Abstract
The O-cyclonucleosides of hypoxanthine, 6-mercaptopurine, 6-methylmercaptopurine, and purine were synthesized. Cyclonucleosides of hypoxanthine, and 6-mercaptopurine were synthesized i) by the derivatization of corresponding adenine cyclonucleosides and ii) by the cyclization of appropriate 2'-or 3'-TPS-derivatives. Cyclonucleosides of 6-methylmercaptopurine and purine were synthesized from the corresponding 6-mercaptopurine cyclonucleosides by methylation and Raney Nickel desulfurization. Ultraviolet spectrum (UV), nuclear magnetic resonance (NMR), circular dichroism (CD) and Mass spectra of these cyclonucleosides were measured. It was found in the CD spectrum that the purine 8, 2'-cyclonucleoside had a larger magnitude of Cotton effect than its 8, 3'-counterpart, in contrast to the order found in other cyclonucleosides.