U.S. patent application number 15/300699 was filed with the patent office on 2017-04-20 for hydrophilic polymer derivative having cyclic benzylidene acetal linker.
This patent application is currently assigned to NOF CORPORATION. The applicant listed for this patent is NOF CORPORATION. Invention is credited to Takuma TSUBUSAKI, Yuji YAMAMOTO.
Application Number | 20170107325 15/300699 |
Document ID | / |
Family ID | 54240504 |
Filed Date | 2017-04-20 |
United States Patent
Application |
20170107325 |
Kind Code |
A1 |
TSUBUSAKI; Takuma ; et
al. |
April 20, 2017 |
HYDROPHILIC POLYMER DERIVATIVE HAVING CYCLIC BENZYLIDENE ACETAL
LINKER
Abstract
A hydrophilic polymer derivative having a cyclic benzylidene
acetal linker represented by the following formula (1):
##STR00001## wherein R.sup.1 and R.sup.6 are each independently a
hydrogen atom or a hydrocarbon group; R.sup.2, R.sup.3, R.sup.4 and
R.sup.5 are each independently an electron-withdrawing or
electron-donating substituent or a hydrogen atom; X.sup.1 is a
chemically reactive functional group; P is a hydrophilic polymer, s
is 1 or 2, t is 0 or 1, and s+t is 1 or 2; w is an integer of 1 to
8; and Z.sup.1 and Z.sup.2 are each independently a selected
divalent spacer.
Inventors: |
TSUBUSAKI; Takuma;
(Kawasaki-shi, Kanagawa, JP) ; YAMAMOTO; Yuji;
(Kawasaki-shi, Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NOF CORPORATION |
Tokyo |
|
JP |
|
|
Assignee: |
NOF CORPORATION
Tokyo
JP
|
Family ID: |
54240504 |
Appl. No.: |
15/300699 |
Filed: |
March 30, 2015 |
PCT Filed: |
March 30, 2015 |
PCT NO: |
PCT/JP2015/060013 |
371 Date: |
September 29, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C07D 317/20 20130101;
C08G 65/329 20130101; C08G 65/33324 20130101; C08G 65/33337
20130101; C07D 317/22 20130101; C07D 317/28 20130101; C08G 65/3346
20130101; C08G 65/337 20130101; C07D 405/06 20130101; C07D 317/24
20130101; C08G 65/333 20130101; C08G 65/33341 20130101; C08G
65/3317 20130101; C08G 65/33396 20130101 |
International
Class: |
C08G 65/333 20060101
C08G065/333; C07D 317/24 20060101 C07D317/24; C07D 405/06 20060101
C07D405/06; C07D 317/20 20060101 C07D317/20 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 31, 2014 |
JP |
2014-072356 |
Sep 22, 2014 |
JP |
2014-193039 |
Claims
1. A hydrophilic polymer derivative having a cyclic benzylidene
acetal linker represented by formula (1): ##STR00085## wherein
R.sup.1 and R.sup.6 are each independently a hydrogen atom or a
hydrocarbon group; R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are each
independently an electron-withdrawing or electron-donating
substituent or a hydrogen atom; X.sup.1 is a chemically reactive
functional group; P is a hydrophilic polymer, s is 1 or 2, t is 0
or 1, and s+t is 1 or 2; m is an integer of 1 to 8; and Z.sup.1 and
Z.sup.2 are each independently a selected divalent spacer.
2. The hydrophilic polymer derivative as claimed in claim 1,
wherein s is 1 and t is 0, R.sup.2 and R.sup.5 are each a hydrogen
atom, and a sum (.SIGMA..sigma.) of substituent constants (.sigma.)
in R.sup.3, R.sup.4 and P--Z.sup.1 satisfies
-0.30.ltoreq..SIGMA..sigma..ltoreq.1.05.
3. The hydrophilic polymer derivative as claimed in claim 1,
wherein s is 1 and t is 0, at least one of R.sup.2 and R.sup.5 is
the substituent, and a sum (.SIGMA..sigma.) of substituent
constants (.sigma.) in R.sup.3, R.sup.4 and P--Z.sup.1 satisfies
-1.71.ltoreq..SIGMA..sigma..ltoreq.0.88.
4. The hydrophilic polymer derivative as claimed in claim 1,
wherein s is 1 and t is 1, or s is 2 and t is 0, R.sup.2 and
R.sup.5 are each a hydrogen atom, and a sum (.SIGMA..sigma.) of
substituent constants (.sigma.) in R.sup.3, R.sup.4 and P--Z.sup.1
satisfies -0.19.ltoreq..SIGMA..sigma..ltoreq.0.57.
5. The hydrophilic polymer derivative as claimed in claim 1,
wherein s is 1 and t is 1, or s is 2 and t is 0, at least one of
R.sup.2 and R.sup.5 is the substituent, and a sum (.SIGMA..sigma.)
of substituent constants (.sigma.) in R.sup.3, R.sup.4 and
P--Z.sup.1 satisfies -0.98.ltoreq..SIGMA..sigma..ltoreq.0.48.
6. The hydrophilic polymer derivative as claimed in claim 1,
wherein X.sup.1 is selected from the group consisting of an active
ester group, an active carbonate group, an aldehyde group, an
isocyanate group, an isothiocyanate group, an epoxy group, a
maleimide group, a vinyl sulfone group, an acryl group, a
sulfonyloxy group, a carboxy group, a thiol group, a dithiopyridyl
group, an .alpha.-haloacetyl group, an alkynyl group, an allyl
group, a vinyl group, an amino group, an oxyamino group, a
hydrazide group and an azide group.
7. The hydrophilic polymer derivative as claimed in claim 1,
wherein X.sup.1 is selected from the group consisting of formula
(a), formula (b), formula (c), formula (d), formula (e), formula
(f), formula (g), formula (h), formula (i), formula (j), formula
(k), formula (l), formula (m) and formula (n): ##STR00086## wherein
R.sup.7 is a hydrogen atom or a sulfo group; R.sup.8 and R.sup.11
are each independently a hydrogen atom or a hydrocarbon group
having from 1 to 5 carbon atoms; R.sup.9 is a hydrocarbon group
having from 1 to 10 carbon atoms which may contain a halogen atom;
and R.sup.10 is a halogen atom selected from a chlorine atom, a
bromine atom and an iodine atom.
8. The hydrophilic polymer derivative as claimed in claim 1,
wherein Z.sup.1 and Z.sup.2 are each independently an ether bond,
an ester bond, a carbonate bond, a urethane bond, an amide bond, a
secondary amino group, an alkylene group containing any of these
bonds and group, a single bond or an alkylene group, and in a case
where at least one of Z.sup.1 and Z.sup.2 is an ether bond, an
ester bond, a carbonate bond, a urethane bond, an amide bond, a
secondary amino group or an alkylene group containing any of these
bonds and group and a plurality of identical structural units are
connected, a number of the structural units is 2 or less.
9. The hydrophilic polymer derivative as claimed in claim 1,
wherein P is a linear polyethylene glycol having a hydrocarbon
group or a chemically reactive functional group at its
terminal.
10. The hydrophilic polymer derivative as claimed in claim 9,
wherein w is 1, and P is represented by formula (2):
Y--(OCH.sub.2CH.sub.2).sub.n-- (2) wherein Y is a hydrocarbon group
having from 1 to 24 carbon atoms; and n is an integer of 3 to
2,000.
11. The hydrophilic polymer derivative as claimed in claim 9,
wherein w is 1, and P is represented by formula (3):
X.sup.2--Z.sup.3--(OCH.sub.2CH.sub.2).sub.n-- (3) wherein X.sup.2
is a chemically reactive functional group different from X.sup.1;
Z.sup.3 is a divalent spacer, and n is an integer of 3 to
2,000.
12. The hydrophilic polymer derivative as claimed in claim 1,
wherein P is a branched polyethylene glycol having a hydrocarbon
group or a chemically reactive functional group different from
X.sup.1 at its terminal.
13. The hydrophilic polymer derivative as claimed in claim 12,
wherein w is 1, and P is represented by formula (4): ##STR00087##
wherein Y is a hydrocarbon group having from 1 to 24 carbon atoms;
n is an integer of 3 to 1,000; and v is 0 or 2.
14. The hydrophilic polymer derivative as claimed in claim 12,
wherein w is 1, and P is represented by formula (5): ##STR00088##
wherein X.sup.2 is a chemically reactive functional group different
from X.sup.1; Z.sup.3 is a divalent spacer, n is an integer of 3 to
1,000; and v is 0 or 2.
15. The hydrophilic polymer derivative as claimed in claim 12,
wherein w is v+2, and P is represented by formula (6): ##STR00089##
wherein X.sup.2 is a chemically reactive functional group different
from X.sup.1; Z.sup.3 is a divalent spacer, n is an integer of 3 to
1,000; and v is 0 or 2.
16. The hydrophilic polymer derivative as claimed in claim 11,
wherein X.sup.2 is selected from the group consisting of an active
ester group, an active carbonate group, an aldehyde group, an
isocyanate group, an isothiocyanate group, an epoxy group, a
maleimide group, a vinyl sulfone group, an acryl group, a
sulfonyloxy group, a carboxy group, a thiol group, a dithiopyridyl
group, an .alpha.-haloacetyl group, an alkynyl group, an allyl
group, a vinyl group, an amino group, an oxyamino group, a
hydrazide group and an azide group.
17. The hydrophilic polymer derivative as claimed in claim 11,
wherein X.sup.2 is selected from the group consisting of formula
(a), formula (b), formula (c), formula (d), formula (e), formula
(f), formula (g), formula (h), formula (i), formula (j), formula
(k), formula (l), formula (m) and formula (n): ##STR00090## wherein
R.sup.7 is a hydrogen atom or a sulfo group; R.sup.8 and R.sup.11
are each independently a hydrogen atom or a hydrocarbon group
having from 1 to 5 carbon atoms; R.sup.9 is a hydrocarbon group
having from 1 to 10 carbon atoms which may contain a halogen atom;
and R.sup.10 is a halogen atom selected from a chlorine atom, a
bromine atom and an iodine atom.
18. The hydrophilic polymer derivative as claimed in claim 11,
wherein Z.sup.3 is an ether bond, an ester bond, a carbonate bond,
a urethane bond, an amide bond, a secondary amino group, an
alkylene group containing any of these bonds and group, a single
bond or an alkylene group, and in a case where Z.sup.3 is an ether
bond, an ester bond, a carbonate bond, a urethane bond, an amide
bond, a secondary amino group or an alkylene group containing any
of these bonds and group and a plurality of identical structural
units are connected, a number of the structural units is 2 or
less.
19. The hydrophilic polymer derivative as claimed in claim 1,
wherein P is polyethylene glycol having a number of terminals of 2
to 8, all the terminals of the polyethylene glycol constituting P
are each connected to Z.sup.1, and w is equal to the number of
terminals of the polyethylene glycol.
20. The hydrophilic polymer derivative as claimed in claim 19,
wherein P is selected from the group consisting of formula (r),
formula (s), formula (t), formula (u) and formula (v): ##STR00091##
wherein n is an integer of 3 to 2,000, and w is 2 when P is
represented by formula (r), w is 3 when P is represented by formula
(s), w is 4 when P is represented by formula (t), w is 4 when P is
represented by formula (u), and w is 8 when P is represented by
formula (v).
21. A cyclic benzylidene acetal linker compound represented by
formula (55): ##STR00092## wherein R.sup.1 and R.sup.6 am each
independently a hydrogen atom or a hydrocarbon group; R.sup.2,
R.sup.3, R.sup.4 and R.sup.5 are each independently an
electron-withdrawing or electron-donating substituent or a hydrogen
atom; X.sup.3 and X.sup.4, which may be the same or different, are
each independently a chemically reactive functional group; s is 1
or 2, t is 0 or 1, and s+t is 1 or 2; and Z.sup.1 and Z.sup.2 are
each independently a selected divalent spacer.
22. The cyclic benzylidene acetal linker compound as claimed in
claim 21, wherein s is 1 and t is 0, R.sup.2 and R.sup.5 are each a
hydrogen atom, and a sum (.SIGMA..sigma.) of substituent constants
(.sigma.) in R.sup.3, R.sup.4 and X.sup.3--Z.sup.1 satisfies
-0.30.ltoreq..SIGMA..sigma..ltoreq.1.05.
23. The cyclic benzylidene acetal linker compound as claimed in
claim 21, wherein s is 1 and t is 0, at least one of R.sup.2 and
R.sup.5 is the substituent, and a sum (.SIGMA..sigma.) of
substituent constants (.sigma.) in R.sup.3, R.sup.4 and
X.sup.3--Z.sup.1 satisfies
-1.71.ltoreq..SIGMA..sigma..ltoreq.0.88.
24. The cyclic benzylidene acetal linker compound as claimed in
claim 21, wherein s is 1 and t is 1, or s is 2 and t is 0, R.sup.2
and R.sup.5 are each a hydrogen atom, and a sum (.SIGMA..sigma.) of
substituent constants (.sigma.) in R.sup.3, R.sup.4 and
X.sup.3--Z.sup.1 is -0.19.ltoreq..SIGMA..sigma..ltoreq.0.57.
25. The cyclic benzylidene acetal linker compound as claimed in
claim 21, wherein s is 1 and t is 1, or s is 2 and t is 0, at least
one of R.sup.2 and R.sup.5 is the substituent, and a sum
(.SIGMA..sigma.) of substituent constants (.sigma.) in R.sup.3,
R.sup.4 and X.sup.3--Z.sup.1 satisfies
-0.98.ltoreq..SIGMA..sigma..ltoreq.0.48.
26. The cyclic benzylidene acetal linker compound as claimed in
claim 21, wherein X.sup.3 and X.sup.4 are each selected from the
group consisting of an active ester group, an active carbonate
group, an aldehyde group, an isocyanate group, an isothiocyanate
group, an epoxy group, a maleimide group, a vinyl sulfone group, an
acryl group, a sulfonyloxy group, a carboxy group, a thiol group, a
dithiopyridyl group, an .alpha.-haloacetyl group, an alkynyl group,
an allyl group, a vinyl group, an amino group, an oxyamino group, a
hydrazide group, an azide group and hydroxy group.
27. The cyclic benzylidene acetal linker compound as claimed in
claim 21, wherein X.sup.3 and X.sup.4 are each selected from the
group consisting of formula (a), formula (b), formula (c), formula
(d), formula (e), formula (f), formula (g), formula (h), formula
(i), formula (j), formula (k), formula (l), formula (m), formula
(n) and formula (o). ##STR00093## wherein R.sup.7 is a hydrogen
atom or a sulfo group; R.sup.8 and R.sup.11 are each independently
a hydrogen atom or a hydrocarbon group having from 1 to 5 carbon
atoms; R.sup.9 is a hydrocarbon group having from 1 to 10 carbon
atoms which may contain a halogen atom; and R.sup.10 is a halogen
atom selected from a chlorine atom, a bromine atom and an iodine
atom.
28. The cyclic benzylidene acetal linker compound as claimed in
claim 21, wherein Z.sup.1 and Z.sup.2 are each independently an
ether bond, an ester bond, a carbonate bond, a urethane bond, an
amide bond, a secondary amino group, an alkylene group containing
any of these bonds and group, a single bond or an alkylene group,
and in a case where at least one of Z.sup.1 and Z.sup.2 is an ether
bond, an ester bond, a carbonate bond, a urethane bond, an amide
bond, a secondary amino group or an alkylene group containing any
of these bonds and group and a plurality of identical structural
units are connected, a number of the structural units is 2 or
less.
29. The cyclic benzylidene acetal linker compound as claimed in
claim 21, wherein the functional group constituting any one of
X.sup.3 and X.sup.4 contains a protective group.
30. The hydrophilic polymer derivative as claimed in claim 14,
wherein X.sup.2 is selected from the group consisting of an active
ester group, an active carbonate group, an aldehyde group, an
isocyanate group, an isothiocyanate group, an epoxy group, a
maleimide group, a vinyl sulfone group, an acryl group, a
sulfonyloxy group, a carboxy group, a thiol group, a dithiopyridyl
group, an .alpha.-haloacetyl group, an alkynyl group, an allyl
group, a vinyl group, an amino group, an oxyamino group, a
hydrazide group and an azide group.
31. The hydrophilic polymer derivative as claimed in claim 14,
wherein X.sup.2 is selected from the group consisting of formula
(a), formula (b), formula (c), formula (d), formula (e), formula
(f), formula (g), formula (h), formula (i), formula (j), formula
(k), formula (l), formula (m) and formula (n): ##STR00094## wherein
R.sup.7 is a hydrogen atom or a sulfo group; R.sup.8 and R.sup.11
are each independently a hydrogen atom or a hydrocarbon group
having from 1 to 5 carbon atoms; R.sup.9 is a hydrocarbon group
having from 1 to 10 carbon atoms which may contain a halogen atom;
and R.sup.10 is a halogen atom selected from a chlorine atom, a
bromine atom and an iodine atom.
32. The hydrophilic polymer derivative as claimed in claim 14,
wherein Z.sup.3 is an ether bond, an ester bond, a carbonate bond,
a urethane bond, an amide bond, a secondary amino group, an
alkylene group containing any of these bonds and group, a single
bond or an alkylene group, and in a case where Z.sup.3 is an ether
bond, an ester bond, a carbonate bond, a urethane bond, an amide
bond, a secondary amino group or an alkylene group containing any
of these bonds and group and a plurality of identical structural
units are connected, a number of the structural units is 2 or
less.
33. The hydrophilic polymer derivative as claimed in claim 15,
wherein X.sup.2 is selected from the group consisting of an active
ester group, an active carbonate group, an aldehyde group, an
isocyanate group, an isothiocyanate group, an epoxy group, a
maleimide group, a vinyl sulfone group, an acryl group, a
sulfonyloxy group, a carboxy group, a thiol group, a dithiopyridyl
group, an .alpha.-haloacetyl group, an alkynyl group, an allyl
group, a vinyl group, an amino group, an oxyamino group, a
hydrazide group and an azide group.
34. The hydrophilic polymer derivative as claimed in claim 15,
wherein X.sup.2 is selected from the group consisting of formula
(a), formula (b), formula (c), formula (d), formula (e), formula
(f), formula (g), formula (h), formula (i), formula (j), formula
(k), formula (l), formula (m) and formula (n): ##STR00095## wherein
R.sup.7 is a hydrogen atom or a sulfo group; R.sup.8 and R.sup.11
are each independently a hydrogen atom or a hydrocarbon group
having from 1 to 5 carbon atoms; R.sup.9 is a hydrocarbon group
having from 1 to 10 carbon atoms which may contain a halogen atom;
and R.sup.10 is a halogen atom selected from a chlorine atom, a
bromine atom and an iodine atom.
35. The hydrophilic polymer derivative as claimed in claim 15,
wherein Z.sup.3 is an ether bond, an ester bond, a carbonate bond,
a urethane bond, an amide bond, a secondary amino group, an
alkylene group containing any of these bonds and group, a single
bond or an alkylene group, and in a case where Z.sup.3 is an ether
bond, an ester bond, a carbonate bond, a urethane bond, an amide
bond, a secondary amino group or an alkylene group containing any
of these bonds and group and a plurality of identical structural
units are connected, a number of the structural units is 2 or less.
Description
TECHNICAL FIELD
[0001] The present invention relates to a hydrophilic polymer
derivative which has an acid-hydrolysable acetal linker and is used
for chemical modification of a biofunctional molecule, for example,
a physiologically active protein, a peptide, an antibody, a nucleic
acid or a low molecular weight drug, or a drug carrier, for
example, a liposome or a polymer micelle.
BACKGROUND ART
[0002] In drug delivery system, the chemical modification of
biofunctional molecule or drug carrier with a hydrophilic polymer
having low antigenicity is an effective technique for increasing
water solubility and bioavailability of the drug or the like and
for prolonging circulation time in blood. On the other hand, it is
known that the formation of a hydrated layer by the hydrophilic
polymer after the drug or the like connected to the hydrophilic
polymer is transported to the tissue or site as a target decreases
interaction with a cell membrane and inhibits in vivo/intracellular
kinetics, for example, uptake into the cell or endosome escape. As
to such a problem, an approach to overcome the problem by detaching
the hydrophilic polymer chain from the drug and the like at a
suitable timing has been performed. Most of the strategies utilize
an environmental change at each portion of the living body, for
example, reductive environment or the presence or absence of a
specific enzyme, as a trigger of the detachment of the hydrophilic
polymer chain, and one of them is a technique of utilizing a change
in pH.
