No abstract

-The key precursor, N 2 -(N,N-dimethylaminomethylene)-6-hydroxymethyl-8-methyl-3-[2-(4-nitrophenyl)ethyl]-7-xanthopterin (9) was efficiently prepared from 2,5-diamino-6-methylamino-3H-pyrimidin-4-one (3) and ethyl 3-(tert-butyldimethylsilyloxy)-2-oxopropionate (11). The first synthesis of asperopterin-A (2b) was achieved by treatment of 9 with 1-O-acetyl-2,3,5-tri-O-benzoyl-β-D-ribofuranose (15) in the presence of tin(IV) chloride, followed by removal of the protecting groups.

No abstract

Synthesis of 6-Hydroxymethylpterin αand β-D-Glucosides. -The selective αand β-glycosylation of a pterin derivative is achieved by treatment of key precursor (I) with α-D-glycosyl donors (II) and (V). Removal of the protecting groups of β-D-glucoside (III) is performed by successive cleaving of the benzoyl groups, the dimethylaminomethylene group, and the Npe group. A four-step procedure is employed to remove the protecting groups of α-D-glucoside (VI). -(HANAYA*, T.; BABA, H.; EJIRI, K.; YAMAMOTO, H.; Heterocycles 80 (2010) 2, 1013-1025,

Asperopterin‐A (VIII) is prepared via condensation of pyrimidine (I) with oxopropionate (II) and a SnCl4‐promoted glycosylation of xanthopterin (V) as key steps.