U.S. patent application number 16/847394 was filed with the patent office on 2020-07-30 for method for preparing pyrrolo[3,2,-d]pyrimidine compound, and intermediates thereof.
The applicant listed for this patent is CHIA TAI TIANQING PHARMACEUTICAL GROUP CO., LTD.. Invention is credited to Zhaozhong DING, Yinghu HU, Fei SUN, Ling YANG, Rui ZHAO, Yilong ZHOU.
Application Number | 20200239484 16/847394 |
Document ID | 20200239484 / US20200239484 |
Family ID | 59500148 |
Filed Date | 2020-07-30 |
Patent Application | download [pdf] |
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United States Patent
Application |
20200239484 |
Kind Code |
A1 |
DING; Zhaozhong ; et
al. |
July 30, 2020 |
METHOD FOR PREPARING PYRROLO[3,2,-D]PYRIMIDINE COMPOUND, AND
INTERMEDIATES THEREOF
Abstract
The present invention relates to a method for preparing a
pyrrolo[3,2-d]pyrimidine compound (the compound represented by
formula I), and corresponding intermediates. ##STR00001##
Inventors: |
DING; Zhaozhong; (Shanghai,
CN) ; SUN; Fei; (Shanghai, CN) ; HU;
Yinghu; (Shanghai, CN) ; ZHOU; Yilong;
(Shanghai, CN) ; ZHAO; Rui; (Jiangsu, CN) ;
YANG; Ling; (Jiangsu, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CHIA TAI TIANQING PHARMACEUTICAL GROUP CO., LTD. |
Jiangsu |
|
CN |
|
|
Family ID: |
59500148 |
Appl. No.: |
16/847394 |
Filed: |
April 13, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16075300 |
Aug 3, 2018 |
10654856 |
|
|
PCT/CN2017/072893 |
Feb 4, 2017 |
|
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16847394 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C07D 487/04
20130101 |
International
Class: |
C07D 487/04 20060101
C07D487/04 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 5, 2016 |
CN |
201610082028.3 |
Claims
1. A compound of formula VI: ##STR00030## wherein R.sub.1 and
R.sub.2 are independently selected from the group consisting of
C.sub.1-4 alkyl, or R.sub.1 and R.sub.2 together with the N atom
attached thereto form 4-8 membered heterocycloalkyl, wherein the
heterocycloalkyl is optionally substituted with one or more
substituents independently selected from hydroxyl, halogen,
C.sub.1-4 alkyl and C.sub.1-4 alkoxy.
2. The compound of formula VI according to claim 1, wherein R.sub.1
and R.sub.2 are independently selected from the group consisting of
C.sub.1-4 alkyl.
3. The compound of formula VI according to claim 1, wherein R.sub.1
and R.sub.2 together with the N atom attached thereto form 4-8
membered heterocycloalkyl, wherein the heterocycloalkyl is
optionally substituted with one or more substituents independently
selected from hydroxyl, halogen, C.sub.1-4 alkyl and C.sub.1-4
alkoxy.
4. The compound of formula VI according to claim 1, wherein
NR.sub.1R.sub.2 of formula VI is selected from the group consisting
of ##STR00031##
5. The compound of formula VI according to claim 1, selected from:
##STR00032## ##STR00033## ##STR00034##
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a division of U.S. patent application
Ser. No. 16/075,300, filed on Aug. 3, 2018, which is a national
phase of International Application No. PCT/CN2017/072893, filed on
Feb. 4, 2017, which claims priority to Chinese Patent Application
No. 201610082028.3, filed on Feb. 5, 2016, each of which are
incorporated herein by reference in their entireties.
TECHNICAL FIELD
[0002] The present invention relates to the field of medicinal
chemistry and specifically relates to a process for preparing
pyrrolo[3,2-d]pyrimidine compound and the intermediate thereof.
