Jose Soria

Ultrasonically accelerated cycloaddition - rearrangement of enol ethers

Abstract Cycloaddition-rearrangement reactions of methyl cyclohexenyl ethers with p-bromobenzenesulfonyl azide in neat homogeneous admixture are substanially accelerated by low-wattage ultrasound. Using ultrasound approximately the same yields of reaaranged products are obtained in less time at lower temperature than observed at ambient sonic frequencies and elevated temperature. A previously unreported product structural type has also been found.

A GENERAL SYNTHETIC METHOD OF 5-CARBORANYLURACIL NUCLEOSIDES WITH POTENTIAL ANTIVIRAL ACTIVITY AND USE IN NEUTRON CAPTURE THERAPY

Abstract Previous biochemical and pharmacological studies indicated that 5-o-carboranyl-2′-deoxyuridine is a lead candidate for boron neutron capture therapy. This prompted the development of a rapid and stereoselective N 1-glycosylation reaction of silylated 5-o-carboranyluracil with a variety of protected sugars. The key intermediate, 5-o-carboranyluracil (6), was prepared from 5-iodouracil in six steps. A novel coupling procedure of the 2,4-dimethoxy-5-ethynylpyrimidine (4) with decaborane without activator was used. Silylated 6 was coupled with a variety of carbohydrates under mild conditions to produce several carborane containing nucleosides. In each case, the stereochemistry and stereoselectivity of the glycosylation reaction was not affected by the presence of the carborane at the 5-position of the uracil and produced exclusively closo [closo-1,2-C2B10H12 cage] nucleosides. This was confirmed by X-ray structure determination of racemic 5-carboranyl-2′,3′-dideoxy-3′-thiauridine. This compound demon...

Synthesis, Antiviral Activity, Cytotoxicity, and Cellular Pharmacology of 5-Carboranyl-Pyrimidine Nucleosides

Our laboratories have been involved in the synthesis and evaluation of nucleosides for the treatment of viral infections and cancer for more than a decade. Our group was the first to synthesize 5-dihydroxyboryl-2’-deoxyuridine (DBDU), a novel compound that was shown by us to destroy hamster V-79 cells when irradiated with low energy neutrons, thus producing cell destruction by a boron neutron capture reaction.1 This reaction is a consequence of the 10B(n,α)7Li reaction itself, as well as a concomitant self-sensitization to those radiations provided by the presence of the nucleoside analogue in DNA. DBDU is related to the natural nucleoside thymidine and may be useful for the treatment of gliomas and other human tumors. The aim of this work was to synthesize additional boron containing nucleosides that are hydrolytically stable and that are substrates for nucleoside kinases found in tumor cells. The design of the ideal compound for BNCT requires the following criteria:

Cycloaddition-rearrangement of cyclohexadienol ethers. A versatile and selective synthesis of cyclopentenoid systems

Abstract 1,4-Cyclohexadienol ethers prepared by the Birch reduction of alkyl aryl ethers react at ambient pressure and moderate temperatures with p-bromobenzenesulfonyl azide to yield cyclopentenecarboximidates. The cycloaddition-rearrangement is highly specific for the more electron rich of the two double bonds of the diene.