[0003] It is known that the periphery of a tumor tissue in the
living body is an acidic environment in comparison with a normal
tissue, and the pH of endosomal interior after the drug or the like
is introduced into the cell through an endocytosis pathway also
gradually decreases. Therefore, for the purpose of selectively
detaching the hydrophilic polymer under the acidic environment, a
large number of synthesis examples of hydrophilic polymer
derivative having an acid-hydrolysable acetal linker introduced
into the structure thereof have been reported. However, there is no
example in which the hydrolyzability of the acetal linker can be
controlled and there are not a few examples in which a problem
exists in the method of introducing the acetal linker.
[0004] For example, in Patent Document 1, a branched polyethylene
glycol derivative in which two chains of polyethylene glycol which
is a hydrophilic polymer having low antigenicity are connected
through an acetal group derived from various aldehydes or ketones,
and a synthetic method thereof are disclosed, but evaluation data
of hydrolyzability is not described. Also, the synthetic method
described therein is a method for obtaining a polyethylene glycol
derivative having an acetal linker by reacting an excess amount of
polyethylene glycol with various aldehydes or ketones, so that a
large amount of the unreacted polyethylene glycol remains after the
reaction. In the case where activation of the polymer terminal is
performed using the mixture as a raw material, an impurity in which
the terminal of the unreacted polyethylene glycol has also been
activated is by-produced. When the activated polyethylene glycol
containing such an impurity is used for drug modification, a drug
modified with the polyethylene glycol containing no acetal linker
is formed as a result, so that a large influence is exerted on the
in vivo kinetics and physical properties of the drug. Therefore, it
is necessary to remove the polyethylene glycol impurity before the
reaction with the drug, but in the case of the production in an
industrial scale, there is a possibility that the separation and
removal of the polymer impurity causes a severe adverse effect from
a technical and cost standpoint.
[0005] As another method for obtaining an acetal compound, there is
a method of reacting an alcohol with a vinyl ether under acidic
conditions. For example, in Non-Patent Document 1, polyethylene
glycol derivatives having various functional groups connected
through ethylidene acetal linkers are synthesized by reacting vinyl
ethers having various functional groups with polyethylene glycol.
However, also in the document, evaluation data of hydrolyzability
is not shown.
[0006] In the synthetic method described in Non-Patent Document 1,
since the vinyl ether which is a low-molecular weight compound is
used in an excess amount to polyethylene glycol, a large amount of
unreacted polyethylene glycol does not remain. However, the acetal
group to be introduced by the synthetic method contains an
ethylidene acetal structure, the kind of the acetal group which can
be introduced is limited. In the case of introducing a benzylidene
acetal group, a ketal structure is inevitably formed, and since the
ketal structure is sensitive to an acid, a dimer impurity in which
two chains of polyethylene glycol are connected through a ketal
group is by-produced in a large amount by a ketal exchange reaction
in the synthetic method. Therefore, the synthetic method described
in Non-Patent Document 1 is difficult to apply to the synthesis of
a polyethylene glycol derivative having a benzylidene acetal
linker.
[0007] On the other hand, in Non-Patent Document 2, several kinds
of polyethylene glycol derivatives in which a low-molecular weight
model drug is connected through an aliphatic or benzylidene acetal
linker are synthesized by synthesizing a unit having an acetal
group formed by utilizing a hydroxyl group of the low-molecular
weight model drug, and condensing the unit with a separately
synthesized activated polyethylene glycol derivative. In this case,
although it is shown that a difference in the structure around the
acetal group affects the hydrolysis rate, that is, the detaching
rate of the polyethylene glycol chain, the correlation between the
rate and the structure around the acetal group is not been
clarified so that it cannot be said that the hydrolyzability can be
controlled. Also, since the method is a method of forming an acetal
group by utilizing the hydroxyl group of the low-molecular model
drug, it is difficult to use the method in the chemical
modification of substance other than the low-molecular weight drug,
for example, protein or a drug carrier.
[0008] As described above, although there are many examples of
hydrophilic polymer derivatives each having an acetal linker
introduced into the structure for the purpose of detaching the
hydrophilic polymer chain under an acidic environment in the living
body, there is no example relating to the hydrophilic polymer
derivative in which the hydrolysis rate of the acetal linker, that
is, the detaching rate of the hydrophilic polymer chain is
accurately controlled at an arbitrary pH.
PRIOR ART DOCUMENTS
Patent Document
[0009] Patent Document 1: WO2005/108463
Non-Patent Documents
[0009] [0010] Non-Patent Document 1: 57th Annual Meeting of The
Society of Polymer Science, Japan, Preprints of The Society of
Polymer Science, Japan, 57, 1897 (May, 2008) [0011] Non-Patent
Document 2: Bioconjugate Chem. 2004, 15, 1254-1263
DISCLOSURE OF THE INVENTION
Problems that the Invention is to Solve
[0012] The deviation of pH at each portion of the living body is
very small and, for example, although the periphery of a tumor
tissue is an acidic environment in comparison with pH 7.4 in normal
tissue, the pH thereof is weakly acidic and approximately 6.0.
Also, an endosomal interior shows pH 5.5 to 6.0 and is weakly
acidic, and the endosomal interior is gradually acidified and
approaches pH 4.5 to 5.0 which is the pH of a lysosome. Since an
endosome is finally fused with a lysosome, it is required that the
drug or the like taken up in the endosome should escape from the
endosome at around pH 5.5, in order to avoid degradation thereof by
a lysosomal enzyme. Therefore, in the case where it is intended to
control in vivo/intracellular kinetics, for example, site-selective
cellular uptake and endosome escape of the drug or the like by
detaching a hydrophilic polymer chain by utilizing a slight
difference in pH at each portion of the living body, for example,
the periphery of a tumor tissue or an endosomal interior, it is
necessary to accurately control the hydrolysis rate of the acetal
linker at the pH of the weakly acidic environment in the living
body.
[0013] An object of the present invention is to provide a
hydrophilic polymer derivative having an acetal linker whose
hydrolysis rate at pH of a weakly acidic environment in the living
body can be accurately controlled, and which does not liberate a
low molecular weight substance other than the hydrophilic polymer
chain and the drug or the like connected, more specifically, a low
molecular weight aldehyde, at the time of hydrolysis.
Means for Solving the Problems
[0014] As a result of the intensive investigations to solve the
problem described above, the inventors have developed a hydrophilic
polymer derivative having a cyclic benzylidene acetal linker whose
hydrolysis rate at pH of a weakly acidic environment in the living
body can be accurately controlled, and which does not liberate a
low molecular weight substance other than the hydrophilic polymer
chain and the drug or the like connected, more specifically, a low
molecular weight aromatic aldehyde, at the time of hydrolysis.
[0015] The feature of the invention resides in that a chemically
reactive functional group and a hydrophilic polymer are connected
through a cyclic benzylidene acetal linker having substituent(s).
By appropriately selecting the kind and position of the
substituent(s) on the benzene ring of the cyclic benzylidene acetal
linker, the degrees of electron density and steric hindrance around
the acetal group which affect the hydrolysis rate of the acetal
linker can be adjusted. Based on the feature, it is possible to
impart a desired hydrolysis rate to the acetal linker and it
becomes possible to detach the hydrophilic polymer chain at an
arbitrary rate from the drug or the like which is connected to the
hydrophilic polymer derivative.
[0016] Another feature of the invention resides in that the
hydrophilic polymer and a benzene ring of the cyclic benzylidene
acetal linker are connected through a bond which is stable in the
living body. Based on the feature, the invention has an advantage
in that liberation of a low molecular weight substance other than
the hydrophilic polymer chain and the drug or the like connected,
more specifically, a low molecular weight aromatic aldehyde can be
avoided at the time of hydrolysis.
[0017] The hydrophilic polymer derivative of the invention can be
synthesized by performing a coupling reaction between a linker
compound, into which a cyclic benzylidene acetal group having
substituent(s) is introduced, and a hydrophilic polymer
intermediate. Therefore, it is not necessary to use such an excess
amount of the hydrophilic polymer for forming the acetal group as
in Patent Document 1 and the removal of the unreacted hydrophilic
polymer impurity is not required, so that it is easy to perform the
production on an industrial scale. Moreover, there is no limitation
on the kind of the acetal group which can be introduced and a
benzylidene acetal group which cannot be introduced by the
synthetic method of Non-Patent Document 1 can also be introduced.
Furthermore, unlike Non-Patent Document 2, in the hydrophilic
polymer derivative of the invention, since various functional
groups can be introduced into the terminal of the acetal linker, it
is possible to form a covalent bond with various biofunctional
molecules and drug carriers.
[0018] That is, the invention includes the following items.
[1] A hydrophilic polymer derivative having a cyclic benzylidene
acetal linker represented by formula (1):
##STR00002##
wherein R.sup.1 and R.sup.6 are each independently a hydrogen atom
or a hydrocarbon group; R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are
each independently an electron-withdrawing or electron-donating
substituent or a hydrogen atom; X.sup.1 is a chemically reactive
functional group; P is a hydrophilic polymer, s is 1 or 2, t is 0
or 1, and s+t is 1 or 2; w is an integer of 1 to 8; and Z.sup.1 and
Z.sup.2 are each independently a selected divalent spacer. [2] The
hydrophilic polymer derivative of [1], wherein s is 1 and t is 0
R.sup.2 and R.sup.5 are each a hydrogen atom, and a sum
(.SIGMA..sigma.) of substituent constants (.sigma.) in R.sup.3,
R.sup.4 and P--Z.sup.1 satisfies
-0.30.ltoreq..SIGMA..sigma..ltoreq.1.05. [3] The hydrophilic
polymer derivative of [1], wherein s is 1 and t is 0, at least one
of R.sup.2 and R.sup.5 is the substituent described above, and a
sum (.SIGMA..sigma.) of substituent constants (.sigma.) in R.sup.3,
R.sup.4 and P--Z.sup.1 satisfies
-1.71.ltoreq..SIGMA..sigma..ltoreq.0.88. [4] The hydrophilic
polymer derivative of [1], wherein s is 1 and t is 1, or s is 2 and
t is 0, R.sup.2 and R.sup.5 are each a hydrogen atom, and a sum
(.SIGMA..sigma.) of substituent constants (.sigma.) in R.sup.3,
R.sup.4 and P--Z.sup.1 satisfies
-0.19.ltoreq..SIGMA..sigma..ltoreq.0.57. [5] The hydrophilic
polymer derivative of [1], wherein s is 1 and t is 1, or s is 2 and
t is 0, at least one of R.sup.2 and R.sup.5 is the substituent
described above, and a sum (.SIGMA..sigma.) of substituent
constants (.sigma.) in R.sup.3, R.sup.4 and P--Z.sup.1 satisfies
-0.98.ltoreq..SIGMA..sigma..ltoreq.0.48. [6] The hydrophilic
polymer derivative of any one of [1] to [5], wherein X.sup.1 is
selected from the group consisting of an active ester group, an
active carbonate group, an aldehyde group, an isocyanate group, an
isothiocyanate group, an epoxy group, a maleimide group, a vinyl
sulfone group, an acryl group, a sulfonyloxy group, a carboxy
group, a thiol group, a dithiopyridyl group, an .alpha.-haloacetyl
group, an alkynyl group, an allyl group, a vinyl group, an amino
group, an oxyamino group, a hydrazide group and an azide group. [7]
The hydrophilic polymer derivative of any one of [1] to [6],
wherein X.sup.1 is selected from the group consisting of formula
(a), formula (b), formula (c), formula (d), formula (e), formula
(f), formula (g), formula (h), formula (i), formula (j), formula
(k), formula (l), formula (m) and formula (n).
##STR00003##
wherein R.sup.7 is a hydrogen atom or a sulfo group; R.sup.8 and
R.sup.11 are each independently a hydrogen atom or a hydrocarbon
group having from 1 to 5 carbon atoms; R.sup.9 is a hydrocarbon
group having from 1 to 10 carbon atoms which may contain a halogen
atom; and R.sup.10 is a halogen atom selected from a chlorine atom,
a bromine atom and an iodine atom. [8] The hydrophilic polymer
derivative of any one of [1] to [7], wherein Z.sup.1 and Z.sup.2
are each independently an ether bond, an ester bond, a carbonate
bond, a urethane bond, an amide bond, a secondary amino group, an
alkylene group containing any of these bonds and group, a single
bond or an alkylene group, and in a case where at least one of
Z.sup.1 and Z.sup.2 is an ether bond, an ester bond, a carbonate
bond, a urethane bond, an amide bond, a secondary amino group or an
alkylene group containing any of these bonds and group and a
plurality of identical structural units are connected, a number of
the structural units is 2 or less. [9] The hydrophilic polymer
derivative of any one of [1] to [8], wherein P is a linear
polyethylene glycol having a hydrocarbon group or a chemically
reactive functional group at its terminal. [10] The hydrophilic
polymer derivative of [9], wherein w is 1, and P is represented by
formula (2):
Y--(OCH.sub.2CH.sub.2).sub.n-- (2)
wherein Y is a hydrocarbon group having from 1 to 24 carbon atoms;
and n is an integer of 3 to 2,000. [11] The hydrophilic polymer
derivative of [9], wherein w is 1, and P is represented by formula
(3):
X.sup.2--Z.sup.3--(OCH.sub.2CH.sub.2).sub.n-- (3)
wherein X.sup.2 is a chemically reactive functional group different
from X.sup.1; Z.sup.3 is a divalent spacer, and n is an integer of
3 to 2,000.
[0019] The hydrophilic polymer derivative of any one of [1] to [8],
wherein P is a branched polyethylene glycol having a hydrocarbon
group or a chemically reactive functional group different from
X.sup.1 at its terminal.
[13] The hydrophilic polymer derivative of [12], wherein w is 1,
and P is represented by formula (4):
##STR00004##
wherein Y is a hydrocarbon group having from 1 to 24 carbon atoms;
n is an integer of 3 to 1,000; and v is 0 or 2. [14] The
hydrophilic polymer derivative of [12], wherein w is 1, and P is
represented by formula (5):
##STR00005##
wherein X.sup.2 is a chemically reactive functional group different
from X.sup.1; Z.sup.3 is a divalent spacer, n is an integer of 3 to
1,000; and v is 0 or 2. [15] The hydrophilic polymer derivative of
[12], wherein w is v+2, and P is represented by formula (6):
##STR00006##
wherein X.sup.2 is a chemically reactive functional group different
from X.sup.1; Z.sup.3 is a divalent spacer; n is an integer of 3 to
1,000; and v is 0 or 2. [16] The hydrophilic polymer derivative of
any one of [11], [14] and [15], wherein X.sup.2 is selected from
the group consisting of an active ester group, an active carbonate
group, an aldehyde group, an isocyanate group, an isothiocyanate
group, an epoxy group, a maleimide group, a vinyl sulfone group, an
acryl group, a sulfonyloxy group, a carboxy group, a thiol group, a
dithiopyridyl group, an .alpha.-haloacetyl group, an alkynyl group,
an allyl group, a vinyl group, an amino group, an oxyamino group, a
hydrazide group and an azide group. [17] The hydrophilic polymer
derivative of any one of [11], [14] and [15], wherein X.sup.2 is
selected from the group consisting of formula (a), formula (b),
formula (c), formula (d), formula (e), formula (f), formula (g),
formula (h), formula (i), formula (j), formula (k), formula (l),
formula (m) and formula (n):
##STR00007##
wherein R.sup.7 is a hydrogen atom or a sulfo group; R.sup.8 and
R.sup.11 are each independently a hydrogen atom or a hydrocarbon
group having from 1 to 5 carbon atoms; R.sup.9 is a hydrocarbon
group having from 1 to 10 carbon atoms which may contain a halogen
atom; and R.sup.10 is a halogen atom selected from a chlorine atom,
a bromine atom and an iodine atom. [18] The hydrophilic polymer
derivative of any one of [11], [14] and [15], wherein Z.sup.3 is an
ether bond, an ester bond, a carbonate bond, a urethane bond, an
amide bond, a secondary amino group, an alkylene group containing
any of these bonds and group, a single bond or an alkylene group,
and in a case where Z.sup.3 is an ether bond, an ester bond, a
carbonate bond, a urethane bond, an amide bond, a secondary amino
group or an alkylene group containing any of these bonds and group
and a plurality of identical structural units are connected, a
number of the structural units is 2 or less. [19] The hydrophilic
polymer derivative of any one of [1] to [8], wherein P is
polyethylene glycol having the number of terminals of 2 to 8, all
the terminals of the polyethylene glycol constituting P are each
connected to Z.sup.1, and w is equal to the number of terminals of
the polyethylene glycol. [20] The hydrophilic polymer derivative of
[19], wherein P is selected from the group consisting of formula
(r), formula (s), formula (t), formula (u) and formula (v):
##STR00008##
wherein n is an integer of 3 to 2,000, and w is 2 when P is
represented by formula (r), w is 3 when P is represented by formula
(s), w is 4 when P is represented by formula (t), w is 4 when P is
represented by formula (u), and w is 8 when P is represented by
formula (v). [21] A cyclic benzylidene acetal linker compound
represented by formula (55):
##STR00009##
wherein R.sup.1 and R.sup.6 are each independently a hydrogen atom
or a hydrocarbon group; R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are
each independently an electron-withdrawing or electron-donating
substituent or a hydrogen atom; X.sup.3 and X.sup.4, which may be
the same or different, are each a chemically reactive functional
group; s is 1 or 2, t is 0 or 1, and s+t is 1 or 2; and Z.sup.1 and
Z.sup.2 are each independently a selected divalent spacer. [22] The
cyclic benzylidene acetal linker compound of [21], wherein s is 1
and t is 0, R.sup.2 and R.sup.5 are each a hydrogen atom, and a sum
(.SIGMA..sigma.) of substituent constants (.sigma.) in R.sup.3,
R.sup.4 and X.sup.3--Z.sup.1 satisfies
-0.30.ltoreq..SIGMA..sigma..ltoreq.1.05.
[0020] The cyclic benzylidene acetal linker compound of [21],
wherein s is 1 and t is 0, at least one of R.sup.2 and R.sup.5 is
the substituent described above, and a sum (.SIGMA..sigma.) of
substituent constants (.sigma.) in R.sup.3, R.sup.4 and
X.sup.3--Z.sup.1 satisfies
-1.71.ltoreq..SIGMA..sigma..ltoreq.0.88.
[24] The cyclic benzylidene acetal linker compound of [21], wherein
s is 1 and t is 1, or s is 2 and t is 0, R.sup.2 and R.sup.5 are
each a hydrogen atom, and a sum (.SIGMA..sigma.) of substituent
constants (.sigma.) in R.sup.3, R.sup.4 and X.sup.3--Z.sup.1
satisfies -0.19.ltoreq..SIGMA..sigma..ltoreq.0.57. [25] The cyclic
benzylidene acetal linker compound of [21], wherein s is 1 and t is
1, or s is 2 and t is 0, at least one of R.sup.2 and R.sup.5 is the
substituent described above, and a sum (.SIGMA..sigma.) of
substituent constants (.sigma.) in R.sup.3, R.sup.4 and
X.sup.3--Z.sup.1 satisfies -0.98.ltoreq..SIGMA..sigma..ltoreq.0.48.
[26] The cyclic benzylidene acetal linker compound of any one of
[21] to [25], wherein X.sup.3 and X.sup.4 are each selected from
the group consisting of an active ester group, an active carbonate
group, an aldehyde group, an isocyanate group, an isothiocyanate
group, an epoxy group, a maleimide group, a vinyl sulfone group, an
acryl group, a sulfonyloxy group, a carboxy group, a thiol group, a
dithiopyridyl group, an .alpha.-haloacetyl group, an alkynyl group,
an allyl group, a vinyl group, an amino group, an oxyamino group, a
hydrazide group, an azide group and hydroxy group. [27] The cyclic
benzylidene acetal linker compound of any one of [21] to [26],
wherein X.sup.3 and X.sup.4 are each selected from the group
consisting of formula (a), formula (b), formula (c), formula (d),
formula (e), formula (f), formula (g), formula (h), formula (i),
formula (j), formula (k), formula (l), formula (m), formula (n) and
formula (o).