BACKGROUND
[0003] Toll-like receptor is expressed by various immune cells and
recognizes high reserved structural motifs: Pathogen Associated
Molecular Pattern (PAMP) expressed by microorganism pathogens or
Damage Associated Molecular Patterns (DAMP) released by dead cells.
PAMP or DAMP stimulates Toll-like receptor to trigger signal
cascade which induces the activations of transcriptional factors
like AP-1, NF--KB and interferon regulators (pulse response
function). It results in various cell responses, including
productions of interferons, proinflammatory cytokines and effector
cytokines, whereby immune response is produced. By far, 13 types of
Toll-like receptors have been discovered in mammal. Toll-like
receptors 1, 2, 4, 5 and 6 are mainly expressed on the cell surface
while Toll-like receptors 3, 7, 8 and 9 are expressed in the
endosome. Different Toll-like receptors recognize ligands derived
from different pathogens. Toll-like receptor 7 (TLR7) is mainly
expressed by plasmaeytoid dendritic cells (pDC), and recognized via
ligand to induce the secretion of interferon .alpha. (IFN-.alpha.).
Toll-like receptor 7 (TLR7) and Toll-like receptor 8 (TLR8) are
highly homologous and therefore the ligand of TLR7 in most cases is
also that of TLR8. TLR8 stimulation mainly induces the productions
of cytokines like tumor necrosis factor .alpha. (TNF-.alpha.) and
chemoattractant. Interferon .alpha. is one of the medicines for
treating chronic hepatitis B or hepatitis C while TNF-.alpha. is a
proinflammatory cytokine, of which the over secretion will result
severe side effects. There have been reported several TLR7
agonists, like imiquimod (British Journal of Dermatology 2003; 149
(Suppl. 66): 5-8), resiquimod (Antiviral Research 64 (2004) 79-83),
GS-9620 (Gastroenterology (2013), 144(7), 1508-1517). Nevertheless,
it is desirable to have novel TLR7 agonists with better
selectivity, activity and safety.
[0004] Chinese Patent Application No. 201410405136.0 which is
incorporated in its entirety by reference herein discloses a series
of pyrrolopyrimidine compounds as TLR7 agonist.
SUMMARY
[0005] In an aspect, provided is a process for preparing the
compound of formula I:
##STR00002##
the process comprises dehydroxylating the compound of formula VI to
obtain the compound of formula I:
##STR00003##
wherein R.sub.1 and R.sub.2 are independently selected from the
group consisting of C.sub.1-4 alkyl, or R.sub.1 and R.sub.2
together with the N atom attached thereto form 4.about.8 membered
heterocycloalkyl, wherein the heterocycloalkyl is optionally
substituted with one or more substituents independently selected
from the group consisting of hydroxyl, halogen, C.sub.1-4 alkyl and
C.sub.1-4 alkoxy.
DETAILED DESCRIPTION
Definition
[0006] Unless stated otherwise, the terms and phrases used herein
have the following meaning. A specific term or phrase shall not be
considered as unclear or indefinite when it is not specifically
defined. It should be understood according to the general meaning.
The trade name used herein refers to the corresponding product or
the active ingredient.
[0007] Unless specifically defined otherwise, proportion (including
percentage) or part is calculated based on weight herein.
[0008] When used with a numerical variable, the term "approximate"
or "about" usually refers to the value of the variable and all the
values of the variable within the experimental error (for example,
within an average 95% confidence interval) or within .+-.10% of the
specified value, or a wider range.
[0009] The expression "comprise" or its synonyms "contain",
"include", "have" or the like is open-ended, which does not exclude
other unlisted elements, steps or ingredients. The expression
"consist of" excludes any unlisted elements, steps or ingredients.
The expression "substantially consist of" refers to specified
elements, steps or ingredients within a given range, together with
optional elements, steps or components which do not substantively
affect the basic and novel feature of the claimed subject matter.
It should be understood that the expression "comprise" encompasses
the expressions "substantially consist of" and "consist of".
