Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
52 words
A polyethylene glycol derivative of the formula wherein R₁ and R₂ are the same or different and each represents a lower alkyl and m and n are same or different and each represents an optional positive integer which renders the average molecular weight of the polyethylene glycol moiety about 1,000 to 12,000.
Claim 2
Dependent Claim
52 words
A polyethylene glycol derivative of the formula wherein R₁ and R₂ are the same or different and each represents a lower alkyl and m and n are same or different and each represents an optional positive integer which renders the average molecular weight of the polyethylene glycol moiety about 1,000 to 12,000.
Claim 3
Dependent Claim
33 words
A polyethylene glycol derivative as claimed in Claim 1 which is selected from a group consisting of 3,5-bis-methoxypolyethylene glycol phenylglyoxal and 3-monomethoxypolyethylene glycol (average molecular weight 2,000)-5-monomethoxypolyethylene glycol (average molecular weight 4,500) phenylglyoxal.
Claim 4
Dependent Claim
23 words
A modified peptide in which the guanidino group in the peptide is modified by a polyethylene glycol derivative as claimed in Claim 1.
Claim 5
Dependent Claim
63 words
A modified peptide as claimed in Claim 3 selected from among a group consisting of superoxide dismutase modified by 3,5-bis-methoxypolyethylene glycol phenylglyoxal, insulin-like growth factor-I modified by 3,5-bis-methoxy polyethylene glycol phenylglyoxal, insulin-like growth factor-II modified by 3,5-bis-methoxypolyethylene glycol phenylglyoxal, calcitonin gene related peptide modified by 3,5-bis-methoxypolyethylene glycol phenylglyoxal, elastase modified by 3,5-bis-methoxypolyethylene glycol phenylglyoxal and superoxide dismutase modified by 3-monomethoxypolyethylene glycol-5-monomethoxypolyethylene glycol phenylglyoxal.
Claim 6
Dependent Claim
25 words
A method for producing a modified peptide which comprises reacting a polyethylene glycol derivative as claimed in Claim 1 with a peptide having guanidino group.
Claim 7
Dependent Claim
42 words
A method for producing a modified peptide which comprises protecting the amino group(s) of a peptide having guanidino group and then reacting the amino-protected peptide with a polyethylene glycol derivative as claimed in Claim 1, followed by deprotection of the amino-protective group(s).