##STR00010##
wherein R.sup.7 is a hydrogen atom or a sulfo group; R.sup.8 and
R.sup.11 are each independently a hydrogen atom or a hydrocarbon
group having from 1 to 5 carbon atoms; R.sup.9 is a hydrocarbon
group having from 1 to 10 carbon atoms which may contain a halogen
atom; and R.sup.10 is a halogen atom selected from a chlorine atom,
a bromine atom and an iodine atom. [28] The cyclic benzylidene
acetal linker compound of any one of [21] to [27], wherein Z.sup.1
and Z.sup.2 are each independently an ether bond, an ester bond, a
carbonate bond, a urethane bond, an amide bond, a secondary amino
group, an alkylene group containing any of these bonds and group, a
single bond or an alkylene group, and in a case where at least one
of Z.sup.1 and Z.sup.2 is an ether bond, an ester bond, a carbonate
bond, a urethane bond, an amide bond, a secondary amino group or an
alkylene group containing any of these bonds and group and a
plurality of identical structural units are connected, a number of
the structural units is 2 or less. [29] The cyclic benzylidene
acetal linker compound of any one of [21] to [28], wherein the
functional group constituting any one of X.sup.3 and X.sup.4
contains a protective group.
Advantage of the Invention
[0021] In the hydrophilic polymer derivative having a cyclic
benzylidene acetal linker according to the invention, the
hydrolysis rate of the cyclic benzylidene acetal linker can be
controlled according to the pH of a weakly acidic environment in
the living body and it is possible to selectively detach the
hydrophilic polymer chain from the drug or the like connected to
the hydrophilic polymer derivative at the pH of the target portion.
Therefore, it is possible to fundamentally eliminate problems, for
example, inhibition of intracellular uptake and endosome escape
resulting from hydrated layer formation of a hydrophilic polymer
which are disadvantages of the conventional hydrophilic polymer
modification by detaching the hydrophilic polymer chain after a
biofunctional molecule or drug carrier connected to the hydrophilic
polymer derivative has been transported to the tissue or site as a
target. That is, by using the hydrophilic polymer derivative in the
chemical modification of the drug or the like, it is possible to
impart only the advantages of hydrophilic polymer modification, for
example, an increase in water solubility and bioavailability and
prolongation of circulation time in blood, without preventing the
expression of the original function of the drug or the like.
[0022] Moreover, since in the hydrophilic polymer derivative, the
hydrophilic polymer and a benzene ring of the cyclic benzylidene
acetal linker are connected through a bond which is stable in the
living body, liberation of a low molecular weight substance other
than the hydrophilic polymer chain and the drug or the like
connected, more specifically, a low molecular weight aromatic
aldehyde is avoided at the time of hydrolysis so that the influence
due to the low molecular weight substance can be eliminated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 shows results of the hydrolysis test in MES
deuterated water buffer at pD 5.5 at 37.degree. C. using the
compounds of formula (29), formula (32), formula (33), formula (35)
and formula (36) described in Examples.
[0024] FIG. 2 shows results of the hydrolysis test in HEPES
deuterated water buffer at pD 7.4 at 37.degree. C. using the
compounds of formula (29), formula (32), formula (33), formula (35)
and formula (36) described in Examples.
MODE FOR CARRYING OUT THE INVENTION
[0025] The invention will be described in detail hereinafter.
[0026] The term "acetal" as used in the specification means both of
an acetal structure derived from an aldehyde and an acetal
structure derived from a ketone, that is, a ketal structure.
[0027] The term "cyclic acetal" as used in the invention means both
of a 1,3-dioxolane structure of a 5-membered ring which is s is 1
and t is 0 in formula (1) and a 1,3-dioxane structure of a
6-membered ring which is s is 1 and t is 1 or s is 2 and t is 0 in
formula (1)
[0028] Each of R.sup.1 and R.sup.6 in formula (1) of the invention
is a hydrogen atom or a hydrocarbon group, a number of carbon atoms
of the hydrocarbon group is preferably 10 or less, and specific
examples of the hydrocarbon group include a methyl group, an ethyl
group, a propyl group, an isopropyl group, a tert-butyl group, a
phenyl group and a benzyl group. A preferred embodiment of R.sup.1
is a hydrogen atom or a methyl group, and a hydrogen atom is more
preferred.
[0029] The benzene ring in formula (1) of the invention may have a
plurality of substituents. By appropriately selecting the kind, the
position and the degree of electron-donating property and
electron-withdrawing property of the substituents on the benzene
ring, it is possible to adjust the degrees of electron density and
steric hindrance around the acetal group which affects the
hydrolysis rate of the cyclic acetal linker. This makes it possible
to import a desired hydrolysis rate to the cyclic acetal
linker.
[0030] In the specification, the substituent(s) on the benzene ring
in formula (1) is described using the "substituent constant
(.sigma.)" which means the substituent constant in the Hammett's
rule which quantifies the effect of the substituent on the reaction
rate or equilibrium of benzene derivative. However, as is known,
the Hammett's rule is applied only to a para-substituted or
meta-substituted benzene derivative and cannot be applied to an
ortho-substituted benzene derivative which is affected by steric
hindrance. Therefore, in the case of ortho-substituted benzene
derivative, the substituent constant means the substituent constant
in the Taft's equation which extends the Hammett's rule described
above.
[0031] In the para-substituted or meta-substituted benzene
derivative described above, the Hammett's rule is represented by
the following formula (7).
log(k/k.sub.0)=.rho..sigma. (7)
wherein k is a rate constant or equilibrium constant in an
arbitrary reaction of para-substituted or meta-substituted benzene
derivative, k.sub.0 is a rate constant or equilibrium constant in
the case where the benzene derivative does not have a substituent,
that is, the substituent is a hydrogen atom, .rho. is a reaction
constant, and .sigma. is a substituent constant.
[0032] The reaction constant (.phi. in formula (7) described above
is a constant which is determined depending on reaction conditions,
for example, the kind of reaction, temperature or solvent, and can
be calculated from the slope of Hammett plots. In the acid
hydrolysis reaction of the hydrophilic polymer derivative having a
cyclic benzylidene acetal linker of the invention, in the case of
1,3-dioxolane structure, the constant is calculated as ".rho.=-2.7"
from the results of the hydrolysis tests performed for the
compounds of formula (29), formula (32) and formula (33) described
in Examples. Also, in the case of 1,3-dioxane structure, the
constant is calculated as ".rho.=-4.8" from the results of the
hydrolysis tests performed for the compounds of formula (35) and
formula (36).
[0033] The substituent constant (.sigma.) in formula (7) described
above is a constant which is determined only depending on the kind
and position of the substituent regardless of the kind of reaction.
In the case where no substituent is present, that is, the
substituent is a hydrogen atom, the constant is "0". The term
"electron-withdrawing" as used in the specification means the case
where .sigma. is a positive value and the term "electron-donating"
means the case where .sigma. is a negative value.
[0034] As described above, the Hammett's rule is applied only to
para-substituted or meta-substituted benzene derivative and cannot
be applied to the case of ortho-substituted benzene derivative
which is affected by steric hindrance. Therefore, it is the Taft's
equation that the effect of such steric hindrance is introduced as
a factor of the position, that is, a position constant (Es) of the
substituent, to extend the Hammett's rule so that it can also be
applied to the case of the ortho-substituted benzene derivative.
The Taft's equation is represented by the following formula
(8).
log(k/k.sub.0)=.rho.*.sigma.*+Es (8)
wherein k is a rate constant or equilibrium constant in an
arbitrary reaction of para-substituted or meta-substituted benzene
derivative, k.sub.0 is a rate constant or equilibrium constant in
the case where the benzene derivative does not have a substituent,
that is, the substituent is a hydrogen atom, .rho.* is a reaction
constant, .sigma.* is a substituent constant, and Es is a position
constant of the substituent.
[0035] As is known, since the reaction constant (.rho.) of
para-substituted or meta-substituted benzene derivative and the
reaction constant (.rho.*) of ortho-substituted benzene derivative
are approximately equal, it is defined in the specification that
.rho. and .rho.* are the same. Since the substituent constant
(.sigma.*) in the ortho position is similar to the substituent
constant in the para position as described, for example, in
"Charton, M. Can. J. Chem. 1960, 38, 2493-2499", to the substituent
constant in the ortho position in the specification is applied a
corresponding substituent constant in the par position.
[0036] The substituent constant (.sigma.) in the para position or
the meta position is described in "Hansch, C.; Leo, A.; Taft. R. W.
Chem. Rev. 1991, 91, 165-195", and with respect to a substituent in
which the substituent constant (.sigma.) is unknown the constant
can be measured and determined by the method described in "Hammett,
L. P. Chem. Rev. 1935, 17(1), 125-136". Moreover, the position
constant (Es) is described in "Unger, S. H.; Hansch, C. Prog. Phys.
Org. Chem. 1976, 12, 91-118". However, as to Es as used in the
specification, a hydrogen atom is defined as "0".
[0037] In formula (1), in the case where a plurality of
substituents are present on the benzene ring, it is defined that
additivity is established for the substituent constant (.sigma.)
and the position constant (Es) thereof, and the sum of a is
represented by ".SIGMA..sigma." and the sum of Es is represented by
".SIGMA.Es".
[0038] Z.sup.1 is connected to the benzene ring of the cyclic
benzylidene acetal and P--Z.sup.1 is also a substituent of the
benzene ring. The substituent constant of P--Z.sup.1 can be
determined by separately measuring the composition and
polymerization degree of P and combination thereof with Z.sup.1,
but, since the substituent constant of P--Z.sup.1 is substantially
affected largely by the structure in the vicinity of the connecting
portion to the benzene ring, the effect of the other portions is so
small as to be ignored. Therefore, it is possible to use a known
substituent constant of a structure similar to the structure in the
vicinity of the connecting portion to the benzene ring in place of
separately measuring the substituent constant as to P--Z.sup.1.
[0039] It is defined that the substituent constant of P--Z.sup.1 in
the specification can be substituted with a substituent constant of
a structure in which atom(s) other than the second atom connected
to the third atom counted from the atom connected to the benzene
ring the backbone atoms of the main chain of P--Z.sup.1 are
substituted with hydrogen atom(s). However, in the case where, when
the atom is substituted with a hydrogen atom, a carboxy group is
formed, it is defined that the substituent constant of P--Z.sup.1
can be substituted with a substituent constant of a structure in
which the atom is substituted with a methyl group in place of a
hydrogen atom.
[0040] Specific examples of the structure of the connecting portion
to the benzene ring in P--Z.sup.1 and the structure for the
substitution are shown below. In the case of (r1) shown below,
wherein the connecting portion to the benzene ring in P--Z.sup.1 is
an ether bond, a substituent constant of (r2) shown below is
applied. In the cases of (r3) and (r5) shown below, wherein the
connecting portion to the benzene ring in P--Z.sup.1 is an amide
bond, substituent constants of (r4) and (r6) shown below are
applied, respectively. In the case of (r7) shown below, wherein the
connecting portion to the benzene ring in P--Z.sup.1 is a urethane
bond, a substituent constant of (r8) shown below is applied.
TABLE-US-00001 Structure of Connecting Portion to Benzene Ring
Structure for Substitution (r1) ##STR00011## (r2) ##STR00012## (r3)
##STR00013## (r4) ##STR00014## (r5) ##STR00015## (r6) ##STR00016##
(r7) ##STR00017## (r8) ##STR00018##
[0041] As to the appropriate hydrolysis rate of the hydrophilic
polymer derivative having a cyclic benzylidene acetal linker of the
invention, hydrolysis half-life (t.sub.1/2) in a buffer at pH 5.5
and 37.degree. C. is preferably in the range from 1 hour to 6
months, more preferably in the range from 1 hour to 1 month, and
still more preferably in the range from 1 hour to 24 hours. In the
specification, using a numerical value derived from the compound of
formula (32) described in Examples in which t.sub.1/2 under the
hydrolysis conditions described above is 12 hours, a suitable range
of the sum (.SIGMA..sigma.) of substituent constants in the case
where a 1,3-dioxolane structure is included is defined. When
log(k/k.sub.0) for the compound of formula (32) is calculated using
equation (7) above, the following equation (9) is obtained.
However, as defined above, P--Z.sup.1 in the compound of formula
(32) is substituted with an ethoxy group (CH.sub.3CH.sub.2O--).
log(k/k.sub.0)=-2.7.times.(0.34-0.24)=-0.27 (9)
[0042] In the case where R.sup.2 and R.sup.5 in formula (1) are
hydrogen atoms, when log(k'/k.sub.0) is calculated by taking the
rate constant at the time when t.sub.1/2 is 24 hours as k' using
equation (9) and equation (7) above, the following equation (10) is
obtained.
log(k'/k)=log {(12/24)k/k)}=-0.30
[0043] When the equation is modified,
log(k'/k)=log [(k'/k.sub.0)/(k/k.sub.0)]=-0.30
log(k'/k.sub.0)-log(k/k.sub.0)=-0.30
[0044] When equation (9) above is substituted,
log(k'/k.sub.0)-(-0.27)=-030
log(k'/k.sub.0)=-0.57 (10)
[0045] Here, when the sum (.SIGMA..sigma.) of the substituent
constants is calculated using equation (10) and equation (7) above,
the following equation (11) is obtained.
log(k'/k.sub.0)=-2.7.times..SIGMA..sigma.=-0.57
.SIGMA..sigma.=0.21 (11)
[0046] Similarly, in the case where R.sup.2 and R.sup.5 in formula
(1) are hydrogen atoms, when log(k''/k.sub.0) is calculated by
taking the rate constant at the time when t.sub.1/2 is 1 hour as
k'', the following equation (12) is obtained.
log(k''/k)=log(12k/k}=1.08
[0047] When the equation is modified,
log(k''/k)=log [(k''/k.sub.0)/(k/k.sub.0)]=1.08
log(k''/k.sub.0)-log(k/k.sub.0)=1.08
[0048] When equation (9) above is substituted,
log(k''/k.sub.0)-(-0.27)=1.08
log(k''/k.sub.0)=0.81 (12)
[0049] Here, when the sum (.SIGMA..sigma.) of the substituent
constants is calculated using equation (12) and equation (7) above,
the following equation (13) is obtained.
log(k''/k.sub.0)=-2.7.times..SIGMA..sigma.=0.81
.SIGMA..sigma.=-0.30 (13)
[0050] From equation (11) and equation (13), in the case where
formula (1) includes a 1,3-dioxolane structure and R.sup.2 and
R.sup.5 are hydrogen atoms, when the range of .SIGMA..sigma.
satisfies -0.30.ltoreq..SIGMA..sigma..ltoreq.0.21, t.sub.1/2 of the
hydrophilic polymer derivative is represented by 1
hour.ltoreq.t.sub.1/2.ltoreq.24 hours. Similarly, when the ranges
of .SIGMA..sigma. at 1 hour.ltoreq.t.sub.1/2.ltoreq.1 month and 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months are calculated,
-0.30.ltoreq..SIGMA..sigma..ltoreq.0.76 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.1 month and
-0.30.ltoreq..SIGMA..sigma..ltoreq.1.05 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months, respectively.
[0051] The substituent which can be used in the invention is a
substituent which does not inhibit the acetalization reaction of
the cyclic benzylidene acetal linker compound, the coupling
reaction of the cyclic benzylidene acetal linker compound with the
hydrophilic polymer intermediate and the terminal functional group
conversion reaction of the hydrophilic polymer derivative in the
synthesis process of the hydrophilic polymer derivative, and
further the bond-forming reaction between the hydrophilic polymer
derivative and the drug or the like.
[0052] The substituent may be any of electron-withdrawing
substituent and electron-donating substituent as far as it
satisfies the conditions described above, and the substituents may
be used individually or in combination. The electron-withdrawing
substituent includes an acyl group having from 2 to 5 carbon atoms,
an alkoxycarbonyl group having from 2 to 5 carbon atoms, a
carbamoyl group having from 2 to 5 carbon atoms, an acyloxy group
having from 2 to 5 carbon atoms, an acylamino group having from 2
to 5 carbon atoms, an alkoxycarbonylamino group having from 2 to 5
carbon atoms, a fluorine atom, a chlorine atom, a bromine atom, an
iodine atom, an alkylsulfanyl group having from 1 to 4 carbon
atoms, an alkylsulfonyl group having from 1 to 4 carbon atoms, an
arylsulfonyl group having from 6 to 10 carbon atoms, a nitro group,
a trifluoromethyl group and a cyano group, and preferred examples
thereof include an acetyl group, a methoxycarbonyl group, a
methylcarbamoyl group, an acetoxy group, an acetamide group, a
methoxycarbonylamino group, a fluorine atom, a chlorine atom, a
bromine atom, an iodine atom, a methylsulfanyl group, a
phenylsulfonyl group, a nitro group, a trifluoromethyl group and a
cyano group. The electron-donating substituent includes an alkyl
group having from 1 to 4 carbon atoms, and preferred examples
thereof include a methyl group, an ethyl group, a propyl group, an
isopropyl group and a tert-butyl group. The substituent which is an
electron-withdrawing group in the meta-position and an
electron-donating group in the para-position and ortho-position
includes an alkoxy group having from 1 to 4 carbon atoms, an aryl
group having from 6 to 10 carbon atom and an aryloxy group having
from 6 to 10 carbon atoms, and preferred examples thereof include a
methoxy group, an ethoxy group, a propoxy group, an isopropoxy
group, a tert-butoxy group, a phenyl group and a phenoxy group.
[0053] In the case where formula (1) includes a 1,3-dioxolane
structure and at least one of R.sup.2 and R.sup.5 is a substituent
other than a hydrogen atom, using the position constants (Es) of a
phenyl group which has the largest influence of steric hindrance
and a fluorine atom which has the smallest influence of steric
hindrance among the substituents described above, the ranges of
.SIGMA..sigma. in a buffer at pH 5.5 and 37.degree. C. at 1
hour.ltoreq.t.sub.1/2.ltoreq.24 hours, 1
hour.ltoreq.t.sub.1/2.ltoreq.1 month, and 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months are calculated by using
Taft's equation (8), respectively. As a result, it is found that
-1.71.ltoreq..SIGMA..sigma..ltoreq.0.04 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.24 hours,
-1.71.ltoreq..SIGMA..sigma..ltoreq.0.59 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.1 month, and
-1.71.ltoreq..SIGMA..sigma..ltoreq.0.88 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months, respectively.
[0054] In the case where formula (1) includes a 1,3-dioxolane
structure and R.sup.2 and R.sup.5 are hydrogen atoms, for example,
a preferred embodiment which satisfies
-0.30.ltoreq..SIGMA..sigma..ltoreq.0.21 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.24 hours is described below. However,
the substituents shown herein means R.sup.3 and R.sup.4 and the
structure used in place of P--Z.sup.1 according to the definition
described above. In the preferred embodiment, one of the
meta-positions in formula (1) is a methoxy group, an ethoxy group
or an acetamide group, and more preferably an ethoxy group or an
acetamide group. In another preferred embodiment, the para-position
in formula (1) is a methoxy group or an ethoxy group and one of the
meta-positions is a substituent independently selected from the
group consisting of a fluorine atom, a chlorine atom, a bromine
atom and an iodine atom, and more preferably the para-position is
an ethoxy group and one of the meta-positions is a fluorine atom or
a chlorine atom. In still another preferred embodiment, one of the
para-position and the meta-position in formula (1) is a methoxy
group, an ethoxy group or an acetamide group, and more preferably a
methoxy group or an ethoxy group.
[0055] Further, in the case where formula (1) includes a
1,3-dioxolane structure and at least one of R.sup.2 and R.sup.5 is
a substituent other than a hydrogen atom, for example, a preferred
embodiment which satisfies -1.71.ltoreq..SIGMA..sigma..ltoreq.0.04
at the time of 1 hour.ltoreq.t.sub.1/2.ltoreq.24 hours is described
below. However, the substituents shown herein means R.sup.3 and
R.sup.4 and the structure used in place of P--Z.sup.1 according to
the definition described above. In the case where one of R.sup.2
and R.sup.5 in formula (1) is a fluorine atom, a methyl group or an
ethyl group and the other is a hydrogen atom, the para-position is
preferably an ethoxy group or an acetamide group, and more
preferably an ethoxy group. In the case where one of R.sup.2 and
R.sup.5 in formula (1) is a methoxy group and the other is a
hydrogen atom, the para-position is preferably a substituent
selected from the group consisting of a methoxymethyl group and an
acetamide group, and more preferably an acetamide group.