[0010] The term "optional" or "optionally" means the event
described subsequent thereto may or may not happen. This term
encompasses the cases that the event may or may not happen.
[0011] The expression C.sub.m-n used herein means that it has m-n
carbon atoms. For example, "C.sub.1-4alkyl" means said alkyl has
1-4 carbon atoms.
[0012] The numerical range herein refers to each of the integers
therein and the subranges formed by the integers. For example,
"C.sub.1-4" means said group may have 1 carbon atom, 2 carbon
atoms, 3 carbon atoms or 4 carbon atoms. Accordingly, "C.sub.1-4
alkyl" encompasses "C.sub.2-3 alkyl", "C.sub.1-3 alkyl", "C.sub.2-4
alkyl", as well as C.sub.1 alkyl, C.sub.2 alkyl, C.sub.3 alkyl,
C.sub.4alkyl or the like.
[0013] The term "substituted" means that one or more hydrogen atoms
on a given atom are replaced by a substituent, provided that the
valence of the particular atom is normal and the compound after
substitution is stable.
[0014] Unless stated otherwise, the term "hetero" means heteroatom
or hetero-radical (i.e. a radical containing heteroatom), i.e. the
atoms beyond carbon and hydrogen atoms or the radical containing
such atoms. Preferably, the heteroatom is independently selected
from the group consisting O, N, S etc. In an embodiment wherein two
or more heteroatoms are involved, the two or more heteroatoms may
be the same or part or all of the two or more heteroatoms may be
different.
[0015] The term "alkyl" refers to a linear or branched saturated
aliphatic hydrocarbyl group consisting of carbon and hydrogen
atoms, which is linked to rest of the molecule via a single bond.
Non-limiting examples of C.sub.1-4alkyl comprise but not limited to
methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl,
tert-butyl or the like.
[0016] The term "C.sub.1-4 alkoxy" refers to "C.sub.1-4 alkyl"
which is connected to the rest of the molecule via "--O--", wherein
the "C.sub.1-4 alkyl" is defined as above.
[0017] The term "halo" or "halogen" refers to F, Cl, Br or I.
[0018] The term "hydroxyl" refers to --OH group.
[0019] The N atom in the expression "R.sub.1 and R.sub.2 together
with the N atom attached thereto" refers to the N atom in the
moiety
##STR00004##
in the formula.
[0020] The term "heterocycloalkyl" refers to a saturated monocyclic
or polycyclic system group, wherein part of the ring atoms are
heteroatoms selected from the group consisting of N, O, S, and rest
of the ring atoms are C. Accordingly, the term "4.about.8 membered
heterocycloalkyl" refers to the heterocycloalkyl containing 4-8
ring atoms in the system, wherein one or more ring atoms are
heteroatoms selected from the group consisting of N, O, S.
"4.about.8 membered heterocycloalkyl" encompasses "4.about.7
membered", "4.about.6 membered", "5.about.7 membered"
heterocycloalkyl, for example but not limited to 4, 5, 6, 7, 8
membered heterocycloalkyl. The examples of 4 membered
heterocycloalkyl comprise but not limited to azetidinyl; the
examples of 5 membered heterocycloalkyl comprise but not limited to
pyrrolidinyl, isoxazolidinyl, oxazolidinyl, isothiazolidinyl,
thiazolidinyl, imidazolidinyl; the examples of 6 membered
heterocycloalkyl comprise but not limited to piperidinyl,
morpholinyl, piperazinyl; and the examples of 7 membered
heterocycloalkyl comprise but not limited to azacycloheptanyl,
oxaazabicyclo[2.2.1]heptyl, or the like.
[0021] The term "one or more" refers to one, two, three, four,
five, six, seven, eight or more.
