Nucleosides. CVI. Syntheses of 1-N-methyl-5-(beta-D-ribofuranosyl)uracil (1-N-methyl-phi-uridine) and its identity with a metabolite elaborated by Streptomyces platensis var. clarensis.

Very recently, 1-N-methyl-psi-uridine was isolated from the culture filtrate of Streptomyces platensis var. clarensis along with an antibacterial and antiviral antibiotic, U-44590. We achieved chemical syntheses of 1-N-methyl-psi-uridine by selective methylation of psi-uridine in two different routes and established the identity of the synthetic nucleoside with the natural product.