Synthesis of enantiomerically pure (purin-6-yl)phenylalanines and their nucleosides, a novel type of purine-amino acid conjugates.
[Chemical reaction: See text] Enantiomerically or diastereomerically pure 4-(purin-6-yl)phenylalanines, a novel type of stable amino acid-purine conjugates, were synthesized by palladium-catalyzed cross-coupling reactions of protected 4-boronophenylalanines or 4-(trimethylstanyl)phenylalanines with diverse 6-halopurines (9-benzyl-6-halopurines and 9-(tetrahydropyran-2-yl)-6-halopurines as well as acyl- and silyl-protected 6-halopurine ribonucleosides and 2-deoxyribonucleosides). Free purine bases and nucleosides bearing (S)- or (R)-phenylalanine in position 6 were obtained after complete deprotection of the products of cross-coupling reactions. Reactivity trends for both of these cross-coupling and deprotection protocols have been compared in terms of practicability, efficiency, and stereoselectivity.
Capek
Petr
P
Centre for New Antivirals and Antineoplastics, Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, CZ-16610, Prague 6, Czech Republic.
Pohl
Radek
R
Hocek
Michal
M
D000596:Amino Acids / Q000737:chemistry*; D000998:Antiviral Agents / Q000138:chemical synthesis; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009705:Nucleosides / Q000138:chemical synthesis*; D010649:Phenylalanine / Q000737:chemistry*; D011687:Purines / Q000138:chemical synthesis*; D013237:Stereoisomerism
D000596:Amino Acids; D000998:Antiviral Agents; D007202:Indicators and Reagents; D009705:Nucleosides; D011687:Purines; D010649:Phenylalanine