Patent ID: 6974856

Claim:
A block copolymer represented by the general formula (I) wherein AI represents a hydroxyl group or a group of the formula wherein (i) p is an integer of 1 to 10, and R 1 and R 2 each independently represent a C 1-10 alkoxy, aryloxy or aryl-C 1-3 alkyloxy group, or R 1 and R 2 are united together to represent an optionally C 1-6 alkyl-substituted ethylenedioxy group [—O—CH(R′)—CH—O— in which R′ is a hydrogen atom or a C 1-6 alkyl group] or an oxy (═O) radical; or (ii) p is 0 or 1, and R 1 and R 2 are united together to represent an atomic group constituting a residue derived from a monosaccharide or its derivative; or (iii) p is 0 or 1, and R 1 and R 2 each independently represent a hydrogen atom, a C 1-20 alkyl group, a phenyl group, or a C 1-20 alkyl or phenyl group having one or two substituents selected from amino optionally protected by one or two amino-protecting groups, carboxyl optionally protected by a carboxyl-protecting group, and mercapto optionally protected by a mercapto-protecting group; and (iv) R 3 and R 4 each independently represent a hydrogen atom or an organosilyl amino-protecting group, or R 3 and R 4 represent organosilyl amino-protecting groups that, together with the nitrogen atom to which they are attached, can form a four- to seven-membered disila-azacyclo heterocyclic ring, R represents a hydrogen atom, NP represents a residue derived from a nucleophilic reagent, m is an integer of 2 to 20,000, and n is an integer of 1 to 20,000.