Efficient and .BETA.-Stereoselective Synthesis of 4(5)-Methyl-5(4)-(5-amino-5-deoxy-.BETA.-D-ribofuranosyl)imidazole and Related Compounds Exhibiting Antiulcer Activity.
debenzylation gave 21, which was successively derived to the 5'-amino derivative 1 via the 5'-substituted phthalimide 23, followed by hydrazine degradation in excellent yield. Compound 1 was then converted into the 5'-cyanoguanidine 2 in 79% yield. The 5'-amino derivatives 3-9 lacking a methyl group were efficiently synthesized. Among them, the cyanoguanidine 5 and phenylthiourea 8 exhibited antiulcer activities