110522-47-9

Amino-bisphosphonates (alendronate, pamidronate) were covalently linked in a three step synthesis, with protected and triazolylated derivatives of therapeutically used nucleoside analogs (5-FdU, araC, AZT) by substitution of their triazolyl residue. From the deprotected and chromatographically purified reaction mixtures N4-[alkyl-(hydroxyphosphono) phosphonate]-cytidine combining two differently cytotoxic functions were obtained. This new family of bisphosphonates (BPs) contains as novelty an alkyl side chain with a cytotoxic nucleoside. The BPs moiety allows for a high binding to hydroxyapatite which is a prerequisite for bone targeting of the drugs. In vitro binding of 5-FdU-alendronate (5-FdU-ale) to hydroxyapatite showed a sixfold increased binding of these BPs as compared to 5-FdU. Exploratory cytotoxic properties of 5-FdU-ale were tested on a panel of human tumor cell lines resulting in growth inhibition ranging between 5% and 38%. The determination of IC 50-concentrations of the conjugate in Lewis lung carcinoma and murine macrophages showed an incubation time dependent growth inhibition with higher sensitivity towards the tumor cells. We assume that the antimetabolite-BPs can be cleaved into different active metabolites that may exert cytotoxic and other therapeutic effects. However, the underlying mechanisms of these promising new antimetabolite-BPs conjugates remain to be evaluated in future experiments.

The preparation of some novel fluorodeoxy nucleosides in good yields by the fluorination of unsaturated intact nucleosides with elemental fluorine at -78 deg C in mixtures of chloroform, ethanol and fluorotrichloromethane is described.This is the first example of the fluorination of an intact nucleoside by elemental fluorine and represents a considerable step forward in the use of the element in the synthesis of bioactive species.Thus, we were able to obtain 1-(2',3'-didehydro-2',3'-dideoxy-β-D-ribofuranosyl)-5-fluorouracil (6), 1-(2',3'-didehydro-2',3'-dideoxy-2',3'-difluoro-β-D-ribofuranosyl)-5-fluorouracil (7), 1-(2',3'-didehydro-2',3'-dideoxy-2-fluoro-β-D-ribofuranosyl)-5-fluorouracil (8), 1-(2',3'-dideoxy-2',3'-difluoro-β-D-ribofuranosyl)-5-fluorocytosine (10), 2',3'-dideoxy-5-fluorouridine (11), 1-(2',3'-dideoxy-2'-fluoro-β-D-arabinofuranosyl)-5-fluorouracil (12), 1-(2',3',5'-tri-O-acetyl-β-D-ribofuranosyl)-5-fluorouracil (13), 1-(2-deoxy-3,5-di-O-acetyl-β-D-ribofuranosyl)-5-fluorouracil (14) and (5R,6S)- and (5S,6R)-1-(3',5'-anhydro-2-deoxy-β-D-threo-pentofuranosyl)-difluoro-5,6-dihydro-5-methyluracil (16 and 17) by a series of fluorinations and deprotections.From the products we have obtained, it is clear that (at least in these fluorinations) the addition of the fluorine is in a cis mode.

The invention discloses a preparation method of high-purity 5-fluro-deoxyuridine. The preparation method comprises the following steps: (A) mixing a 5-fluro-deoxyuridine derivative as shown in a structural formula B and a reagent capable of removing hydroxyl protecting groups, and reacting at the temperature of 5-40 DEG C, thereby obtaining a reaction system A; (B) dissolving the reaction system A in an organic solvent, and crystallizing at the temperature of 0-15 DEG C, thereby obtaining the 5-fluro-deoxyuridine as shown in a structural formula A. The reagent for removing the hydroxyl protecting groups is selected from ammonia water and methanol amine, an aqueous solution of sodium hydroxide and potassium hydroxide, glacial acetic acid, trifluoroacetic acid or tetrabutylammonium fluoride.

Unambiguous characterization of 5-substituted-4-thiopyrimidine nucleosides (ribonucleosides and 2'-deoxynucleosides) was performed using NMR spectroscopy. Assignments of all proton and carbon signals of 5-bromo-4-thiouridine and related nucleosides were systematically carried out and firmly established by COSY and HMQC techniques. The NMR data of various 4-thiopyrimidine nucleosides are compared, and the key contributing factors discussed. The approach presented here is applicable to other modified nucleosides and nucleotides, as well as nucleobases. Copyright

The substrate recognition of Pseudomonas cepacia lipase in the acylation of nucleosides was investigated by means of rational substrate engineering for the first time. P. cepacia lipase displayed excellent 3′-regioselectivities (96 to >99%) in the lauroyl

The substrate recognition of Candida antarctica lipase B (CAL-B) in the acylation of nucleosides was revealed through rational substrate engineering for the first time. CAL-B displayed lower activities and excellent 5′-regioselectivities (94 to >99%) in t

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A lipase from Pseudomonas sp. (Amano PS) catalyzes regioselecfive acylation of the 3′-hydroxyl groups of FUdR and CF3UdR.

The title reaction provides a generally useful tool for nucleoside synthesis.The stereoselectivities are highly influenced by the fluoride substrates, and steric course of the reaction of O-benzylated ribofuranosyl fluoride is solvent dependent.