[0022] The following abbreviations are used herein: SEM:
2-(trimethylsilyl)ethoxymethyl; SEM-Cl
2-(trimethylsilyl)ethoxymethyl chloride; DIPEA:
diisopropylethylamine; TFA: trifluoroacetic acid; DMF:
N,N-dimethylformamide; n-BuOH: n-butanol.
Process for Preparing the Compound of Formula I
[0023] In an aspect, provided is a process for preparing the
compound of formula I, the process comprises dehydroxylating the
compound of formula VI to obtain the compound of formula I:
##STR00005##
wherein R.sub.1 and R.sub.2 are independently selected from the
group consisting of C.sub.1-4 alkyl, or R.sub.1 and R.sub.2
together with the N atom attached thereto form 4.about.8 membered
heterocycloalkyl, wherein the heterocycloalkyl is optionally
substituted with one or more substituents independently selected
from the group consisting of hydroxyl, halogen, C.sub.1-4 alkyl and
C.sub.1-4 alkoxy.
[0024] In an embodiment, the process for preparing the compound of
formula I according to the invention comprises the following
steps:
(a) reacting the compound of formula II with the compound of
formula III in the presence of base to obtain the compound of
formula IV
##STR00006##
(b) reacting the compound of formula IV with the compound of
formula V in the presence of reductant to obtain the compound of
formula VI
##STR00007##
(c) dehydroxylating the compound of formula VI to obtain the
compound of formula I
##STR00008##
wherein R.sub.1 and R.sub.2 are independently selected from the
group consisting of C.sub.1-4 alkyl, or R.sub.1 and R.sub.2
together with the N atom attached thereto form 4.about.8 membered
heterocycloalkyl, wherein the heterocycloalkyl is optionally
substituted with one or more substituents independently selected
from the group consisting of hydroxyl, halogen, C.sub.1-4 alkyl and
C.sub.1-4 alkoxy.
[0025] In an embodiment, the base is selected from the group
consisting of sodium carbonate, sodium bicarbonate, potassium
carbonate, potassium phosphate, potassium bicarbonate, cesium
carbonate, lithium hydroxide, sodium hydroxide, potassium
hydroxide, calcium hydroxide, magnesium hydroxide, barium
hydroxide, sodium methoxide, sodium ethoxide, sodium t-butoxide,
potassium t-butoxide, triethylamine, diisopropylethylamine,
pyridine, N,N-dimethylaminopyridine, piperidine,
N-methylpiperidine, morpholine, N-methylmorpholine and any
combination thereof, preferably sodium carbonate, potassium
carbonate, sodium hydroxide, potassium hydroxide and any
combination thereof, most preferably potassium carbonate.
[0026] In an embodiment, step (a) is performed in a solvent. In a
preferred embodiment, the solvent is isopropanol or a mixture of
isopropanol with water.
[0027] In an embodiment, the molar ratio of the compound of formula
II to the base is 1.0:1.0.about.3.0, preferably 1.0:1.0.about.1.5,
more preferably 1.0:1.2.
[0028] In an embodiment, the molar ratio of the compound of formula
II to the compound of formula III is 1.0:1.0.about.3.0, preferably
1.0:1.0.about.1.5, more preferably 1.0:1.2.about.1.5.
[0029] In an embodiment, the step (b) is performed in the presence
of acid. In another embodiment, the acid is selected from the group
consisting of hydrochloric acid, hydrobromic acid, phosphoric acid,
sulfuric acid, formic acid, acetic acid, propionic acid, citric
acid, fumaric acid, malic acid, succinic acid, salicylic acid,
maleic acid, trifluoroacetic acid and any combination thereof,
preferably acetic acid.
[0030] In an embodiment, in step (b), the molar ratio of the
compound of formula IV to the acid is 1.0:1.0.about.3.0, preferably
1.0:1.2.about.2.0, more preferably 1.0:1.5.
[0031] In an embodiment, the step (b) is conducted in a solvent. In
a preferred embodiment, the solvent is isopropanol or a mixture of
isopropanol with water.