[0056] Moreover, using a numerical value derived from the compound
of formula (35) described in Examples in which the hydrolysis
half-life (t.sub.1/2) in a buffer at pH 5.5 and 37.degree. C. is 24
hours, a suitable range of the sum (.SIGMA..sigma.) of substituent
constants in the case where formula (1) includes a 1,3-dioxane
structure can be defined.
[0057] In the case where formula (1) includes a 1,3-dioxane
structure and R.sup.2 and R.sup.5 are hydrogen atoms, when the
range of .SIGMA..sigma. satisfies
-0.19.ltoreq..SIGMA..sigma..ltoreq.0.10, t.sub.1/2 of the
hydrophilic polymer derivative is represented by 1
hour.ltoreq.t.sub.1/2.ltoreq.24 hours. Similarly, when the ranges
of .SIGMA..sigma. at 1 hour.ltoreq.t.sub.1/2.ltoreq.1 month and 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months are calculated,
-0.19.ltoreq..SIGMA..sigma..ltoreq.0.41 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.1 month and
-0.19.ltoreq..SIGMA..sigma..ltoreq.0.57 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months, respectively.
[0058] Further, in the case where formula (1) includes a
1,3-dioxone structure and at least one of R.sup.2 and R.sup.5 is a
substituent other than a hydrogen atom, using the position
constants (Es) of a phenyl group which has the largest influence of
steric hindrance and a fluorine atom which has the smallest
influence of steric hindrance among the substituents described
above, the ranges of .SIGMA..sigma. in a buffer at pH 5.5 and
37.degree. C. at 1 hour.ltoreq.t.sub.1/2.ltoreq.24 hours, 1
hour.ltoreq.t.sub.1/2.ltoreq.1 month, and 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months are calculated by using
Taft's equation (8), respectively. As a result, it is found that
-0.98.ltoreq..SIGMA..sigma..ltoreq.0.00 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.24 hours,
-0.98.ltoreq..SIGMA..sigma..ltoreq.0.31 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.1 month, and
-0.98.ltoreq..SIGMA..sigma..ltoreq.0.48 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months, respectively.
[0059] As described above, the kind and position of the
substituent(s) suitable for imparting the desired hydrolyzability
to the hydrophilic polymer derivative having a cyclic benzylidene
acetal linker of the invention can be reasonably set by performing
the calculation described above using equation (7) and equation
(8).
[0060] X.sup.1 in formula (1) of the invention is not particularly
limited as long as it is a functional group which forms a covalent
bond upon a reaction with a functional group present in a
biofunctional molecule, for example, a physiologically active
protein, peptide, an antibody, a nucleic acid or a low molecular
drug, or a drug carrier, for example, a liposome or a polymer
micelle, which is the object of chemical modification. For example,
the functional groups include those described in "Harris, J. M.
Poly(Ethylene Glycol) Chemistry; Plenum Press: New York. 1992",
"Hermanson, G. T. Bioconjugate Techniques, 2nd ed.; Academic Press:
San Diego, Calif., 2008", "PEGylated Protein Drugs: Basic Science
and Clinical Applications; Veronese, F. M., Ed.; Birkhauser: Basel,
Switzerland, 2009" and the like.
[0061] Preferred examples of X.sup.1 include an active ester group,
an active carbonate group, an aldehyde group, an isocyanate group,
an isothiocyanate group, an epoxy group, a maleimide group, a vinyl
sulfone group, an acryl group, a sulfonyloxy group, a carboxy
group, a thiol group, a dithiopyridyl group, an .alpha.-haloacetyl
group, an alkynyl group, an allyl group, a vinyl group, an amino
group, an oxyamino group, a hydrazide group and an azide group.
More specifically, the functional group capable of forming a
covalent bond upon a reaction with an amino group of the
biofunctional molecule is an active ester group, an active
carbonate group, an aldehyde group, an isocyanate group, an
isothiocyanate group, an epoxy group, a maleimide group, a vinyl
sulfone group, an acryl group, a sulfonyloxy group or a carboxy
group, the functional group capable of forming a covalent bond upon
a reaction with a thiol group of the biofunctional molecule is an
active ester group, an active carbonate group, an aldehyde group,
an isocyanate group, an isothiocyanate group, an epoxy group, a
maleimide group, a vinyl sulfone group, an acryl group, a
sulfonyloxy group, a carboxy group, a thiol group, a dithiopyridyl
group, an .alpha.-haloacetyl group, an alkynyl group, an allyl
group or a vinyl group, the functional group capable of forming a
covalent bond upon a reaction with an aldehyde group or a carboxy
group of the biofunctional molecule is a thiol group, an amino
group, an oxyamino group or a hydrazide group, the functional group
capable of forming a covalent bond upon a reaction with an alkynyl
group of the biofunctional molecules is a thiol group or an azide
group, and the functional group capable of forming a covalent bond
upon a reaction with an azide group of the biofunctional molecule
is an alkynyl group.
[0062] The term "active ester" as referred to herein indicates an
activated carboxy group represented by formula: --C(.dbd.O)-L,
wherein L represents a leaving group. The leaving group represented
by L includes a succinimidyloxy group, a phthalimidyloxy group, a
4-nitrophenoxy group, a 1-imidazolyl group, a pentafluorophenoxy
group, a benzotriazol-1-yloxy group, a 7-azabenzotriazol-1-yloxy
group and the like. The term "active carbonate" as referred to
herein indicates an activated carbonate group represented by
formula --O--C(.dbd.O)-L, wherein L represents a leaving group same
as described above.
[0063] In a preferred embodiment of the invention, X.sup.1 is a
group represented by group (I), group (II), group (III), group (IV)
or group (V).
Group (I): Functional group capable of forming a covalent bond upon
a reaction with an amino group of the biofunctional molecule
[0064] (a), (b), (c), (d) (e) and (f) shown below:
Group (II): Functional group capable of forming a covalent bond
upon a reaction with a thiol group of the biofunctional
molecule
[0065] (a), (b), (c), (d), (e), (f), (g), (h), (i) and (j) shown
below:
Group (III): Functional group capable of forming a covalent bond
upon a reaction with an aldehyde group or a carboxy group of the
biofunctional molecule
[0066] (g), (k), (l) and (m) shown below:
Group (IV): Functional group capable of forming a covalent bond
upon a reaction with an alkynyl group of the biofunctional
molecule
[0067] (g), (k), (l), (m) and (n) shown below:
Group (V): Functional group each capable of forming a covalent bond
upon a reaction with an azide group of the biofunctional
molecule
[0068] (j) shown below:
##STR00019##
[0069] In the formulae above, R.sup.7 is a hydrogen atom or a sulfo
group, specific examples of the sulfo group include sodium
sulfonate and potassium sulfonate, and R.sup.7 is preferably a
hydrogen atom. R.sup.8 and R.sup.11 are each a hydrogen atom or a
hydrocarbon group having from 1 to 5 carbon atoms, and specific
examples of the hydrocarbon group include a methyl group, an ethyl
group, a propyl group, an isopropyl group, a butyl group, a
tert-butyl group and a pentyl group. R.sup.9 is a hydrocarbon group
having from 1 to 10 carbon atoms which may contain a halogen atom,
specific examples of the hydrocarbon group include a methyl group,
an ethyl group, a propyl group, an isopropyl group, a butyl group,
a tert-butyl group, a pentyl group, an isopentyl group, a hexyl
group, a benzyl group, a 4-methylphenyl group, a trifluoromethyl
group, a 2,2,2-trifluoroethyl group, a 4-(trifluoromethoxy)phenyl
group, a vinyl group, a chloroethyl group, a bromoethyl group and
an iodoethyl group, and R.sup.9 is preferably a methyl group, a
vinyl group, a 4-methylphenyl group or a 2,2,2-trifluoroethyl
group. R.sup.10 is a halogen atom selected from a chlorine atom, a
bromine atom and an iodine atom.
[0070] Z.sup.1 in formula (1) of the invention is a divalent spacer
between the benzene ring of the cyclic benzylidene acetal group and
the hydrophilic polymer chain, and Z.sup.2 is a divalent spacer
between the functional group X.sup.1 and the cyclic benzylidene
acetal group. These are composed of covalent bonds, are not
particularly limited as long as they are more stable to acid
hydrolysis than the cyclic benzylidene acetal group, and are
preferably an ether bond, an ester bond, a carbonate bond, a
urethane bond, an amide bond, a secondary amino group, an alkylene
group containing any of these bonds and group, a single bond or an
alkylene group. The number of carbon atoms of the alkylene group is
preferably from 1 to 24. By way of illustration and without
limitation, preferred examples of the alkylene group include
structures such as (z1). Preferred examples of the alkylene group
having an ether bond include structures such as (z2) or (z3).
Preferred examples of the alkylene group having an ester bond
include structures such as (z4). Preferred examples of the alkylene
group having a carbonate bond include structures such as (z5).
Preferred examples of the alkylene group having a urethane bond
include structures such as (z6). Preferred examples of the alkylene
group having an amide bond include structures such as (z7).
Preferred examples of the alkylene group having a secondary amino
group include structures such as (z8). In a preferred embodiment, p
and q are each independently an integer of 1 to 12. For example, in
the case where it is intended to connect the functional group
X.sup.1 in a hydrophobic environment, for example, the inside of a
protein, p and q are preferably large, and in the case where it is
intended to connect it in a hydrophilic environment, p and q are
preferably small. However, in the case where at least one of
Z.sup.1 and Z.sup.2 is an ether bond, an ester bond, a carbonate
bond, a urethane bond, an amide bond, a secondary amino group or an
alkylene group containing any of these bonds and group and a
plurality of identical structural units are connected, a number of
the structural units described above is 2 or less.
##STR00020##
[0071] P in formula (1) of the invention is a hydrophilic polymer
and specific examples thereof include polyalkylene glycol,
polyoxazoline, polycarbonate, polyurethane, polyvinyl alcohol,
polyacrylate, polymethacrylate, polyacrylamide,
polyvinylpyrrolidone, polylactic acid, polyglycolic acid, polyamino
acid and copolymers derived from the polymers described above, and
P is preferably polyalkylene glycol, and more preferably
polyethylene glycol.
[0072] The term "polyethylene glycol" as used in the specification
means both of polyethylene glycol having a molecular weight
distribution obtained by polymerization of ethylene oxide and a
monodispersed polyethylene glycol obtained by connecting of an
oligoethylene glycol having a single molecular weight by a coupling
reaction.
[0073] In one aspect of the invention, P in formula (1) is a linear
polyethylene glycol.
[0074] In a preferred embodiment of the aspect, P in formula (1) is
represented by formula (2).
Y--(OCH.sub.2CH.sub.2).sub.n-- (2)
[0075] In the formula, n is the number of repeating units per
polyethylene glycol chain, and in the polyethylene glycol having a
molecular weight distribution, it is defined that n is calculated
by various theoretical calculations based on a number average
molecular weight (Mn) of the compound.
[0076] In the formula, Y is a hydrocarbon group having from 1 to 24
carbon atoms, specific examples thereof include a methyl group, an
ethyl group, a propyl group, an isopropyl group, a butyl group, a
tert-butyl group, a pentyl group, an isopentyl group, a hexyl
group, a heptyl group, a 2-ethylhexyl group, an octyl group, a
nonyl group, a decyl group, an undecyl group, a dodecyl group, a
tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl
group, a heptadecyl group, an octadecyl group, a nonadecyl group,
an eicosyl group, a heneicosyl group, a docosyl group, a toicosyl
group, a tetracosyl group, a phenyl group, a benzyl group, a cresyl
group, a butylphenyl group, a dodecylphenyl group and a trityl
group, and Y is preferably a hydrocarbon group having from 1 to 10
carbon atoms, more preferably a methyl group or an ethyl group, and
still more preferably a methyl group.
[0077] In another preferred embodiment of the aspect, P in formula
(1) is represented by formula (3).
X.sup.2--Z.sup.3--(OCH.sub.2CH.sub.2).sub.n-- (3)
[0078] In the formula, X.sup.2 is a chemically reactive functional
group different from X.sup.1, and Z.sup.3 is a divalent spacer
between the functional group X.sup.2 and the polyethylene glycol
chain. Since the polyethylene glycol derivative has two different
chemically reactive functional groups X.sup.1 and X.sup.2, it is
possible to provide a polyethylene glycol-drug conjugate having a
target-directing property, for example, by connecting a drug to
X.sup.1 and connecting a target-directing molecule to X.sup.2.
[0079] Preferred examples of X.sup.2 include an active ester group,
an active carbonate group, an aldehyde group, an isocyanate group,
an isothiocyanate group, an epoxy group, a maleimide group, a vinyl
sulfone group, an acryl group, a sulfonyloxy group, a carboxy
group, a thiol group, a dithiopyridyl group, an .alpha.-haloacetyl
group, an alkynyl group, an allyl group, a vinyl group, an amino
group, an oxyamino group, a hydrazide group and an azide group.
More specifically, the functional group capable of forming a
covalent bond upon a reaction with an amino group of the
biofunctional molecule is an active ester group, an active
carbonate group, an aldehyde group, an isocyanate group, an
isothiocyanate group, an epoxy group, a maleimide group, a vinyl
sulfone group, an acryl group, a sulfonyloxy group or a carboxy
group, the functional group capable of forming a covalent bond upon
a reaction with a thiol group of the biofunctional molecule is an,
active ester group, an active carbonate group, an aldehyde group,
an isocyanate group, an isothiocyanate group, an epoxy group, a
maleimide group, a vinyl sulfone group, an acryl group, a
sulfonyloxy group, a carboxy group, a thiol group, a dithiopyridyl
group, an .alpha.-haloacetyl group, an alkynyl group, an allyl
group or a vinyl group, the functional group capable of forming a
covalent bond upon a reaction with an aldehyde group or a carboxy
group of the biofunctional molecule is a thiol group, an amino
group, an oxyamino group or a hydrazide group, the functional group
capable of forming a covalent bond upon a reaction with an alkynyl
group of the biofunctional molecule is a thiol group or an azide
group, and the functional group capable of forming a covalent bond
upon a reaction with an azide group of the biofunctional molecule
is an alkynyl group.
[0080] In a preferred embodiment of the invention. X.sup.2 is a
group represented by group (1), group (II), group (III), group (IV)
or group (V).
Group (I): Functional group capable of forming a covalent bond upon
a reaction with an amino group of the biofunctional molecule
[0081] (a), (b), (c), (d), (e) and (f) shown below:
Group (II): Functional group capable of forming a covalent bond
upon a reaction with a thiol group of the biofunctional
molecule
[0082] (a), (b), (c), (d), (e), (f), (g), (h), (i) and (j) shown
below:
Group (III): Functional group capable of forming a covalent bond
upon a reaction with an aldehyde group or a carboxy group of the
biofunctional molecule
[0083] (g), (k), (l) and (m) shown below:
Group (IV): Functional group capable of forming a covalent bond
upon a reaction with an alkynyl group of the biofunctional
molecule
[0084] (g), (k), (l), (m) and (n) shown below:
Group (V): Functional group each capable of forming a covalent bond
upon a reaction with an azide group of the biofunctional
molecule
[0085] (j) shown below:
##STR00021##
[0086] In the formulae above, R.sup.7 is a hydrogen atom or a sulfo
group, specific examples of the sulfo group include sodium
sulfonate and potassium sulfonate, and R.sup.7 is preferably a
hydrogen atom. R.sup.8 and R.sup.11 are each a hydrogen atom or a
hydrocarbon group having from 1 to 5 carbon atoms, and specific
examples of the hydrocarbon group include a methyl group, an ethyl
group, a propyl group, an isopropyl group, a butyl group, a
tert-butyl group and a pentyl group. R.sup.9 is a hydrocarbon group
having from 1 to 10 carbon atoms which may contain a halogen atom,
specific examples of the hydrocarbon group include a methyl group,
an ethyl group, a propyl group, an isopropyl group, a butyl group,
a tert-butyl group, a pentyl group, an isopentyl group, a hexyl
group, a benzyl group, a 4-methylphenyl group, a trifluoromethyl
group, a 2,2,2-trifluoroethyl group, a 4-(trifluoromethoxy)phenyl
group, a vinyl group, a chloroethyl group, a bromoethyl group and
an iodoethyl group, and R.sup.9 is preferably a methyl group, a
vinyl group, a 4-methylphenyl group or a 2,22-trifluoroethyl group.
R.sup.10 is a halogen atom selected from a chlorine atom, a bromine
atom and an iodine atom.
[0087] It is necessary that X.sup.2 is different from X.sup.1. As
to preferred examples of a combination of X.sup.1 and X.sup.2, when
X.sup.1 is an active ester group or an active carbonate group,
X.sup.2 is a group selected from a maleimide group, a vinyl sulfone
group, an .alpha.-haloacetyl group, an alkynyl group and an azide
group; when X.sup.1 is an aldehyde group, X.sup.2 is a group
selected from a maleimide group, a vinyl sulfone group, an alkynyl
group and an azide group; when X.sup.1 is a maleimide group, a
vinyl sulfone group or an .alpha.-haloacetyl group, X.sup.2 is a
group selected from an active ester group, an active carbonate
group, an alkynyl group and an azide group; when X.sup.1 is an
alkynyl group or an azide group. X.sup.2 is a group selected from a
maleimide group, a vinyl sulfone group, an .alpha.-haloacetyl
group, an active ester group, an active carbonate group, an amino
group and an oxyamino group; when X.sup.1 is an amino group or an
oxyamino group, X.sup.2 is an alkynyl group, an azide group, a
thiol group or a carboxy group; and when X.sup.1 is a thiol group,
X.sup.2 is a group selected from an amino group, an oxyamino group,
an azide group and a carboxy group. More preferably, when X.sup.1
is an active ester group or an active carbonate group, X.sup.2 is a
group selected from a maleimide group, an .alpha.-haloacetyl group,
an alkynyl group and an azide group; when X.sup.1 is an aldehyde
group, X.sup.2 is a group selected from a maleimide group, an
.alpha.-haloacetyl group, an alkynyl group and an azide group; when
X.sup.1 is a maleimide group or an .alpha.-haloacetyl group,
X.sup.2 is a group selected from an active ester group, an active
carbonate group, an alkynyl group and an azide group; when X.sup.1
is an alkynyl group or an azide group, X.sup.2 is a group selected
from a maleimide group, an .alpha.-haloacetyl group, an active
ester group, an active carbonate group, an amino group and an
oxyamino group; when X.sup.1 is an amino group or an oxyamino
group, X.sup.2 is an alkynyl group, an azide group or a thiol
group; and when X.sup.1 is a thiol group, X.sup.2 is a group
selected from an amino group, an oxyamino group and an azide
group.
[0088] Z.sup.3 is composed of covalent bonds, is not particularly
limited as long as it is more stable to acid hydrolysis than the
cyclic benzylidene acetal group, and is preferably an ether bond,
an ester bond, a carbonate bond, a urethane bond, an amide bond, a
secondary amino group, an alkylene group containing any of these
bonds and group, a single bond or an alkylene group. The number of
carbon atoms of the alkylene group is preferably from 1 to 24. By
way of illustration and without limitation, preferred examples of
the alkylene group include structures such as (z1). Preferred
examples of the alkylene group having an ether bond include
structures such as (z2) or (z3). Preferred examples of the alkylene
group having an ester bond include structures such as (z4).
Preferred examples of the alkylene group having a carbonate bond
include structures such as (z5). Preferred examples of the alkylene
group having a urethane bond include structures such as (z6).
Preferred examples of the alkylene group having an amide bond
include structures such as (z7). Preferred examples of the alkylene
group having a secondary amino group include structures such as
(z8). In a preferred embodiment, p and q are each independently an
integer of 1 to 12. For example, in the case where it is intended
to connect the functional group X.sup.2 in a hydrophobic
environment, for example, the inside of a protein, p and q are
preferably large, and in the case where it is intended to connect
it in a hydrophilic environment, p and q are preferably small.
However, in the case where Z.sup.3 is an ether bond, an ester bond,
a carbonate bond, a urethane bond, an amide bond, a secondary amino
group or an alkylene group containing any of these bonds and group
and a plurality of identical structural units are connected, a
number of the structural units described above is 2 or less.
