Patent ID: 6969766

Claim:
A compound having formula I: wherein E is nitrogen or Câ€”Râ€²; J is sulfur or oxygen; Râ€², R1, R2, R3, R4 is independently H, halogen, alkyl, nitro, cyano, alkoxy, halogenated alkyl, halogenated alkoxy, phenyl or halogenated phenyl; R5 is H or protected or unprotected side chain of natural or unnatural Î±-amino acid; and B is adenine, which is protected by protecting group having a formula; wherein R7 has a formula; wherein Y 1 , Y 2 , Y 3 , Y 4 , Y 5 , Y 6 , Y 7 , Y 8 , Y 9 , Y 10 is independently selected from hydrogen, halogen, alkyl, and alkoxy; or wherein Z 1 , Z 2 , Z 3 , Z 4 , Z 5 is independently selected from hydrogen, halogen, alkyl, alkoxy, and methylene dioxy of adjacent two residues; or wherein R8 is alkyl or phenyl.