxidation to the aldehyde, reduction with sodium borotritide, and deprotection. Acidic methanolysis of 6 gave a mixture of methyl 2,6- and 3,6-di-O-benzoylfuranosides, the hydroxyl groups of which were treated by the tetrachloromethane-triphenylphosphine reagent to give the 2-chloro-2-deoxy (21) and 3-chloro-3-deoxy derivatives. Reduction of 21 gave methyl 3,6-di-O-benzoyl-2,5-dideoxy-D-erythro-furanoside, further transformed in 1-(2,5-dideoxy-beta-D-erythro-hexofuranosyl)cytosine mixed with the alpha anomer. Phosphates and diphosphates of the nucleosides were prepared by extensions of known methods. The phosphate and the diphosphate of 11 act neither as substrates nor as inhibitors of a ribonucleotide-reductase from rat asicites tumor.
Asunto(s)
Nucleótidos de Citosina/síntesis química , Citosina/análogos & derivados , Desoxiazúcares/síntesis química , Ribonucleótido Reductasas/metabolismo , Animales , Citosina/síntesis química , Neoplasias Hepáticas Experimentales/enzimología , Espectroscopía de Resonancia Magnética , Métodos , Ratas , Especificidad por SustratoRESUMEN
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 formation of the title compound. Structure and reactivity of this thioanalog differ substantially from 2':3'-CMP.
Asunto(s)
Nucleótidos de Citosina/síntesis química , Tionucleótidos/síntesis química , Hidrólisis , Relación Estructura-ActividadAsunto(s)
Nucleótidos Cíclicos/síntesis química , Nucleótidos de Adenina/síntesis química , Fosfatasa Alcalina , Animales , Bovinos , Cromatografía por Intercambio Iónico , Cromatografía en Capa Delgada , Nucleótidos de Citosina/síntesis química , Escherichia coli/enzimología , Nucleótidos de Guanina/síntesis química , Páncreas/enzimología , Ribonucleasas , Nucleótidos de Uracilo/síntesis químicaRESUMEN
The synthesis of 2'-O-methylcytidylyl (3'-5')cytidine by the triester method using as protecting groups, 2,2,2-trichloroethyl for phosphate hydroxyl group, p-chlorophenyoxyacetyl for 5-hydroxyl group, methoxymethylidene for 2',3'-cis-diol system, and benzoyl for the exo-amino group of cytidine is presented. The obtained product was characterised by UV, electrophoresis, chromatography and an enzymatic digestion.