##STR00022##
[0089] In another aspect of the invention, P in formula (1) is a
branched polyethylene glycol.
[0090] In a preferred embodiment of the aspect, P in formula (1) is
represented by formula (4).
##STR00023##
[0091] In the formula, Y is a hydrocarbon group having from 1 to 24
carbon atoms as described above, and v is 0 or 2.
[0092] In the case where v is 0, two polyethylene glycol chains are
present and, in the case where v is 2, four polyethylene glycol
chains are present. In general, in the chemical modification of a
bio-related substance with polyethylene glycol, when connecting
points to the polyethylene glycol are introduced more than
necessary, the active sites of the bio-related substance are
destroyed to reduce its function so that an attempt to increase the
effect by increasing a molecular weight of the polyethylene glycol
has been performed. However, the viscosity increases with the
increase in the molecular weight and hence, for example, handling
as an aqueous solution preparation, for example, an injection
preparation becomes difficult. Since the polyethylene glycol
derivative has a branched structure, it shows low viscosity in
comparison with a linear polyethylene glycol derivative having the
same molecular weight, and thus it is useful in application, for
example, the aqueous solution preparation.
[0093] In another preferred embodiment of the aspect, P in formula
(1) is represented by formula (5).
##STR00024##
[0094] In the formula, X.sup.2 is a chemically reactive functional
group different from X.sup.1 as described above, Z.sup.3 is a
divalent spacer as described above, and v is 0 or 2.
[0095] The polyethylene glycol derivative has one X.sup.1 and two
or four X.sup.2 and, for example, when a drug is connected to
X.sup.1 and a target-directing molecule is connected to X.sup.2,
high target-directing performance can be obtained.
[0096] In still another preferred embodiment of the aspect, P in
formula (1) is represented by formula (6).
##STR00025##
[0097] In the formula, X.sup.2 is a chemically reactive functional
group different from X.sup.1 as described above, Z.sup.3 is a
divalent spacer as described above, and v is 0 or 2.
[0098] In the antibody-drug conjugate (ADC)-related field, in order
to increase drug transportation efficiency, it is preferred to
connect a plurality of drugs to an antibody, but when a plurality
of connecting points are introduced into the antibody, a problem
arises in that the affinity to an antigen is decreased. The
polyethylene glycol derivative has two or four X.sup.1 and one
X.sup.2, and, for example, when an anticancer agent is connected to
X.sup.1 and an antibody is connected to X.sup.2 in ADC targeting
cancer, it is possible to improve the transportation efficiency of
the anticancer agent without increasing the connecting points to
the antibody.
[0099] In still another aspect of the invention, P in formula (1)
is polyethylene glycol having the number of terminals of 2 to 8,
all the terminals of the polyethylene glycol constituting P are
each connected to Z.sup.1, and w is equal to the number of
terminals of the polyethylene glycol.
[0100] In a preferred embodiment of the aspect, P in formula (1) is
selected from the group consisting of formula (r), formula (s),
formula (t), formula (u) and formula (v), w is 2 in the case where
P is represented by formula (r), w is 3 in the case where P is
represented by formula (s), w is 4 in the case where P is
represented by formula (t), w is 4 in the case where P is
represented by formula (u), and w is 8 in the case where P is
represented by formula (v).
##STR00026##
[0101] A preferred range of n in formula (2) and formula (3) of the
invention is from 3 to 2,000, more preferably from 20 to 1,500,
still more preferably from 40 to 1,000, and most preferably from 60
to 500. Further, a preferred range of n in formula (4), formula (5)
and formula (6) is from 3 to 1,000, preferably from 10 to 800, more
preferably from 20 to 500, and most preferably from 30 to 300.
[0102] According to another aspect of the invention, a cyclic
benzylidene acetal linker compound represented by formula (55) is
provided.
##STR00027##
[0103] Each of R.sup.1 and R.sup.6 in formula (55) of the invention
is a hydrogen atom or a hydrocarbon group, a number of carbon atoms
of the hydrocarbon group is preferably 10 or less and specific
examples of the hydrocarbon group include a methyl group, an ethyl
group, a propyl group, an isopropyl group, a tert-butyl group, a
phenyl group and a benzyl group. A preferred embodiment of R.sup.1
is a hydrogen atom or a methyl group, and a hydrogen atom is more
preferred.
[0104] The benzene ring in formula (55) of the invention may have a
plurality of substituents. By appropriately selecting the kind, the
position and the degree of electron-donating property and
electron-withdrawing property of the substituents on the benzene
ring, it is possible to adjust the degrees of electron density and
steric hindrance around the acetal group which affects the
hydrolysis rate of the cyclic acetal linker. This makes it possible
to impart a desired hydrolysis rate to the cyclic acetal
linker.
[0105] In the specification, the substituent(s) on the benzene ring
in formula (55) is described using the "substituent constant
(.sigma.)" which means the substituent constant in the Hammett's
rule which quantifies the effect of the substituent on the reaction
rate or equilibrium of benzene derivative. However, as is known,
the Hammett's rule is applied only to a para-substituted or
meta-substituted benzene derivative and cannot be applied to an
ortho-substituted benzene derivative which is affected by steric
hindrance. Therefore, in the case of ortho-substituted benzene
derivative, the substituent constant means the substituent constant
in the Taft's equation which extends the Hammett's rule described
above.
[0106] As is known, since the reaction constant (.rho.) of
para-substituted or meta-substituted benzene derivative in the
Hammett's rule and the reaction constant (.rho.*) of
ortho-substituted benzene derivative in the Taft's equation are
approximately equal, it is defined in the specification that .rho.
and .rho.* are the same. Since the substituent constant (.sigma.*)
in the ortho position in the Taft's equation is similar to the
substituent constant in the para position as described, for
example, in "Charton, M. Can. J. Chem. 1960, 38, 2493-2499", to the
substituent constant in the ortho position in the specification is
applied a corresponding substituent constant in the para
position.
[0107] The substituent constant (.sigma.) in the para position or
the meta position is described in "Hansch, C.; Leo. A.; Taft, R. W.
Chem. Rev. 1991, 91, 165-195", and with respect to a substituent in
which the substituent constant (.sigma.) is unknown the constant
can be measured and determined by the method described in "Hammett,
L. P. Chem. Rev. 1935, 17(1), 125-136". Moreover, the position
constant (Es) in the Taft's equation is described in "Unger, S. H.;
Hansch, C. Prog. Phys. Org. Chem. 1976, 12, 91-118". However, as to
Es as used in the specification, a hydrogen atom is defined as
"0".
[0108] In formula (55), in the case where a plurality of
substituents are present on the benzene ring, it is defined that
additivity is established for the substituent constant (.sigma.)
and the position constant (Es) thereof, and the sum of .sigma. is
represented by ".SIGMA..sigma." and the sum of Es is represented by
".SIGMA.Es".
[0109] Z.sup.1 is connected to the benzene ring of the cyclic
benzylidene acetal and X.sup.3--Z.sup.1 is also a substituent of
the benzene ring. The substituent constant of X.sup.3--Z.sup.1 can
be determined by separately measuring the combination of X.sup.3
and Z.sup.1, but, since the substituent constant of
X.sup.3--Z.sup.1 is substantially affected largely by the structure
in the vicinity of the connecting portion to the benzene ring, the
effect of the other portions is so small as to be ignored.
Therefore, it is possible to use a known substituent constant of a
structure similar to the structure in the vicinity of the
connecting portion to the benzene ring in place of separately
measuring the substituent constant as to X.sup.3--Z.sup.1.
[0110] It is defined that the substituent constant of
X.sup.3--Z.sup.1 in the specification can be substituted with a
substituent constant of a structure in which atom(s) connected to
the third atom counted from the atom connected to the benzene atom
of the backbone atoms of the main chain of X.sup.3--Z.sup.1,
excepting the second atom are substituted with hydrogen atom(s).
However, in the case where, when the atom is substituted with a
hydrogen atom, a carboxy group is formed, it is defined that the
substituent constant of X.sup.3--Z.sup.1 can be substituted with a
substituent constant of a structure in which the atom is
substituted with a methyl group in place of a hydrogen atom.
Moreover, in the case where the backbone atoms of the main chain of
X.sup.3--Z.sup.1 is 4 atoms or less, a known substitution constant
described in the references described above is used or a value
obtained by measuring according to the method described in the
references described above can be used.
[0111] Specific examples of the structure of the connecting portion
to the benzene ring in X.sup.3--Z.sup.1 and the structure for the
substitution are shown below. In the case of (r1) shown below,
wherein the connecting portion to the benzene ring in
X.sup.3--Z.sup.1 is an ether bond, a substituent constant of (r2)
shown below is applied. In the cases of (r3) and (r5) shown below,
wherein the connecting portion to the benzene ring in
X.sup.3--Z.sup.1 is an amide bond, substituent constants of (r4)
and (r6) shown below are applied, respectively. In the case of (r7)
shown below, wherein the connecting portion to the benzene ring in
X.sup.3--Z.sup.1 is a urethane bond, a substituent constant of (r8)
shown below is applied.
TABLE-US-00002 Structure of Connecting Portion to Benzene Ring
Structure for Substitution (r1) ##STR00028## (r2) ##STR00029## (r3)
##STR00030## (r4) ##STR00031## (r5) ##STR00032## (r6) ##STR00033##
(r7) ##STR00034## (r8) ##STR00035##
[0112] The substituent which can be used in the aspect is a
substituent which does not inhibit the acetalization reaction and
the terminal functional group conversion reaction in the synthesis
process of the cyclic benzylidene acetal linker compound, and in a
preferred embodiment of the invention it is a substituent which
does not inhibit the coupling reaction of the linker compound with
the hydrophilic polymer intermediate, the terminal functional group
conversion reaction of the hydrophilic polymer derivative obtained
and the bond-forming reaction between the hydrophilic polymer
derivative and the drug or the like, in addition to the reactions
described above.
[0113] The substituent may be any of electron-withdrawing
substituent and electron-donating substituent as far as it
satisfies the conditions described above, and the substituents may
be used individually or in combination. The electron-withdrawing
substituent includes an acyl group having from 2 to 5 carbon atoms,
an alkoxycarbonyl group having from 2 to 5 carbon atoms, a
carbamoyl group having from 2 to 5 carbon atoms, an acyloxy group
having from 2 to 5 carbon atoms, an acylamino group having from 2
to 5 carbon atoms, an alkoxycarbonylamino group having from 2 to 5
carbon atoms, a fluorine atom, a chlorine atom, a bromine atom, an
iodine atom, an alkylsulfanyl group having from 1 to 4 carbon
atoms, an alkylsulfonyl group having from 1 to 4 carbon atoms, an
arylsulfonyl group having from 6 to 10 carbon atoms, a nitro group,
a trifluoromethyl group and a cyano group, and preferred examples
thereof include an acetyl group, a methoxycarbonyl group, a
methylcarbamoyl group, an acetoxy group, an acetamide group, a
methoxycarbonylamino group, a fluorine atom, a chlorine atom, a
bromine atom, an iodine atom, a methylsulfanyl group, a
phenylsulfonyl group, a nitro group, a trifluoromethyl group and a
cyano group. The electron-donating substituent includes an alkyl
group having from 1 to 4 carbon atoms, and preferred examples
thereof include a methyl group, an ethyl group, a propyl group, an
isopropyl group and a tert-butyl group. The substituent which is an
electron-withdrawing group in the meta-position and an
electron-donating group in the para-position and ortho-position
includes an alkoxy group having from 1 to 4 carbon atoms, an aryl
group having from 6 to 10 carbon atom and an aryloxy group having
from 6 to 10 carbon atoms, and preferred examples thereof include a
methoxy group, an ethoxy group, a propoxy group, an isopropoxy
group, a tert-butoxy group, a phenyl group and a phenoxy group.
[0114] As to the hydrolysis rate of the cyclic benzylidene acetal
linker compound of the invention, hydrolysis half-life (t.sub.1/2)
in a buffer at pH 5.5 and 37.degree. C. is preferably in the range
from 1 hour to 6 months, more preferably in the range from 1 hour
to 1 month, and still more preferably in the range from 1 hour to
24 hours.
[0115] In the case where formula (55) includes a 1,3-dioxolane
structure and R.sup.2 and R.sup.5 are hydrogen atoms, a preferred
range of sum (.SIGMA..sigma.) of substituent constants satisfies
-0.30.ltoreq..SIGMA..sigma..ltoreq.0.21 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.24 hours,
-0.30.ltoreq..SIGMA..sigma..ltoreq.0.76 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.1 month and
-0.30.ltoreq..SIGMA..sigma..ltoreq.1.05 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months.
[0116] In the case where formula (55) includes a 1,3-dioxolane
structure and at least one of R.sup.2 and R.sup.5 is a substituent
other than a hydrogen atom, the range of .SIGMA..sigma. satisfies
-1.71.ltoreq..SIGMA..sigma..ltoreq.0.04 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.24 hours,
-1.71.ltoreq..SIGMA..sigma..ltoreq.0.59 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.1 month and
-1.71.ltoreq..SIGMA..sigma..ltoreq.0.88 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months.
[0117] In the case where formula (55) includes a 1,3-dioxolane
structure and R.sup.2 and R.sup.5 are hydrogen atoms, for example,
a preferred embodiment which satisfies
-0.30.ltoreq..SIGMA..sigma..ltoreq.0.21 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.24 hours is described below. However,
the substituents shown herein means R.sup.3, R.sup.4 and
X.sup.3--Z.sup.1 and the structure used in place of
X.sup.3--Z.sup.1 according to the definition described above. In
the preferred embodiment, one of the meta-positions in formula (55)
is a methoxy group, an ethoxy group or an acetamide group, and more
preferably an ethoxy group or an acetamide group. In another
preferred embodiment, the para-position in formula (55) is a
methoxy group or an ethoxy group and one of the meta-positions is a
substituent selected from the group consisting of a fluorine atom,
a chlorine atom, a bromine atom and an iodine atom, and more
preferably the para-position is an ethoxy group and one of the
meta-positions is a fluorine atom or a chlorine atom. In still
another preferred embodiment, one of the para-position and the
meta-position in formula (55) is a methoxy group, an ethoxy group
or an acetamide group, and more preferably a methoxy group or an
ethoxy group.
[0118] Further, in the case where formula (55) includes a
1,3-dioxolane structure and at least one of R.sup.2 and R.sup.5 is
a substituent other than a hydrogen atom, for example, a preferred
embodiment which satisfies -1.71.ltoreq..SIGMA..sigma..ltoreq.0.04
at the time of 1 hour.ltoreq.t.sub.1/2.ltoreq.24 hours is described
below. However, the substituents shown herein means R.sup.3,
R.sup.4 and X.sup.3--Z.sup.1 and the structure used in place of
X.sup.3--Z.sup.1 according to the definition described above. In
the case where one of R.sup.2 and R.sup.5 in formula (55) is a
fluorine atom, a methyl group or an ethyl group and the other is a
hydrogen atom, the para-position is preferably an ethoxy group or
an acetamide group, and more preferably an ethoxy group. In the
case where one of R.sup.2 and R.sup.5 in formula (55) is a methoxy
group and the other is a hydrogen atom, the para-position is
preferably a substituent selected from the group consisting of a
methoxymethyl group and an acetamide group, and more preferably an
acetamide group.
[0119] In the case where formula (55) includes a 1,3-dioxane
structure and R.sup.2 and R.sup.5 are hydrogen atoms, a preferred
range of sum (.SIGMA..sigma.) of substituent constants satisfies
-0.19.ltoreq..SIGMA..sigma..ltoreq.0.10 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.24 hours,
-0.19.ltoreq..SIGMA..sigma..ltoreq.0.41 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.1 month and
-0.19.ltoreq..SIGMA..sigma..ltoreq.0.57 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months.
[0120] Further, in the case where formula (55) includes a
1,3-dioxane structure and at least one of R.sup.2 and R.sup.5 is a
substituent other than a hydrogen atom, the range of .SIGMA..sigma.
satisfies -0.98.ltoreq..SIGMA..sigma..ltoreq.0.00 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.24 hours,
-0.98.ltoreq..SIGMA..sigma..ltoreq.0.31 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.1 month and
-0.98.ltoreq..SIGMA..sigma..ltoreq.0.48 at the time of 1
hour.ltoreq.t.sub.1/2.ltoreq.6 months.
[0121] X.sup.3 and X.sup.4 in formula (55) are each independently a
chemically reactive functional group, and although it is not
intended to limit the application of the linker compound, in a
preferred embodiment of the invention, the hydrophilic polymer
derivative having a cyclic benzylidene acetal linker of formula (1)
can be synthesized by a coupling reaction between X.sup.3 and a
chemically reactive functional group of a hydrophilic polymer
intermediate.
[0122] Preferred examples of X.sup.3 and X.sup.4 in formula (55)
include an active ester group, an active carbonate group, an
aldehyde group, an isocyanate group, an isothiocyanate group, an
epoxy group, a maleimide group, a vinyl sulfone group, an acryl
group, a sulfonyloxy group, a carboxy group, a thiol group, a
dithiopyridyl group, an .alpha.-haloacetyl group, an alkynyl group,
an allyl group, a vinyl group, an amino group, an oxyamino group, a
hydrazide group, an azide group and a hydroxy group. According to a
more specific embodiment, the functional group capable of forming a
covalent bond upon a reaction with an amino group of the reaction
partner is an active ester group, an active carbonate group, an
aldehyde group, an isocyanate group, an isothiocyanate group, an
epoxy group, a maleimide group, a vinyl sulfone group, an acryl
group, a sulfonyloxy group or a carboxy group; the functional group
capable of forming a covalent bond upon a reaction with a thiol
group of the reaction partner is an active ester group, an active
carbonate group, an aldehyde group, an isocyanate group, an
isothiocyanate group, an epoxy group, a maleimide group, a vinyl
sulfone group, an acryl group, a sulfonyloxy group, a carboxy
group, a thiol group, a dithiopyridyl group, an .alpha.-haloacetyl
group, an alkynyl group, an allyl group or a vinyl group; the
functional group capable of forming a covalent bond upon a reaction
with an aldehyde group or a carboxy group of the reaction partner
is a thiol group, an amino group, an oxyamino group or a hydrazide
group; the functional group capable of forming a covalent bond upon
a reaction with an alkynyl group of the reaction partner is a thiol
group or an azide group; the functional group capable of forming a
covalent bond upon a reaction with an azide group of the reaction
partner is an alkynyl group; and the functional group capable of
forming a covalent bond upon a reaction with a halogenated alkyl
group, an alkylsulfonate or an arylsulfonate of the reaction
partner is a hydroxy group, a thiol group or an amino group.
[0123] In a preferred embodiment of the aspect, X.sup.3 and X.sup.4
are each a group represented by group (I), group (II), group (III),
group (IV), group (V) or group (VI).
Group (I): Functional group capable of forming a covalent bond upon
a reaction with an amino group of the reaction partner
[0124] (a), (b), (c), (d), (e) and (f) shown below:
Group (II): Functional group capable of forming a covalent bond
upon a reaction with a thiol group of the reaction partner
[0125] (a), (b), (c), (d), (e), (f), (g), (h), (i) and (j) shown
below:
Group (III): Functional group capable of forming a covalent bond
upon a reaction with an aldehyde group or a carboxy group of the
reaction partner
[0126] (g), (k), (l) and (m) shown below:
Group (IV): Functional group capable of forming a covalent bond
upon a reaction with an alkynyl group of the reaction partner
[0127] (g), (k), (l), (m) and (n) shown below
Group (V): Functional group capable of forming a covalent bond upon
a reaction with an azide group of the reaction partner
[0128] (j) shown below:
Group (VI): Functional group capable of forming a covalent bond
upon a reaction with a halogenated alkyl group, an alkylsulfonate
or an arylsulfonate of the reaction partner
[0129] (o), (g) and (k) shown below:
##STR00036##
[0130] In the formulae above, R.sup.7 is a hydrogen atom or a sulfo
group, specific examples of the sulfo group include sodium
sulfonate and potassium sulfonate, and R.sup.7 is preferably a
hydrogen atom. R.sup.8 and R.sup.11 are each a hydrogen atom or a
hydrocarbon group having from 1 to 5 carbon atoms, and specific
examples of the hydrocarbon group include a methyl group, an ethyl
group, a propyl group, an isopropyl group, a butyl group, a
tert-butyl group and a pentyl group. R.sup.9 is a hydrocarbon group
having from 1 to 10 carbon atoms which may contain a halogen atom,
specific examples of the hydrocarbon group include a methyl group,
an ethyl group, a propyl group, an isopropyl group, a butyl group,
a tert-butyl group, a pentyl group, an isopentyl group, a hexyl
group, a benzyl group, a 4-methylphenyl group, a trifluoromethyl
group, a 2,2,2-trifluoroethyl group, a 4-(trifluoromethoxy)phenyl
group, a vinyl group, a chloroethyl group, a bromoethyl group and
an iodoethyl group, and R.sup.9 is preferably a methyl group, a
vinyl group, a 4-methylphenyl group or a 2,2,2-trifluoroethyl
group. R.sup.10 is a halogen atom selected from a chlorine atom, a
bromine atom and an iodine atom.
