Uridine 5 -deoxy-, preparation

Perfluoroalkyl)-5 -deoxy-5 -fluoro- and 5-(perfluoroalkyl)-2, 5 -di-deoxy-5 -fluoro-uridines were prepared " from 840 and 834, respectively, using perfluoroalkyl-copper complexes. Among them, 5 -deoxy-5 -fluoro-(846) and 2, 5 -dideoxy-5 -fluoro-5-(perfluoroethyl)uridine (839) were particularly effective against Ehrlich ascites carcinoma. 5-Hydroxyl (847) and 5-amino or 5-alkylamino (5-NHMe, -NHBu, -NHCH2Ph, -morpholino, -piperidino, and -pyrrolo) analogs (848) of 840 were prepared. The a anomer of 5 -deoxy-5 -fluorouridine (840) was also synthesized. "... 

A 2, 3 -unsaturated derivative of uridine was prepared by base-catalyzed elimination of the methylsulfonyloxy group of l-[2-deoxy-3-0- (methylsulfonyl) - 5 - O - trityl -/3-D-threo-pentofuranosyljuracil.362 The cis relationship between the aglycon and the sulfonyloxy group precluded occurrence of intramolecular displacement. 

In fluorine-18 chemistry some enzymatic transformations of compounds already labelled with fluorine-18 have been reported the synthesis of 6-[ F] fluoro-L-DOPA from 4-[ F]catechol by jS-tyrosinase [241], the separation of racemic mixtures of p F]fluoroaromatic amino acids by L-amino acylase [242] and the preparation of the coenzyme uridine diphospho-2-deoxy-2-p F]fluoro-a-o-glucose from [ F]FDG-1-phosphate by UDP-glucose pyrophosphorylase [243]. In living nature compounds exhibiting a carbon-fluorine bond are very rare. 

Fermentation procedures for preparing uridine 5 -(2-acetamido-2-deoxy-a-D-glucopyranosyl pyrophosphate) have also been reported. One of them255 involves the cultivation of Helminthosporium sativum in the presence of 2-amino-2-deoxy-D-glucose and the antibiotic polyoxin the latter is an inhibitor of chitin biosynthesis. The other256 utilized the incubation of yeast cells with uridine 5 -phosphate in the presence of an excess of 2-amino-2-deoxy-D-glucose and inorganic phosphate.257... 

The intravenous injection of 2-amino-2-deoxy-D-glucose-14C into rats, and subsequent isolation of the uridine diphosphate N-acetyl-hexosamine fraction, has been suggested as a fast and convenient method for preparing small amounts of a mixture of radioactive uridine 5 -(2-acetamido-2-deoxy-a-D-gIucopyranosyl pyrophosphate) and uridine 5 -(2-acetamido-2-deoxy-a-D-galactopyranosyl pyrophosphate). 

The analogous conversion of the uridine derivative 107d has been observed in extracts of tobacco leaves136 and Chlorella cells,137 although the enzyme has not yet been purified. The enzymic reactions described here are frequently used for preparation of the 6-deoxy-hexosyl-4-ulose esters of nucleoside pyrophosphates that are inacces-... 

Stoichiometric quantities of uridine diphosphate glucose were used, in the presence of a transfer enzyme, sucrose synthetase, in the soluble state (extraction given). Coupling with modified D-fructose gave sucroses modified on the D-fructosyl group, on the 1 -3-mmol scale. Thus were prepared l -deoxy-l -fluoro- (59%),98 4 -deoxy-4 -fluoro- (16%), and l -azido-l -deoxy-sucrose (15%).71 6-Deoxy-6-fluoro-D-glucose was isomerized to 6-deoxy-6-fluoro-D-fructose with isomerase, and gave 6 -deoxy-6 -fluoro-sucrose.71... 

Condensation of LXVIa (R = p-toluyl) with monomercurithymine (prepared from 1-acetylthymine) produces a mixture of acylated nucleoside anomers (LXVlb and LXVIc, R = thyminyl) which are separated and de-esterified to thymidine and a-thymidine. Similarly, reaction of N-acetylcytosinemercury (LV) with LXVIa (R = p-chlorobenzoyl) yields the a and ft anomers of acylated 2-deoxycytidine which, after separation and deacylation, are converted smoothly to 2-deoxycytidine (LXVlb, R = H, R = cytosinyl) and its a anomer (LXVIc). In like manner, 2-deoxy-5 -fluoro-uridine and -cytidine were synthesized, along with their... 

For the preparation of )3-D-glucopyranosyl (1 —> 4)-2-acetamido-2-deoxy- -D-glucopyranosyl-(l —> 0)-elymoclavine (11), the extension of previously prepared 2-acetamido-2-deoxy-)3-D-glucopyranosyl-(l —> 0)-elymoclavine (10) by the use of bovine -1,4-galactosyltranferase was chosen. Uridine 5 -di-phosphogalactose (UDP-Gal) served as a substrate, and alkaline phosphatase from calf intestine (EC 3.1.3.1) was used to remove feedback inhibition caused by the UDP produced [28]. 

Reductive desulfurization of the thiocarbonyl group with Raney nickel results in good yields of ethers. 3 -0-Benzyl-2 -deoxy-5-trifluoromethyl-P-uridine (43), claimed as a possible antitumor agent, has been prepared in this way (equation 39). ... 

---