Patent ID: 7846962

Claim:
A compound of formula III: wherein X is selected from the group consisting of oxygen, NH and CH 2 ; and R is selected from the group consisting of 3′-CH 2 CH(CO 2 Me)NH 2 , 3′-CH 2 CH(CO 2 Me)NHFmoc, 3′-t-Bu, 3′-OH, 3′-O(CH 2 ) 3 CHCH 2 , 3′-O(CH 2 ) 4 Br, 3′-O(CH 2 ) 4 NMe 2 , 3′-O(CH 2 ) 4 N 3 , 3′- 3′-O(CH 2 ) 4 NH 2 , 3′-CF 3 , 3′-CH 3 , 3′-n-heptyl, 3′-n-nonyl, 3′-i-Bu, 3′-i-propyl, 3′-n-propyl, 3′-n-octyl, 3′-Et, 3′-n-pentyl, 3′-n-Bu, 3′-n-hexyl, 3′-n-cyclopentyl, 3′-n-cyclohexyl, 4-NHSO 2 (4-tBu)Ph and 3′-NHSO 2 (4-tBu)Ph.