[0131] X.sup.3 and X.sup.4 may be the same or different from each
other. As to preferred examples of a combination of X.sup.3 and
X.sup.4 which are different from each other, when X.sup.3 is an
active ester group or an active carbonate group, X.sup.4 is a group
selected from a maleimide group, a vinyl sulfone group, an
.alpha.-haloacetyl group, an alkynyl group and an azide group; when
X.sup.3 is an aldehyde group, X.sup.4 is a group selected from a
maleimide group, a vinyl sulfone group, an alkynyl group and an
azide group; when X.sup.3 is a maleimide group, a vinyl sulfone
group or an .alpha.-haloacetyl group, X.sup.4 is a group selected
from an active ester group, an active carbonate group, an alkynyl
group and an azide group; when X.sup.3 is an alkynyl group or an
azide group, X.sup.4 is a group selected from a maleimide group, a
vinyl sulfone group, an .alpha.-haloacetyl group, an active ester
group, an active carbonate group, an amino group, an oxyamino group
and a hydroxy group; when X.sup.3 is an amino group or an oxyamino
group, X.sup.4 is an alkynyl group, an azide group, a thiol group,
a hydroxy group or a carboxy group; and when X.sup.3 is a thiol
group or a hydroxy group, X.sup.4 is a group selected from an amino
group, an oxyamino group, an azide group and a carboxy group. More
preferably, when X.sup.3 is an active ester or an active carbonate
group, X.sup.4 is a group selected from a maleimide group, an
.alpha.-haloacetyl group, an alkynyl group and an azide group; when
X.sup.3 is an aldehyde group, X.sup.4 is a group selected from a
maleimide group, an .alpha.-haloacetyl group, an alkynyl group and
an azide group; when X.sup.3 is a maleimide group or an
.alpha.-haloacetyl group, X.sup.4 is a group selected from an
active ester group, an active carbonate group, an alkynyl group and
an azide group; when X.sup.3 is an alkynyl group or an azide group,
X.sup.4 is a group selected from a maleimide group, an
.alpha.-haloacetyl group, an active ester group, an active
carbonate group, an amino group, an oxyamino group and a hydroxy
group; when X.sup.3 is an amino group or an oxyamino group, X.sup.4
is an alkynyl group, an azide group, a hydroxy group or a thiol
group; and when X.sup.3 is a thiol group or a hydroxy group,
X.sup.4 is a group selected from an amino group, an oxyamino group
and an azide group.
[0132] Z.sup.1 in formula (55) of the aspect is a divalent spacer
between the benzene ring of the cyclic benzylidene acetal group and
the functional group X.sup.3, and Z.sup.2 is a divalent spacer
between the functional group X.sup.4 and the cyclic benzylidene
acetal group. These are composed of covalent bonds, are not
particularly limited as long as they are more stable to acid
hydrolysis than the cyclic benzylidene acetal group, and are
preferably an ether bond, an ester bond, a carbonate bond, a
urethane bond, an amide bond, a secondary amino group, an alkylene
group containing any of these bonds and group, a single bond or an
alkylene group. The number of carbon atoms of the alkylene group is
preferably from 1 to 24. By way of illustration and without
limitation, preferred examples of the alkylene group include
structures such as (z1). Preferred examples of the alkylene group
having an ether bond include structures such as (z2) or (z3).
Preferred examples of the alkylene group having an ester bond
include structures such as (z4). Preferred examples of the alkylene
group having a carbonate bond include structures such as (z5).
Preferred examples of the alkylene group having a urethane bond
include structures such as (z6). Preferred examples of the alkylene
group having an amide bond include structures such as (z7).
Preferred examples of the alkylene group having a secondary amino
group include structures such as (z8). In a preferred embodiment, p
and q are each independently an integer of 1 to 12. However, in the
case where at least one of Z.sup.1 and Z.sup.2 is an ether bond, an
ester bond, a carbonate bond, a urethane bond, an amide bond, a
secondary amino group or an alkylene group containing any of these
bonds and group and a plurality of identical structural units are
connected, a number of the structural units described above is 2 or
less.
##STR00037##
[0133] The hydrophilic polymer derivative having a cyclic
benzylidene acetal linker of the invention can be synthesized by
performing a coupling reaction between a cyclic benzylidene acetal
linker compound having a substituent and a hydrophilic polymer
intermediate. The bond generated by the coupling reaction is
determined by a combination of the functional groups used in the
reaction, and is the ether bond, the ester bond, the carbonate
bond, the urethane bond, the amide bond, the secondary amino group,
the alkylene group containing any of these bonds and group, the
single bond or the alkylene group contained in the divalent spacer
Z.sup.1 described above. In the hydrophilic polymer derivative
synthesized, the terminal functional group is chemically converted,
if desired. As the reaction used for the functional group
conversion, a conventionally known method can be used, but it is
necessary to appropriately select conditions which do not decompose
the cyclic benzylidene acetal group of formula (1) and the bonds
contained in the divalent spacers Z.sup.1 and Z.sup.2 described
above.
[0134] As a typical example of performing the coupling reaction
between the cyclic benzylidene acetal linker compound and the
hydrophilic polymer intermediate and further the chemical
conversion of the terminal functional group, the steps described
below are exemplified. Polyethylene glycol which is a typical
hydrophilic polymer is described herein as an example.
(A) Synthesis of Cyclic Benzylidene Acetal Linker Compound
##STR00038##
[0135] wherein R.sup.1 is a hydrogen atom or a hydrocarbon group;
and R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are each independently an
electron-withdrawing or electron-donating substituent or a hydrogen
atom.
##STR00039##
[0136] A carbonyl compound of formula (14) having a hydroxy group
which is a chemically reactive functional group is allowed to react
with a 1,2-diol derivative of formula (15) having a phthalimide
group in which an amino group is protected with a phthaloyl group
in an aprotic solvent, for example, toluene, benzene, xylene,
acetonitrile, ethyl acetate, diethyl ether, tert-butyl methyl
ether, tetrahydrofuran, chloroform, dichloromethane, dimethyl
sulfoxide, dimethylformamide or dimethylacetamide or with no
solvent in the presence of an acid catalyst to obtain a compound of
the following formula (16) having a cyclic benzylidene acetal
group. The resulting compound may be purified by extraction,
recrystallization, adsorbent treatment, column chromatography or
the like. In place of the carbonyl compound, it is possible to use
a corresponding acetal derivative of a lower alcohol. The lower
alcohol is preferably an alcohol having from 1 to 5 carbon atoms,
and more preferably methanol or ethanol. The acid catalyst may be
either an organic acid or an inorganic acid and is not particularly
limited, and specific examples thereof include p-toluenesulfonic
acid, pyridinium p-toluenesulfonate, methanesulfonic acid,
10-camphorsulfonic acid, hydrogen chloride, iodine, ammonium
chloride, oxalic acid, boron trifluoride-diethyl ether complex and
the like.
##STR00040##
[0137] The "protective group" as referred to herein is a component
which prevents or blocks a reaction of a specific chemically
reactive functional group in a molecule under certain reaction
conditions. The protective group varies depending on the kind of
the chemically reactive functional group to be protected, the
conditions to be used and the presence of the other functional
group or protective group in the molecule. Specific examples of the
protective group can be found in many general books and are
described, for example, in "Wuts, P. G. M.; Greene, T. W.,
Protective Groups in Organic Synthesis, 4th ed.;
Wiley-Interscience: New York, 2007". Moreover, the functional group
protected by the protective group can be reproduce the original
functional group by deprotection using reaction conditions suitable
for each of the protective groups, that is, causing a chemical
reaction. Therefore, in the specification, a functional group which
is protected by a protective group and is capable of being
deprotected by various reactions is included in the "chemically
reactive functional group". The typical deprotection conditions of
the protective group are described in the literature described
above.
[0138] As the chemically reactive functional group in the compound
of formula (14), a functional group other than the hydroxy group
can also be used. Specific examples thereof include a hydroxyalkyl
group, an amino group, an aminoalkyl group, a carboxy group and a
carboxyalkyl group. Also, the functional group described above may
be protected by a protective group which is stable in the acidic
conditions of the acetalization reaction and can be deprotected
under reaction conditions other than catalytic reduction by which
the cyclic benzylidene acetal group is decomposed. As to preferred
combinations of the functional group to be protected and the
protective group, when the functional group to be protected is a
hydroxy group or a hydroxyalkyl group, for example, a silyl
protective group and an acyl protective group are exemplified, and
specific examples thereof include a tert-butyldiphenylsilyl group,
a tert-butyldimethylsilyl group, a triisopropylsilyl group, an
acetyl group and a pivaloyl group. When the functional group to be
protected is an amino group or an aminoalkyl group, for example, an
acyl protective group and a carbamate protective group are
exemplified, and specific examples thereof include a
trifluoroacetyl group, a 9-fluorenylmethyloxycarbonyl group and a
2-(trimethylsilyl)ethyloxycarbonyl group. When the functional group
to be protected is a carboxy group or a carboxyalkyl group, for
example, an alkyl ester protective group and a silyl ester
protective group are exemplified, and specific examples thereof
include a methyl group, a 9-fluorenylmethyl group and a
tert-butyldimethylsilyl group. The kinds and the typical
deprotection conditions of the specific protective groups are
described in the literature described above, and the reaction
conditions suitable for each of the protective groups are selected
and the deprotection can be performed before the reaction with the
hydrophilic polymer intermediate.
[0139] Moreover, as the chemically reactive functional group
excepting the 1,2-diol moiety in the compound of formula (15), a
functional group other than the phthalimide group can also be used.
In the case where the chemically reactive functional group is a
functional group which is protected by a protective group, it is
necessary that the protective group is stable in the acidic
conditions of the acetalization reaction and can be deprotected
under reaction conditions other than catalytic reduction by which
the benzylidene acetal group is decomposed. As to preferred
combinations of the functional group to be protected and the
protective group, when the functional group to be protected is an
amino group, for example, an acyl protective group and a carbamate
protective group are exemplified, and specific examples thereof
include a trifluoroacetyl group, a 9-fluorenylmethyloxycarbonyl
group and a 2-(trimethylsilyl)ethyloxycarbonyl group. When the
functional group to be protected is a hydroxy group, for example, a
silyl protective group and an acyl protective group are
exemplified, and specific examples thereof include a
tert-butyldiphenylsilyl group, a tert-butyldimethylsilyl group, a
triisopropylsilyl group, an acetyl group and a pivaloyl group. When
the functional group to be protected is a carboxy group, for
example, an alkyl ester protective group and a silyl ester
protective group are exemplified, and specific examples thereof
include a methyl group, a 9-fluorenylmethyl group and a
tert-butyldimethylsilyl group. When the functional group to be
protected is a sulfanyl group, for example, a thioether protective
group, a thiocarbonate protective group and a disulfide protective
group are exemplified, and specific examples thereof include an
S-2,4-dinitrophenyl group, an S-9-fluorenylmethyloxycarbonyl group
and an S-tert-butyldisulfide group. The typical deprotection
conditions of the protective group are described in the literature
described above, and the reaction conditions suitable for each of
the protective groups are selected. However, in the case where the
chemically reactive functional group is a functional group which
does not inhibit the acetalization reaction even when it is not
protected by a protective group, it is not necessary to use a
protective group.
(B) Synthesis of Polyethylene Glycol Intermediate
[0140] Ethylene oxide is polymerized in an amount of 3 to 2,000
molar equivalents to methanol, which is an initiator, in toluene or
with no solvent under alkaline conditions, for example, metallic
sodium, metallic potassium, sodium hydride or potassium hydride to
obtain polyethylene glycol of formula (17). The initiator is
preferably an alcohol having a hydrocarbon group having from 1 to
24 carbon atoms, and specifically includes methanol, ethanol,
propanol, isopropanol butanol, tert-butanol, phenol and benzyl
alcohol. Since the polyethylene glycol has a hydroxy group which is
a chemically reactive functional group, it can be used as it is in
a coupling reaction with a cyclic benzylidene acetal linker
compound.
CH.sub.3--(OCH.sub.2CH.sub.2).sub.n--OH (17)
[0141] The polyethylene glycol of formula (17) is allowed to react
with methanesulfonyl chloride in an aprotic solvent, for example,
toluene, benzene, xylene, acetonitrile, ethyl acetate, diethyl
ether, tert-butyl methyl ether, tetrahydrofuran, chloroform,
dichloromethane, dimethyl sulfoxide, dimethylformamide or
dimethylacetamide or with no solvent in the presence of an organic
base, for example, triethylamine, N-methylmorpholine, pyridine or
4-dimethylaminopyridine or an inorganic base, for example, sodium
carbonate, sodium hydrogen carbonate, sodium acetate or potassium
carbonate to obtain a polyethylene glycol intermediate of formula
(18). The organic base and inorganic base may not be used. The use
ratio of the organic base or the inorganic base is not particularly
limited, and is preferably equimolar or more to the hydroxyl group
of the polyethylene glycol of formula (17). Also, it is possible to
use the organic base as a solvent. The compound obtained may be
purified by a purification means, for example, extraction,
recrystallization, adsorbent treatment, reprecipitation, column
chromatography or supercritical extraction.
##STR00041##
[0142] As the chemically reactive functional group in the
polyethylene glycol intermediate of formula (18), other functional
groups can be also used. Preferred examples of the chemically
reactive functional group are functional groups wherein the bond
generated by the coupling reaction of the polyethylene glycol
intermediate with the cyclic benzylidene acetal linker compound
described above becomes the ether bond, the ester bond, the
carbonate bond, the urethane bond, the amide bond, the secondary
amino group, the alkylene group containing any of these bonds and
group, the single bond or the alkylene group contained in the
divalent spacer Z.sup.1 of formula (1), and specifically include,
for example, a halogen atom, an active ester, an active carbonate,
an aldehyde group, an amino group, a hydroxy group and a carboxy
group.
(C) Coupling Reaction Between Cyclic Benzylidene Acetal Linker
Compound and Polyethylene Glycol Intermediate
[0143] The benzylidene acetal linker compound of formula (16) and
the polyethylene glycol intermediate of formula (18) are subjected
to a coupling reaction in an aprotic solvent, for example, toluene,
benzene, xylene, acetonitrile, ethyl acetate, diethyl ether,
tert-butyl methyl ether, tetrahydrofuran, chloroform,
dichloromethane, dimethyl sulfoxide, dimethylformamide or
dimethylacetamide or with no solvent in the presence of an organic
base, for example, triethylamine, N-methylmorpholine, potassium
tert-butoxide or sodium hexamethyldisilazane or an inorganic base,
for example, potassium carbonate, potassium hydroxide or sodium
hydride to obtain a compound of formula (19). The use ratio of the
organic base or the inorganic base is not particularly limited, and
is preferably equimolar or more to the chemically reactive
functional group of the polyethylene glycol intermediate of formula
(18). Also, it is possible to use the organic base as a solvent.
The compound obtained may be purified by the purification means
described above.
##STR00042##
[0144] The chemically reactive functional group of the cyclic
benzylidene acetal linker compound may be subjected to functional
group conversion before the coupling reaction with the polyethylene
glycol intermediate. The reaction conditions for the coupling
reaction are determined depending on the combination of the
chemically reactive functional group of the cyclic benzylidene
acetal linker compound and the chemically reactive functional group
of the polyethylene glycol intermediate and a conventionally known
method can be used. However, it is necessary to appropriately
select conditions which do not decompose the bonds contained in the
cyclic benzylidene acetal group and the divalent spacers Z.sup.1
and Z.sup.2 described above of formula (1)
(D) Terminal Functional Group Conversion of the Polyethylene Glycol
Derivative Having Cyclic Benzylidene Acetal Linker
[0145] The compound of formula (19) is treated by using a basic
organic compound, for example, ethylenediamine, methyl hydrazine or
methylamine or a basic inorganic compound, for example, hydrazine,
hydroxylamine or sodium hydroxide in a protic solvent, for example,
water, methanol or ethanol, in an aprotic solvent, for example,
acetonitrile, tetrahydrofuran, dimethyl sulfoxide,
dimethylformamide or dimethylacetamide or with no solvent to obtain
a compound of formula (20) in which the phthalimide group is
deprotected and converted into an amino group. The use ratio of the
basic compound is not particularly limited, and is preferably
equimolar or more to the chemically reactive functional group of
the compound of formula (19). Also, it is possible to use the basic
compound as a solvent. The compound obtained may be purified by the
purification means described above.
##STR00043##
[0146] Furthermore, the compound of formula (20) is allowed to
react with N-succinimidyl 3-maleimidopropionate in an aprotic
solvent, for example, toluene, benzene, xylene, acetonitrile, ethyl
acetate, diethyl ether, tert-butyl methyl ether, tetrahydrofuran,
chloroform, dichloromethane, dimethyl sulfoxide, dimethylformamide
or dimethylacetamide or with no solvent in the presence of an
organic base, for example, triethylamine, N-methylmorpholine,
pyridine or 4-dimethylaminopyridine or an inorganic base, for
example, sodium carbonate, sodium hydrogen carbonate, sodium
acetate or potassium carbonate to obtain a compound of formula (21)
in which a maleimide group is introduced into the terminal. The
organic base and inorganic base may not be used. The use ratio of
the organic base or the inorganic base is not particularly limited,
and is preferably equimolar or more to the chemically reactive
functional group of the compound of formula (20). Also, it is
possible to use the organic base as a solvent. The compound
obtained may be purified by the purification means described
above.
##STR00044##
EXAMPLES
[0147] The invention will be described more specifically with
reference to the examples, but the invention should not be
construed as being limited thereto.
[0148] In .sup.1H-NMR analysis, JNM-ECP400 or JNM-ECA600 produced
by JEOL DATUM Ltd. was used. For the measurement, a tube of 5 mm
.phi. was used, and tetramethylsilane (TMS) was used as an internal
standard substance in the case where a deuterated solvent was
CDCl.sub.3, CD.sub.3CN or CD.sub.3OD, or HDO was used as a standard
in the case of D.sub.2O.
[0149] In gel permeation chromatography (GPC) analysis, there were
used SHODEX GPC SYSTEM-11 as a GPC system, SHODEX RIX8 as a
differential refractometer which is a detector, and three columns,
i.e., SHODEX KF801L, KF803L and KF804L (.phi. 8 mm.times.300 mm)
connected in series as GPC columns, and the temperature of the
column oven was set to 40.degree. C. The measurement was performed
using tetrahydrofuran as an eluent, at the flow rate of 1 ml/min,
at the sample concentration of 0.1% by weight, and in the injection
volume of 0.1 ml. The calibration curves prepared by using ethylene
glycol, diethylene glycol and triethylene glycol produced by Kanto
Chemical Co., Ltd. and Polymer Standards for GPC of polyethylene
glycol or polyethylene oxide having a molecular weight of 600 to
70,000 produced by Polymer Laboratory Co., Ltd. For analysis of
data, BORWIN GPC calculation program was used. Mn represents a
number average molecular weight, Mw represents a weight average
molecular weight, and a molecular weight distribution is indicated
as a calculated value of Mw/Mn.
