Treatment of L-biopterin (1) with N, N-dimethyformamide dimethyl- (or diethyl)acetal and then with acetic anhydride in pyridine gave 1,2-di-0-acetyl-N:2-(N, N-dimethylaminomethylene)-L-biopterin (4), which was converted by the Mitsunobu reaction into 3-methyl (5) and 3-p-nitrophenetyl derivatives (7). The protective groups on the side chain diols and N of these compounds were selectively cleaved to furnish products 6, 8-10 among which 9 is naturally occurring 3-methyl-L-biopterin and 8 is N2:,N(3)-protected biopterin, a versatile intermediate for various reactions on the side-chain diol. In contrast, the same Mitsunobu reactions of tri-N2::1,2'-0-acetyl-L-biopterin (11) afforded 04-methyl (12) and 04-NPE derivatives (13), both of which yielded 04-methyl-L-biopterin (14) and subsequently led to 4-amino-L-biopterin (18).
- Biopterin 3-Methyl-L-biopterin 04-Methyl-L-biopterin Selective alkylation Selective protection N2
- N(3)-Protected-L-biopterin N
- N-Dimethylaminomethylene p-Nitrophenethyl Selective deprotection Synthesis Pteridines
ASJC Scopus subject areas
- Molecular Medicine
- Clinical Biochemistry