115479-39-5

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A series of nicotinamide hypoxanthine 5′-dinucleotide (NHD +) analogues modified at C-8 (2-5) and 7-deaza-NHD+ were synthesized, and cyclization in the presence of Aplysia ADP-ribosyl cyclase was studied. All 8-substituted NHD+ analogues were converted into their N1-cyclic forms by the enzyme, while in contrast, 7-deaza-NHD+ 17 was hydrolyzed into 7-deazainosine 5′-diphosphoribose (7-deaza-IDPR) 25. Correlations are made showing that the conformation of the NHD+ substrate is the key to successful cyclization. The pharmacological activities of these novel cIDPR derivatives were evaluated in both permeabilized and intact Jurkat T-lymphocytes. The results show that in permeabilized cells both 8-iodo 1g and 8-N3-N1-cIDPR 1d have an activity comparable to that of cADPR, while 8-iodo 1g and 8-phenyl-N1-cIDPR 1c have a small but significant effect in intact cells and can therefore be regarded as membrane-permeant; thus, cIDPR derivatives are emerging as important novel biological tools to study cADPR-mediated Ca2+ release in T-cells.

Disclosed are cyclic-di-nucleotide cGAMP analogs, methods of synthesizing the compounds, pharmaceutical compositions comprising the compounds thereof, and use of compounds and compositions in medical therapy.

Elucidation of dynamic interactions between RNA and proteins is essential for understanding the biological processes regulated by RNA, such as RNA interference (RNAi). In this study, the logical chemical probes, comprising 7-bromo-7-deazaadenosine (Br7C7A) and 3-bromo-3-deazaadenosine (Br3C3A), to investigate small interfering RNA (siRNA)-RNAi related protein interactions, were developed. The bromo substituents of Br7C7A and Br3C3A are expected to be located in the major and the minor grooves, respectively, and to act as a steric hindrance in each groove when these chemical probes are incorporated into siRNAs. A comprehensive investigation using siRNAs containing these chemical probes revealed that (i) Br3C3A(s) at the 5′-end of the passenger strand enhanced their RNAi activity, and (ii) the direction of RISC assembly is determined by the interaction between Argonaute2, which is the main component of RISC, and siRNA in the minor groove near the 5′-end of the passenger strand. Utilization of these chemical probes enables the investigation of the dynamic interactions between RNA and proteins.

Compounds of the general formula (I): processes for the preparation of these compounds, compositions containing these compounds, and the uses of these compounds.

The present invention relates to substituted 7-deazapurine compounds. The present invention also relates to pharmaceutical compositions containing these compounds and methods of treating disorders in which DOT1-mediated protein methylation plays a part, such as cancer, by administering these compounds and pharmaceutical compositions to subjects in need thereof.

A series of novel 7-deazapurine ribonucleosides bearing an alkyl, aryl, or hetaryl group in position 6 and H, F, or Cl atom in position 7 has been prepared either by Pd-catalyzed cross-coupling reactions of the corresponding protected 6-chloro-(7-halogenated-)7-deazapurine ribonucleosides with alkyl- or (het)-arylorganometallics followed by deprotection, or by single-step aqueous phase cross-coupling reactions of unprotected 6-chloro-(7-halogenated-)7- deazapurine ribonucleosides with (het)arylboronic acids. Significant cytostatic effect was detected with a substantial proportion of the prepared compounds. The most potent were 7-H or 7-F derivatives of 6-furyl- or 6-thienyl-7-deazapurines displaying cytostatic activity in multiple cancer cell lines with a geometric mean of 50% growth inhibition concentration ranging from 16 to 96 nM, a potency comparable to or better than that of the nucleoside analogue clofarabine. Intracellular phosphorylation to mono- and triphosphates and the inhibition of total RNA synthesis was demonstrated in preliminary study of metabolism and mechanism of action studies. 2009 American Chemical Society.

Several 7-deaza-6-benzylthioinosine analogues with varied substituents on aromatic ring were synthesized and evaluated against Toxoplasma gondii adenosine kinase (EC.2.7.1.20). Structure-activity relationships indicated that the nitrogen atom at the 7-position does not appear to be a critical structural requirement. Molecular modeling reveals that the 7-deazapurine motif provided flexibility to the 6-benzylthio group as a result of the absence of H-bonding between N7 and Thr140. This flexibility allowed better fitting of the 6-benzylthio group into the hydrophobic pocket of the enzyme at the 6-position. In general, single substitutions at the para or meta position enhanced binding. On the other hand, single substitutions at the ortho position led to the loss of binding affinity. The most potent compounds, 7-deaza-p-cyano-6- benzylthioinosine (IC50 = 5.3 μM) and 7-deaza-p-methoxy-6- benzylthioinosine (IC50 = 4.6 μM), were evaluated in cell culture to delineate their selective toxicity.

A simple synthesis of tubercidin, 7-deazaguanosine and 2'-deoxy-7-deazaguanosine has been accomplished using the sodium salt glycosylation procedure. Reaction of the sodium salt of 4-chloro- and 2-amino-4-chloro-pyrrolo[2,3-d]pyrimidine, 3 and 4, respectively, with 1-chloro-2,3-O-isopropylidene,5-O-(t-butyl)dimethylsilyl-α-D-ribofur nose gave the corresponding protected nucleosides 6 and 7 with β-anomeric configuration. Deprotection of 6 provided 8, which on heating with methanolic ammonia gave tubercidin in excellent yield. Functional group transformation of 7, followed by deisopropylidenation gave 2-aminotubercidin and 2-amino-7-β-ribofuranosylpyrrolo[2,3-d]pyrimidine-4(3H)-thione. Treatment of 7 with 1N sodium methoxide followed by exposure to aqueous trifluoroacetic acid, and ether cleavage furnished 7-deazaguanosine. 2'-Deoxy-7-deazaguanosine and 2'-deoxy-7-deaza-6-thioguanosine were also prepared by using similar sequence of reactions employing 4 and 1-chloro-2-deoxy-3,5-di-O-p-toluoyl-α-D-erythro-pentofuranose.