[0150] A deuterated water buffer of MES (2-morpholinoethanesulfonic
acid) having pD of 5.5 and a deuterated water buffer of HEPES
(2-[4-(Hydroxyethyl)-1-piperazinyl]ethanesulfonic acid) having pD
of 7.4 for use in hydrolysis test were prepared by adding a 0.1M
sodium hydroxide deuterated water solution to a 0.1M MES deuterated
water solution and a 0.1M HEPES deuterated water solution,
respectively, based on the relational equation shown below
described in "Glasoe. P. K.; Long, F. A., J. Phys. Chem. 1960, 64,
188-190".
pD=Measured value by pH meter+0.40
[0151] A hydrolysis ratio was evaluated by .sup.1H-NMR and
calculated according to the calculation equation shown below by
taking an integrated value of the hydrogen of the acetal group and
an integral value of the hydrogen of the aldehyde group to be
formed by hydrolysis as I.sup.1 and I.sup.2, respectively.
Hydrolysis ratio (%)=[I.sup.2/(I.sup.1+I.sup.2)].times.100
Example 1
[0152] Into a 200 mL three-necked flask equipped with a
thermometer, a nitrogen inlet tube, a stirrer, a Dean-stark tube
and a condenser tube were charged 1,2,6-hexanetriol (30.0 g, 0.224
mol), acetone dimethyl acetal (25.6 g, 0.246 mol) and
p-toluenesulfonic acid monohydrate (0.426 g, 2.24 mmol), and the
reaction was performed a 80.degree. C. for 3 hours while distilling
off methanol. Triethylamine (0.453 g, 4.48 mmol) was added thereto
and the mixture was stirred for a while, diluted with ethyl
acetate, and washed with an aqueous 20% by weight sodium chloride
solution. The organic layer was dried over anhydrous sodium
sulfate, and after filtration, the solvent was distilled off under
a reduced pressure. The residue was purified by silica gel
chromatography to obtain a compound of formula (22).
[0153] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.35 (3H, s, --CH.sub.3), 1.41 (3H, s, --CH.sub.3),
1.49-1.67 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 2.07 (1H, brs,
--OH), 3.51 (1H, t, --OCH.sub.2CH<), 3.64 (2H, t, --CH.sub.2OH),
4.04 (1H, dd, --OCH.sub.2CH<), 4.07-4.10 (1H, m,
--OCH.sub.2CH<)
##STR00045##
Example 2
[0154] Into a 500 mL four-necked flask equipped with a thermometer,
a nitrogen inlet tube, a stirrer and a condenser tube were charged
the compound of formula (22) (20.0 g, 0.115 mol), triethylamine
(23.3 g, 0.230 mol) and toluene (200 g) and the mixture was cooled
to 10.degree. C. or less. While continuing the cooling,
methanesulfonyl chloride (19.8 g, 0.173 mol) prepared in a dropping
funnel was gradually added dropwise thereto. After the completion
of the dropwise addition, the reaction was performed at 20.degree.
C. for 2 hours. Ethanol (7.97 g, 0.173 mol) was added and the
mixture was stirred for a while and filtered. The organic layer was
washed with ion-exchanged water, dried over anhydrous sodium
sulfate, and after filtration, the solvent was distilled off under
a reduced pressure to obtain a compound of formula (23).
[0155] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.35 (3H, s, --CH.sub.3), 1.40 (3H, s, --CH.sub.3),
1.44-1.83 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 3.01 (3H, s,
--OSO.sub.2CH.sub.3), 3.51 (1H, t, --OCH.sub.2CH<), 4.03-4.11
(2H, m, --OCH.sub.2CH<, --OCH.sub.2CH<), 4.24 (2H, t,
--CH.sub.2OSO.sub.2CH.sub.3)
##STR00046##
Example 3
[0156] Into a 500 mL four-necked flask equipped with a thermometer,
a nitrogen inlet tube, a stirrer and a condenser tube were charged
the compound of formula (23) (20.0 g, 79.3 mmol), potassium
phthalimide (17.6 g, 95.2 mmol) and dehydrated dimethylformamide
(200 g), and the reaction was performed at 60.degree. C. for 2
hours. The mixture was cooled to 10.degree. C. or less,
ion-exchanged water (400 g) was added thereto and after stirring
for a while, the mixture was extracted with a mixed solution of
ethyl acetate/hexane (60/40 in v/v). The organic layer was washed
with an aqueous 0.2% by weight potassium carbonate solution and
dried over anhydrous sodium sulfate. After filtration, the solvent
was distilled off under a reduced pressure to obtain a compound of
formula (24).
[0157] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.34 (3H, s, --CH.sub.3), 1.39 (3H, s, --CH.sub.3),
1.44-1.75 (61, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 3.50 (1H, t,
--OCH.sub.2CH<), 3.69 (2H, t, --CH.sub.2-phthalimide), 4.01-4.09
(2H, m, --OCH.sub.2CH<, --OCH.sub.2CH<), 7.71-7.85 (41H, m,
-phthalimide)
##STR00047##
Example 4
[0158] Into a 1 L four-necked flask equipped with a thermometer, a
nitrogen inlet tube, a stirrer and a condenser tube were charged
the compound of formula (24) (15.2 g, 50.0 mmol), p-toluenesulfonic
acid monohydrate (951 mg, 5.00 mmol) and methanol (500 mL), and the
reaction was performed at room temperature for 4 hours.
Triethylamine (1.01 g, 10.0 mmol) was added thereto and after
stirring for a while, the solvent was distilled off under a reduced
pressure. The residue was dissolved in chloroform, the solution was
washed with ion-exchanged water, and the organic layer was dried
over anhydrous sodium sulfate. After filtration, the solvent was
distilled off under a reduced pressure to obtain a compound of
formula (25).
[0159] .sup.1H-NMR (CD.sub.3CN, internal standard TMS); .delta.
(ppm): 1.24-1.61 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 2.69
(1H, t, --OH), 2.75 (1H, d, --OH), 3.17-3.21 (1H, m,
--OCH.sub.2CH<), 3.31-3.37 (1H, m, --OCH.sub.2CH<), 3.39-3.43
(11, m, --OCH.sub.2CH<), 3.54 (2H, t, --CH.sub.2-phthalimide),
7.67-7.75 (4H, m, -phthalimide)
##STR00048##
Example 5
[0160] Into a 300 mL three-necked flask equipped with a
thermometer, a nitrogen inlet tube, a stirrer, a Dean-stark tube
and a condenser tube were charged the compound of formula (25)
(3.87 g, 14.7 mmol), 4-hydroxybenzaldehyde (1.20 g, 9.83 mmol),
pyridinium p-toluenesulfonate (247 mg, 0.983 mmol) and toluene (180
g), and the reaction was performed for 4 hours while removing
by-produced water by azeotropic distillation with toluene.
Triethylamine (199 mg, 1.97 mmol) was added thereto and after
stirring for a while, the solvent was distilled off under a reduced
pressure. The residue was dissolved in chloroform, the solution was
washed in order with an aqueous 20% by weight sodium chloride
solution and ion-exchanged water, and the organic layer was dried
over anhydrous sodium sulfate. After filtration, the solvent was
distilled off under a reduced pressure to obtain a compound of
formula (26).
[0161] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.41-1.80 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--),
3.57-4.26 (5H, m, --OCH.sub.2CH<, --CH.sub.2- phthalimide), 5.71
(0.611, s, >CH--), 5.82 (0.4H, s, >CH--), 6.79-6.82 (2H, m,
arom. H), 7.31-7.35 (2H, m, arom. H), 7.70-7.86 (4H, m,
-phthalimide)
##STR00049##
Example 6
[0162] Into a 300 mL four-necked flask equipped with a thermometer,
a nitrogen inlet tube, a stirrer and a condenser tube were charged
dehydrated methanol (12.8 g, 0.400 mol), dehydrated toluene (150 g)
and metal sodium (0.3 g, 13 mmol), and the mixture was stirred at
room temperature until the metal sodium was dissolved while
bubbling nitrogen through the mixture. The solution was charged
into a 5 L autoclave and after the inside of the system was
substituted with nitrogen, temperature was raised to 100.degree. C.
After adding ethylene oxide (1,987 g, 45 mol) at 100 to 130.degree.
C. under a pressure of 1 MPa or less, the reaction was further
continued for 2 hours. After the unreacted ethylene oxide gas was
removed under a reduced pressure, the mixture was cooled to
60.degree. C. and pH was adjusted to 7.5 with an aqueous 85%
phosphoric acid solution to obtain a compound of formula (27).
[0163] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 2.68 (1H, t, OH), 3.38 (3H, s, CH.sub.3O--), 3.49-3.85
(450H, m, --(OCH.sub.2CH.sub.2).sub.n--)
[0164] GPC analysis; number average molecular weight (Mn): 5119,
weight average molecular weight (Mw): 5226, polydispersity (Mw/Mn):
1.021
CH.sub.3--(OCH.sub.2CH.sub.2).sub.n--OH (27) n=about 113
Example 7
[0165] Into a 500 mL three-necked flask equipped with a
thermometer, a nitrogen inlet tube, a stirrer, a Dean-stark tube
and a condenser tube were charged the compound of formula (27) (100
g, 20.0 mmol) and toluene (250 g), and water was removed by
azeotropic distillation with toluene. After cooling to 40.degree.
C., triethylamine (324 g, 32.0 mmol) was charged and
methanesulfonyl chloride (2.75 g, 24.0 mmol) prepared in a dropping
funnel was gradually added dropwise thereto. After the completion
of the dropwise addition, the reaction was performed at 40.degree.
C. for 3 hours. Ethanol (1.11 g, 24.0 mmol) was added thereto and
the mixture was stirred for a while, filtered, and diluted with
ethyl acetate (200 g). Crystallization was performed by adding
hexane (500 g), and after filtration, the crystals were dissolved
in ethyl acetate (500 g). Crystallization was again performed by
adding hexane (500 g), and after filtration, the crystals were
dried under a reduced pressure to obtain a compound of formula
(28).
[0166] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 3.08 (3H, s, --OSO.sub.2CH.sub.3), 3.38 (3H, s,
CH.sub.3O--), 3.52-3.85 (448H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--), 4.37-4.39 (2H, m,
--CH.sub.2OSO.sub.2CH.sub.3)
[0167] GPC analysis; number average molecular weight (Mn): 5197,
weight average molecular weight (Mw): 5306, polydispersity (Mw/Mn):
1.021
##STR00050##
Example 8
[0168] Into a 100 mL three-necked flask equipped with a
thermometer, a nitrogen inlet tube, a stirrer and a condenser tube
were charged the compound of formula (28) (5.00 g, 1.00 mmol), the
compound of formula (26) (551 mg, 1.50 mmol), potassium carbonate
(691 mg, 5.00 mmol) and acetonitrile (25 g), and the reaction was
performed at 80.degree. C. for 4 hours. After distilled off the
solvent under a reduce pressure, the residue was dissolved in ethyl
acetate (100 g) and the solution was filtered. Crystallization was
performed by adding hexane (100 g), and after filtration, the
crystals were dried under a reduced pressure to obtain a compound
of formula (29).
[0169] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.40-1.81 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 3.38
(3H, s, CH.sub.3O--), 3.52-4.25 (455H, m,
--(OCH.sub.2CH.sub.2).sub.n--, --OCH.sub.2CH<,
--CH.sub.2-phthalimide), 5.72 (0.6H, s, >CH--), 5.84 (0.4H, s,
>CH--), 6.89-6.91 (2H, m, arom. H), 7.35-7.39 (2H, m, arom. H),
7.70-7.86 (4H, m, -phthalimide)
[0170] GPC analysis; number average molecular weight (Mn): 5462,
weight average molecular weight (Mw): 5582, polydispersity (Mw/Mn):
1.022
##STR00051##
Example 9
[0171] Into a 50 mL three-necked flask equipped with a thermometer,
a nitrogen inlet tube, a stirrer and a condenser tube were charged
the compound of formula (29) (2.00 g, 0.400 mmol), methanol (7 g)
and ethylene diamine monohydrate (0.781 g, 10.0 mmol), and the
reaction was performed at 40.degree. C. for 4 hours. The mixture
was diluted with an aqueous 20% by weight sodium chloride solution,
extracted with dichloromethane, and the solvent was distilled off
under a reduced pressure. The residue was dissolved in ethyl
acetate (50 g), dried over anhydrous sodium sulfate, filtered, and
crystallized by adding hexane (50 g). After filtration, the
crystals were dried under a reduced pressure to obtain a compound
of formula (30).
[0172] .sup.1H-NMR (CD.sub.3OD, internal standard TMS); .delta.
(ppm): 1.43-1.79 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 2.77
(2H, t, --CH.sub.2--NH.sub.2), 3.36 (3H, s, CH.sub.3O--), 3.50-4.29
(453H, m, --(OCH.sub.2CH.sub.2).sub.n--, --OCH.sub.2CH<), 5.70
(0.6H, s, >CH--), 5.81 (0.4H, s, >CH--), 6.93-6.98 (2H, m,
arom. H), 7.33-7.41 (2H, m, arom. H)
[0173] GPC analysis; number average molecular weight (Mn): 5332,
weight average molecular weight (Mw): 5454, polydispersity (Mw/Mn):
1.023
##STR00052##
Example 10
[0174] Into a 50 mL three-necked flask equipped with a thermometer,
a nitrogen inlet tube, a stirrer and a condenser tube were charged
the compound of formula (30) (0.20 g, 0.040 mmol) and acetonitrile
(10 g), and N-succinimidyl 3-maleimidopropionate (32 mg, 0.048
mmol) was added thereto, and the reaction was performed at
25.degree. C. for 3 hours. After filtration, the solvent was
distilled off under a reduced pressure. The residue was dissolved
in ethyl acetate (25 g), and crystallized by adding hexane (25 g).
After filtration, the crystals were dried under a reduced pressure
to obtain a compound of formula (31).
[0175] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.40-1.81 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 2.44
(2H, t, --CH.sub.2CH.sub.2-maleimide), 3.27-3.37 (2H, m,
--CH.sub.2NHCO--), 3.38 (3H, s, CH.sub.3O--), 3.47-4.25 (455H, m,
--(OCH.sub.2CH.sub.2).sub.n--, --OCH.sub.2CH<,
--CH.sub.2CH.sub.2-maleimide), 5.72 (0.6H, s, >CH--), 5.84
(0.4H, s, >CH--), 6.15 (1H, brs, --NHCO--), 6.70 (2H, s,
-maleimide), 6.89-6.91 (2H, m, arom. H), 7.35-7.39 (2H, m, arom.
H)
[0176] GPC analysis; number average molecular weight (Mn): 5484,
weight average molecular weight (Mw): 5610, polydispersity (Mw/Mn):
1.023
##STR00053##
Example 11
[0177] A compound of formula (32) was obtained in the same manner
as in Examples 1 to 8 using 3-fluoro-4-hydroxybenzaldehyde.
[0178] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.38-1.80 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 3.38
(3H, s, CH.sub.3O--), 3.52-4.23 (455H, m,
--(OCH.sub.2CH.sub.2).sub.n--, --OCH.sub.2CH<,
--CH.sub.2-phthalimide), 5.70 (0.6H, s, >CH--), 5.82 (0.4H, s,
>CH--), 6.95-7.21 (3H, m, arom. H), 7.70-7.86 (4H, m,
-phthalimide)
[0179] GPC analysis; number average molecular weight (Mn): 5485,
weight average molecular weight (Mw): 5606, polydispersity (Mw/Mn):
1.022
##STR00054##
Example 12
[0180] A compound of formula (33) was obtained in the same manner
as in Examples 1 to 8 using 2-bromo-5-hydroxybenzaldehyde.
[0181] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.38-1.80 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 3.38
(3H, s, CH.sub.3O--), 3.52-4.23 (455H, m,
--(OCH.sub.2CH.sub.2).sub.n--, --OCH.sub.2CH<,
--CH.sub.2-phthalimide), 5.70 (0.6H, s, >CH--), 5.82 (0.4H, s,
>CH--), 6.95-7.21 (3H, m, arom. H), 7.70-7.86 (4H, m,
-phthalimide)
[0182] GPC analysis; number average molecular weight (Mn): 5548,
weight average molecular weight (Mw): 5670, polydispersity (Mw/Mn):
1.022
##STR00055##
Example 13
##STR00056##
[0184] A compound of formula (34) was synthesized in a manner
similar to Examples 1 to 4, and a compound of formula (35) was
obtained in the same manner as in Examples 5 to 8 using
3-fluoro-4-hydroxybenzaldehyde.
[0185] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.89 (2H, m, --CH.sub.2CH.sub.2-phthalimide), 3.19 (1H, m,
--OCH.sub.2CH<), 3.38 (3H, s, CH.sub.3O--), 3.52-4.41 (456H, m,
--(OCH.sub.2CH.sub.2).sub.n--, --OCH.sub.2CH<,
--CH.sub.2CH.sub.2CH.sub.2-phthalimide), 5.34 (0.8H, s, >CH--),
5.42 (0.2H, s, >CH--), 6.95-7.25 (3H, m, arom. H) 7.70-7.86 (4H,
m, -phthalimide)
[0186] GPC analysis; number average molecular weight (Mn): 5498,
weight average molecular weight (Mw): 5619, polydispersity (Mw/Mn):
1.022
##STR00057##
Example 14
[0187] A compound of formula (36) was obtained in the same manner
as in Examples 5 to 8 using the compound of formula (34) and
2-bromo-5-hydroxybenzaldehyde.
[0188] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.89 (2H, m, --CH.sub.2CH.sub.2-phthalimide), 3.19 (1H, m,
--OCH.sub.2CH<), 3.38 (3H, s, CH.sub.3O--), 3.52-4.41 (456H, m,
--(OCH.sub.2CH.sub.2).sub.n--, --OCH.sub.2CH<,
--CH.sub.2CH.sub.2CH.sub.2-phthalimide), 5.61 (0.8H, s, >CH--),
5.68 (0.2H, s, >CH--), 6.78-7.40 (3H, m, arom. H), 7.70-7.86
(4H, m, -phthalimide)
[0189] GPC analysis; number average molecular weight (Mn): 5564,
weight average molecular weight (Mw): 5686, polydispersity (Mw/Mn):
1.022
##STR00058##
Example 15
##STR00059##
[0191] A compound of formula (38) was obtained by removing the
tert-butyl group using hydrochloric acid from the compound of
formula (37) synthesized according to the method described in
JP-A-2010-248504.
[0192] .sup.1H-NMR (D.sub.2O, internal standard TMS); .delta.
(ppm): 3.14 (2H, t, NH.sub.2CH.sub.2--), 3.40-4.00 (452H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--)
NH.sub.2(CH.sub.2).sub.2--(OCH.sub.2CH.sub.2).sub.n--OH (31)
n=about 113
Example 16
[0193] A compound of formula (39) was obtained by allowing to react
the compound of formula (38) with 5-azidopentanoic anhydride.
[0194] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.60-1.74 (4H, m,
--CH.sub.2CH.sub.2CH.sub.2CH.sub.2N.sub.3), 2.18 (2H, t,
--CH.sub.2CH.sub.2CH.sub.2CH.sub.2N.sub.3), 3.29 (2H, t,
--CH.sub.2CH.sub.2CH.sub.2CH.sub.2N.sub.3), 3.40-3.85 (454H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--, --CONHCH.sub.2--), 6.30
(1H, brs, --CONH--)
##STR00060##
Example 17
[0195] A compound of formula (40) was obtained by allowing to react
the compound of formula (39) with methanesulfonyl chloride in
toluene in the presence of triethylamine in a manner similar to
Example 7.
[0196] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.60-1.74 (4H, m,
--CH.sub.2CH.sub.2CH.sub.2CH.sub.2N.sub.3), 2.18 (2H, t,
--CH.sub.2CH.sub.2CH.sub.2CH.sub.2N.sub.3) 3.08 (3H, s,
--OSO.sub.2CH.sub.3), 3.29 (2H, t,
--CH.sub.2CH.sub.2CH.sub.2CH.sub.2N.sub.3), 3.40-3.85 (452H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--, --CONHCH.sub.2--),
4.37-4.39 (2H, m, --CH.sub.2OSO.sub.2CH.sub.3), 6.30 (1H, brs,
--CH.sub.2CONH--)
##STR00061##
Example 18
[0197] A compound of formula (41) was obtained using
3-fluoro-4-hydroxybenzaldehyde and the compound of formula (40) in
the same manner as in Examples 1 to 5 and 8.
