Nucleic Acid Related Compounds. 51. Synthesis and Biological Properties of Sugar-Modified Analogues of the Nucleoside Antibiotics Tubercidin, Toyocamycin, Sangivamycin, and Formycin

Article abstract of DOI:10.1021/jm00386a007

Treatment of 7-amino-3-β-D-ribofuranosylpyrazolo<4,3-d>pyrimidine (formycin) with α-acetoxyisobutyryl bromide followed by deprotection of the resulting trans-vicinal acetoxy bromides and hydrogenolysis of the separated bromohydrins gave 2'-deoxy- (23 percent) and 3'-deoxyformycin (32 percent) after complete deprotection and purification of their hydrochloride salts.An analogous sequence gave 3'-deoxytoyocamycin and/or 3'-deoxysangivamycin in ca. 80 percent yields from toyocamycin.Antiviral, antineoplastic, and antimetabolic effects were evaluated for the formycin compounds and 4-amino-7-β-D-ribofuranosylpyrrolo<2,3-d>pyrimidine (tubercidin), its 5-cyano- (toyocamycin), and 5-carbamoyl- (sangivamycin) antibiotic congeners in comparison with their 2'-deoxy, 3'-deoxy, and arabino analogues.In all cases, the modified-sugar compounds were less cytotoxic than the parent antibiotics.The majority also exhibited lower antiviral potency.However, the xylo-tubercidin analogue retained potent antiherpes 1 and 2 activity with decreased cytotoxity.Labeled metabolite studies suggested that effects of these compounds on RNA and/or protein synthesis might be more significant than interference with DNA synthesis.