Synthesis and antiviral evaluation of thieno[3,4-d]pyrimidine C-nucleoside analogues of 2',3'-dideoxy- and 2',3'-dideoxy-2',3'-didehydro-adenosine and -inosine.

Several thieno[3,4-d]pyrimidine derivatives, including four hitherto unknown 2',3'-dideoxy- and 2',3'-dideoxy-2',3'-didehydro-C-nucleoside analogues of adenosine and inosine have been synthesized. When evaluated in cell culture experiments against human immunodeficiency virus, none of the tested compounds exhibited any significant antiviral effect, while two of them showed some cytotoxicity.

1,3-Dipolar cycloaddition of hydrazones with α-oxo-ketenes: a three-component stereoselective entry to pyrazolidinones and an original class of spirooxindoles.

Stereodefined monocyclic, spirobicyclic, and bis-spirotricyclic pyrazolidin-3-ones can be prepared efficiently by a three-component reaction involving a 1,3-dipolar cycloaddition of azomethine imines obtained from hydrazones with α-oxo-ketene dipolarophiles generated in situ. The reaction allows the creation of four covalent bonds and two contiguous chiral quaternary centers with excellent diastereoselectivity in a single catalyst/additive-free, highly atom-economical transformation. From a fundamental point of view, the reaction introduces α-oxo-ketenes as effective dipolarophiles in 1,3-dipolar cycloadditions.

Synthesis and study of 9-deazaguanosine derivatives as potential inhibitors of RNA virus replication.

9-Deazaguanosine and the alpha and beta anomers of its 2'-C-methyl counter part, have been synthesized and evaluated against a broad range of RNA viruses, including hepatitis C virus.