[0198] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.38-1.80 (10H, m, >CHCH.sub.2CH.sub.2CH.sub.2--,
--CH.sub.2CH.sub.2CH.sub.2CH.sub.2N.sub.3), 2.18 (2H, t,
--CH.sub.2CH.sub.2CH.sub.2CH.sub.2N.sub.3), 3.28-4.23 (461H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--,
--CH.sub.2CH.sub.2CH.sub.2CH.sub.2N.sub.3,
--CH.sub.2CONHCH.sub.2--, --OCH.sub.2CH<,
--CH.sub.2-phthalimide), 5.70 (0.6H, s, >CH--), 5.82 (0.4H, s,
>CH--), 6.30 (1H, brs, --CH.sub.2CONH--), 6.95-7.21 (3H, m,
arom. H), 7.70-7.86 (4H, m, -phthalimide)
##STR00062##
Example 19
[0199] A compound of formula (42) was obtained by deprotection of
the phthalimide group from the compound of formula (41) in the same
manner as in Example 9, followed by allowing to react with
iodoacetic anhydride.
[0200] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.38-1.80 (1014, m, >CHCH.sub.2CH.sub.2--,
--CH.sub.2CH.sub.2CH.sub.2CH.sub.2N.sub.3), 2.18 (2H, t,
--CH.sub.2CH.sub.2CH.sub.2CH.sub.2N.sub.3), 3.28-4.23 (463H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--,
--CH.sub.2CH.sub.2CH.sub.2N.sub.3, --CH.sub.2CONHCH.sub.2--,
ICH.sub.2CONHCH.sub.2--, ICH.sub.2CONHCH.sub.2--,
--OCH.sub.2CH<), 5.70 (0.6H, s, >CH--), 5.82 (0.4H, s,
>CH--), 6.30 (1H, brs, --CH.sub.2CONH--), 6.96 (1H, brs,
ICH.sub.2CONHCH.sub.2--), 6.95-7.21 (3H, m, arom. H)
[0201] GPC analysis; number average molecular weight (Mn): 5679,
weight average molecular weight (Mw): 5815, polydispersity (Mw/Mn):
1.024
##STR00063##
Example 20
##STR00064##
[0203] A compound of formula (44) was obtained by allowing to react
the compound of formula (43) synthesized according to the method
described in JP-A-2004-197077 with methanesulfonyl chloride in the
same manner as in Example 7.
[0204] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 3.08 (3H, s, --OSO.sub.2CH.sub.3), 3.38 (6H, s,
CH.sub.3O--), 3.40-4.00 (903H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--,
--(OCH.sub.2CH.sub.2).sub.n--OCH<), 4.26-4.42 (2H, m,
--CH.sub.2OSO.sub.2CH.sub.3)
##STR00065##
Example 21
[0205] A compound of formula (45) was obtained using
3-fluoro-4-hydroxybenzaldehyde and the compound of formula (44) in
the same manner as in Examples 1 to 5 and 8.
[0206] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.38-1.80 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 3.38
(6H, s, CH.sub.3O--), 3.40-4.23 (910H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--,
--(OCH.sub.2CH.sub.2).sub.n--OCH<, --OCH.sub.2CH<,
--CH.sub.2-phthalimide), 5.70 (0.6H, s, >CH--) 5.82 (0.4H, s,
>CH--), 6.95-7.21 (3H, m, arom. H), 7.70-7.86 (4H, m,
-phthalimide)
[0207] GPC analysis; number average molecular weight (Mn): 9761,
weight average molecular weight (Mw): 9986, polydispersity (Mw/Mn):
1.023
##STR00066##
Example 22
##STR00067##
[0209] A compound of formula (47) was obtained by allowing to react
the compound of formula (46) synthesized according to the method
described in JP-A-2004-197077 with acetic anhydride in the presence
of triethylamine and 4-dimethylaminopyridine.
[0210] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 2.08 (6H, s, CH.sub.3CO--), 3.40-4.00 (901H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--,
--(OCH.sub.2CH.sub.2).sub.n--OCH<, --CH.sub.2OCH.sub.2Ph), 4.22
(4H, t, CH.sub.3CO.sub.2CH.sub.2--), 4.54 (2H, s,
--CH.sub.2OCH.sub.2Ph), 7.27-7.38 (5H, m,
--CH.sub.2OCH.sub.2Ph)
##STR00068##
Example 23
[0211] A compound of formula (48) was obtained by removing the
benzyl group from the compound of formula (47) according to the
method described in JP-A-2004-197077, followed by allowing to react
with methanesulfonyl chloride in a manner similar to Example 7.
[0212] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 2.08 (6H, s, CH.sub.3CO--), 3.08 (3H, s,
--OSO.sub.2CH.sub.3), 3.40-4.00 (899H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--,
--(OCH.sub.2CH.sub.2).sub.n--OCH<), 4.22 (4H, t,
CH.sub.3CO.sub.2CH.sub.2--), 4.26-4.42 (2H, m,
--CH.sub.2OSO.sub.2CH.sub.3)
##STR00069##
Example 24
[0213] A compound of formula (49) was obtained using
3-fluoro-4-hydroxybenzaldehyde and the compound of formula (48) in
the same manner as in Examples 1 to 5 and 8.
[0214] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.38-1.80 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 2.08
(6H, s, CH.sub.3CO--), 3.40-4.23 (910H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--,
--(OCH.sub.2CH.sub.2).sub.n--OCH>, --OCH.sub.2CH>,
--CH.sub.2-phthalimide, CH.sub.3CO.sub.2CH.sub.2--), 5.70 (0.6H, s,
>CH--), 5.82 (0.4H, s, >CH--), 6.95-7.21 (3H, m, arom. H),
7.70-7.86 (4H, m, -hthalimide)
##STR00070##
Example 25
[0215] A compound of formula (50) was obtained by deprotection of
the phthalimide group using ethylene diamine monohydrate and the
removal of the acetyl group using an aqueous sodium hydroxide
solution from the compound of formula (49), followed by allowing to
react with N-succinimidyl 3-maleimidopropionate in the same manner
as in Example 10.
[0216] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.40-1.81 (614, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 2.44
(2H, t, --CH.sub.2CH.sub.2-maleimide), 3.27-3.37 (2H, m,
--CH.sub.2NHCO--), 3.40-4.23 (910H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--,
--(OCH.sub.2CH.sub.2).sub.n--OCH<, --OCH.sub.2CH<,
--CH.sub.2CH.sub.2-maleimide), 5.70 (0.6H, s, >CH--), 5.82
(0.4H, s, >CH--), 6.15 (1H, brs, --NHCO--), 6.70 (2H, s,
-maleimide), 6.95-7.21 (3H, m, arom. H)
##STR00071##
Example 26
[0217] A compound of formula (51) was obtained by allowing to react
the compound of formula (50) with N,N'-disuccinimidyl carbonate in
dichlormethane in the presence of triethylamine.
[0218] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm):
[0219] 1.40-1.81 (6H, m, >CHCH.sub.1CH.sub.2CH.sub.2--), 2.44
(2H, t, --CH.sub.2CH.sub.2-maleimide), 2.84 (8H, s, -succinimide),
3.27-3.37 (2H, m, --CH.sub.2NHCO--), 3.40-4.23 (906H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2,
--(OCH.sub.2CH.sub.2).sub.n--OCH<, --OCH.sub.2CH<,
--CH.sub.2CH.sub.2-maleimide), 4.44-4.48 (4H, m,
--CH.sub.2O--COO-succinimide), 5.70 (0.6H, s, >CH--), 5.82
(0.4H, s, >CH--), 6.15 (1H, brs, --NHCO--), 6.70 (2H, s,
-maleimide), 6.95-7.21 (3H, m, arom. H)
[0220] GPC analysis; number average molecular weight (Mn): 9955,
weight average molecular weight (Mw): 10204, polydispersity
(Mw/Mn): 1.025
##STR00072##
Example 27
##STR00073##
[0222] A compound of formula (53) was obtained by allowing to react
a compound of formula (52) synthesized by polymerizing ethylene
oxide to pentaerythritol with methanesulfonyl chloride in the same
manner as in Example 7.
[0223] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 3.08 (12H, s, --OSO.sub.2CH.sub.3), 3.47-3.85 (1800H, m,
--(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--), 4.37-4.39 (8H, m,
--CH.sub.2OSO.sub.2CH.sub.3)
##STR00074##
Example 27
[0224] A compound of formula (54) was obtained using
3-fluoro-4-hydroxybenzaldehyde and the compound of formula (53) in
the same manner as in Examples 1 to 5 and 8.
[0225] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.38-1.80 (24H, m, >CHCH.sub.2CH.sub.2CH.sub.2--),
3.52-4.23 (1828H, m, --(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--,
--OCH.sub.2CH<, --CH.sub.2-phthalimide), 5.70 (2.4H, s,
>CH--), 5.82 (1.6H, s, >CH--), 6.95-7.21 (12H, m, arom. H)
7.70-7.86 (16H, m, -phthalimide)
[0226] GPC analysis; number average molecular weight (Mn): 19645,
weight average molecular weight (Mw): 20136, polydispersity
(Mw/Mn): 1.025
##STR00075##
Example 28
[0227] Each of the compounds (20 mg) of formula (29), formula (32),
formula (33), formula (35) and formula (36) was dissolved in MES
deuterated water buffer (1 mL) of pD 5.5 and in HEPES deuterated
water buffer (1 mL) of pD 7.4, and allowed to stand in a
thermostatic bath at 37.degree. C. FIG. 1 and FIG. 2 show the
measurement results of hydrolysis rates at pD 5.5 and pD 7.4,
respectively.
[0228] As shown in FIG. 1, the hydrolysis rate half-lives
(t.sub.1/2) of the compounds of formula (29), formula (32), formula
(33), formula (35) and formula (36) at pD 5.5 and 37.degree. C.
were 2 hours, 12 hours, 30 days, 24 hours and 6 months,
respectively. Further, as shown in FIG. 2, at pD 7.4 and 37.degree.
C., the hydrolysis rate half-lives (t.sub.1/2) of the compounds of
formula (29) and formula (32) were 65 hours and 18 days,
respectively, the hydrolysis of approximately 17% was observed for
18 days for the compound of formula (35), and no hydrolysis was
observed even after 18 days for the compounds of formula (33) and
the formula (36).
Example 29
[0229] Into a 100 mL three-necked flask equipped with a
thermometer, a nitrogen inlet tube, a stirrer and a condenser tube
were charged the compound of formula (26) (1.10 g, 3.00 mmol),
methanol (53 g) and ethylenediamine monohydrate (5.86 g, 75.0
mmol), and the reaction was performed at 40.degree. C. for 4 hours.
The mixture was cooled to room temperature, diluted with an aqueous
10% by weight sodium chloride solution, and extracted with
dichloromethane. The organic layer was washed with an aqueous 10%
by weight sodium chloride solution, and dried over anhydrous sodium
sulfate. After filtration, the solvent was distilled off under a
reduced pressure to obtain a compound of formula (56).
[0230] .sup.1H-NMR (CD.sub.3OD, internal standard TMS); .delta.
(ppm): 1.44-1.80 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 2.77
(2H, 1, --CH.sub.2--NH.sub.2), 3.55-4.31 (3H, m,
--OCH.sub.2CH<), 5.70 (0.6H, s, >CH--), 5.81 (0.4H, s,
>CH--), 6.89-6.94 (2H, m, arom. H), 7.29-7.37 (2H, m, arom.
H)
##STR00076##
Example 30
[0231] Into a 100 ml, three-necked flask equipped with a
thermometer, a nitrogen inlet tube and a stirrer were charged the
compound of formula (56) (593 mg, 2.50 mmol) and dehydrated
methanol (20 g) and the mixture was stirred while adding dropwise a
solution obtained by dissolving ethyl trifluoroacetate (426 mg,
3.00 mmol) in dehydrated methanol (20 g). After the completion of
the dropwise addition, the reaction was performed at 25.degree. C.
for 2 hours. The solvent was distilled off under a reduced
pressure, and the residue was dried under a reduced pressure to
obtain a compound of formula (57).
[0232] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.44-1.80 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--),
3.57-4.26 (5H, m, --OCH.sub.2CH<, --CH.sub.2--NHCOCF.sub.3),
5.71 (0.6H, s, >CH--), 5.82 (0.4H, s, >CH--), 6.79-6.82 (2H,
m, arom. H), 7.31-7.35 (3H, m, arom. H, --NHCOCF.sub.3)
##STR00077##
Example 31
##STR00078##
[0234] A compound of formula (59) was obtained by allowing to react
the compound of formula (58) synthesized according to the method
described in JP-A-2010-138388 with methanesulfonyl chloride in the
same manner as in Example 7, followed by removing the tert-butyl
group using hydrochloric acid.
[0235] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 2.68 (1H, t, --OH), 3.08 (3H, s, --OSO.sub.2CH.sub.3),
3.52-3.85 (448H, m, --(OCH.sub.2CH.sub.2).sub.n--OCH.sub.2--),
4.37-4.39 (2H, m, --CH.sub.2OSO.sub.2CH.sub.3)
[0236] GPC analysis; number average molecular weight (Mn): 5195,
weight average molecular weight (Mw): 5309, polydispersity (Mw/Mn):
1.022
Example 32
##STR00079##
[0238] Into a 100 mL three-necked flask equipped with a
thermometer, a nitrogen inlet tube, a stirrer and a condenser tube
were charged the compound of formula (59) (5.00 g, 1.00 mmol), the
compound of formula (57) (500 mg, 1.50 mmol), potassium carbonate
(691 mg, 5.00 mmol) and acetonitrile (25 g), and the reaction was
performed at 80.degree. C. for 4 hours. After distilled off the
solvent under a reduce pressure, the residue was dissolved in ethyl
acetate (100 g), and the solution was filtered. Crystallization was
performed by adding hexane (100 g), and after filtration, the
crystals were dried under a reduced pressure to obtain a compound
of formula (60).
[0239] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.40-1.81 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 2.68
(1H, t, --OH), 3.52-4.25 (455H, m, --(OCH.sub.2CH.sub.2).sub.n--,
--OCH.sub.2CH<, --CH.sub.2--NHCOCF.sub.3), 5.72 (0.6H, s,
>CH--), 5.84 (0.4H, s, >CH--), 6.89-6.91 (2H, m, arom. H),
7.31-7.39 (3H, m, arom. H, --NHCOCF.sub.3)
[0240] GPC analysis; number average molecular weight (Mn): 5432,
weight average molecular weight (Mw): 5552, polydispersity (Mw/Mn):
1.022
##STR00080##
Example 33
[0241] Into a 100 mL three-necked flask equipped with a
thermometer, a nitrogen inlet tube and a stirrer were charged the
compound of formula (60) (1.00 g, 0.200 mmol) and dichloromethane
(5 g), and glutaric anhydride (34.2 mg, 0,300 mmol), triethylamine
(30.4 mg, 0,300 mmol) and 4-dimethylaminopyridine (12 mg, 0.015
mmol) were added thereto, and the reaction was performed at
25.degree. C. for 6 hours. After filtration, the solvent was
distilled off under a reduced pressure. The residue was dissolved
in methanol (2.5 g), and a 1M aqueous potassium carbonate solution
(5 g) was added thereto, and the reaction was performed at
25.degree. C. for 3 hours. The mixture was diluted with an aqueous
20% by weight sodium chloride solution, extracted with
dichloromethane, and the solvent was distilled off under a reduced
pressure. The residue was dissolved in ethyl acetate (50 g), dried
over anhydrous sodium sulfate, filtered, and crystallized by adding
hexane (50 g). After filtration, the crystals were dried under a
reduced pressure to obtain a compound of formula (61).
[0242] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.40-1.81 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 1.97
(2H, quin, --CH.sub.2CH.sub.2CH.sub.2COOH), 2.38-2.46 (4H, m,
--CH.sub.2CH.sub.2CH.sub.2COOH), 2.71 (2H, t,
--CH.sub.2--NH.sub.2), 3.52-4.27 (455H, m,
--(OCH.sub.2CH.sub.2).sub.n--, --OCH.sub.2CH<,
--CH.sub.2O--COCH.sub.2--), 5.72 (0.6H, s, >CH--), 5.84 (0.4H,
s, >CH--), 6.89-6.91 (2H, m, arom. H), 7.35-7.39 (2H, m, arom.
H)
[0243] GPC analysis; number average molecular weight (Mn): 5449,
weight average molecular weight (Mw): 5569, polydispersity (Mw/Mn):
1.022
##STR00081##
Example 34
[0244] Into a 300 mL three-necked flask equipped with a
thermometer, a nitrogen inlet tube, a stirrer, a Dean-stark tube
and a condenser tube were charged 1,2,6-hexanetriol (2.01 g, 15.0
mmol), 4-hydroxybenzaldehyde (1.22 g, 10.0 mmol), p-toluenesulfonic
acid monohydrate (19.0 mg, 0.100 mmol) and toluene (183 g), and the
reaction was performed for 4 hours while removing by-produced water
by azeotropic distillation with toluene. Triethylamine (20.2 mg,
0.200 mmol) was added thereto and after stirring for a while, the
mixture was washed with an aqueous 10% by weight sodium chloride
solution, and the organic layer was dried over anhydrous sodium
sulfate. After filtration, the solvent was distilled off under a
reduced pressure to obtain a compound of formula (62).
[0245] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.42-1.80 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--),
3.57-4.26 (5H, m, --OCH.sub.2CH<, --CH.sub.2--OH), 5.71 (0.61H,
s, >CH--), 5.82 (0.41, s, >CH--), 6.79-6.82 (2H, m, arom, H)
7.31-7.35 (2H, m, arom. H)
##STR00082##
Example 35
[0246] Into a 100 mL three-necked flask equipped with a
thermometer, a nitrogen inlet tube, a stirrer and a condenser tube
were charged the compound of formula (28) (5.00 g, 1.00 mmol), the
compound of formula (62) (357 mg, 1.50 mmol), potassium carbonate
(691 mg, 5.00 mmol) and acetonitrile (25 g), and the reaction was
performed at 80.degree. C. for 4 hours. After distilled off the
solvent under a reduce pressure, the residue was dissolved in ethyl
acetate (100 g) and the solution was filtered. Crystallization was
performed by adding hexane (100 g), and after filtration, the
crystals were dried under a reduced pressure to obtain a compound
of formula (63).
[0247] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.40-1.81 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 3.38
(3H, s, CH.sub.3O--), 3.52-4.25 (455H, m,
--(OCH.sub.2CH.sub.2).sub.n--, --OCH.sub.2CH<, --CH.sub.2--OH),
5.72 (0.6H, s, >CH--), 5.84 (0.4H, s, >CH--), 6.89-6.91 (2H,
m, arom. H), 7.35-7.39 (2H, m, arom. H)
[0248] GPC analysis; number average molecular weight (Mn): 5332,
weight average molecular weight (Mw): 5449, polydispersity (Mw/Mn):
1.022
##STR00083##
Example 36
[0249] A compound of formula (64) was obtained by allowing to react
the compound of formula (63) with N,N'-disuccinimidyl carbonate in
dichloromethane in the presence of triethylamine.
[0250] .sup.1H-NMR (CDCl.sub.3, internal standard TMS); .delta.
(ppm): 1.45-1.87 (6H, m, >CHCH.sub.2CH.sub.2CH.sub.2--), 2.84
(4H, two singlets, -succinimide), 3.38 (3H, s, CH.sub.3O--),
3.52-4.38 (455H, m, --(OCH.sub.2CH.sub.2).sub.n--,
--OCH.sub.2CH<, --CH.sub.2O--COO-succinimide), 5.72 (0.6H, s,
>CH--), 5.84 (0.4H, s, >CH--), 6.89-6.91 (2H, m, arom. H),
7.35-7.39 (2H, m, arom. H)
[0251] GPC analysis; number average molecular weight (Mn): 5470,
weight average molecular weight (Mw): 5590, polydispersity (Mw/Mn):
1.022
##STR00084##
[0252] While the invention has been described in detail and with
reference to specific embodiments thereof, it will be apparent to
those skilled in the art that various changes and modifications can
be made therein without departing from the spirit and scope of the
invention.
[0253] This application is based on a Japanese patent application
filed on Mar. 31, 2014 (Japanese Patent Application No. 2014-72356
and Japanese patent application filed on Sep. 22, 2014 (Japanese
Patent Application No. 2014-193039, and the whole contents thereof
are incorporated herein by reference. Also, all the references
cited herein are incorporated as a whole.
* * * * *