[0032] In an embodiment, the reductant is selected from the group
consisting of BH.sub.3, NaBH.sub.4, NaBH.sub.3CN, NaBH(AcO).sub.3
and any combination thereof, preferably NaBH(AcO).sub.3.
[0033] In an embodiment, the molar ratio of the compound of formula
IV to the reductant is 1.0:1.0.about.3.0, preferably
1.0:1.2.about.2.0, more preferably 1.0:1.5.
[0034] In a preferred embodiment, the dehydroxylation is performed
in the presence of triethylsilane and trifluoroacetic acid.
[0035] In another preferred embodiment, the molar ratio of the
compound of formula VI to triethylsilane is 1:1.about.10,
preferably 1:2.about.8, more preferably 1:5.
[0036] In another preferred embodiment, the molar ratio of the
compound of formula VI to trifluoroacetic acid is 1:2.about.20,
preferably 1:5.about.15, more preferably 1:10.about.12.
[0037] In an embodiment, the step (c) is performed in a solvent. In
a preferred embodiment, the solvent is dichloromethane.
[0038] In another embodiment, the process for preparing the
compound of formula I according to the invention comprises the
following steps:
(a') reacting the compound of formula II with the compound of
formula III' in the presence of base to obtain the compound of
formula VI
##STR00009##
(b') dehydroxylating the compound of formula VI to obtain the
compound of formula I
##STR00010##
wherein R.sub.1 and R.sub.2 are independently selected from the
group consisting of C.sub.1-4 alkyl, or R.sub.1 and R.sub.2
together with the N atom attached thereto form 4.about.8 membered
heterocycloalkyl, wherein the heterocycloalkyl is optionally
substituted with one or more substituents independently selected
from the group consisting of hydroxyl, halogen, C.sub.1-4 alkyl and
C.sub.1-4 alkoxy.
[0039] In an embodiment, the base is selected from the group
consisting of sodium carbonate, sodium bicarbonate, potassium
carbonate, potassium phosphate, potassium bicarbonate, cesium
carbonate, lithium hydroxide, sodium hydroxide, potassium
hydroxide, calcium hydroxide, magnesium hydroxide, barium
hydroxide, sodium methoxide, sodium ethoxide, sodium t-butoxide,
potassium t-butoxide, triethylamine, diisopropylethylamine,
pyridine, N,N-dimethylaminopyridine, piperidine,
N-methylpiperidine, morpholine, N-methylmorpholine and any
combination thereof, preferably sodium carbonate, potassium
carbonate, sodium hydroxide, potassium hydroxide and any
combination thereof, most preferably potassium carbonate.
[0040] In an embodiment, the step (a') is performed in a solvent.
In a preferred embodiment, the solvent is methanol or a mixture of
methanol with water.
[0041] In an embodiment, the molar ratio of the compound of formula
II to the base is 1.0:1.0.about.3.0, preferably 1.0:1.0.about.1.5,
more preferably 1.0:1.2.
[0042] In an embodiment, the molar ratio of the compound of formula
II to the compound of formula III' is 1.0:1.0.about.3.0, preferably
1.0:1.0.about.1.5, more preferably 1.0:1.2.about.1.5.
[0043] In a preferred embodiment, the dehydroxylation is performed
in the presence of triethylsilane and trifluoroacetic acid.
[0044] In another preferred embodiment, the molar ratio of the
compound of formula VI to triethylsilane is 1:1.about.10,
preferably 1:2.about.8, more preferably 1:5.
[0045] In another preferred embodiment, the molar ratio of the
compound of formula VI to trifluoroacetic acid is 1:2.about.20,
preferably 1:5.about.15, more preferably 1:10.about.12.
[0046] In an embodiment, the step (b') is performed in a solvent.
In a preferred embodiment, the solvent is dichloromethane.
[0047] In an embodiment, the compound of formula V is selected
from
##STR00011##
preferably
##STR00012##
[0048] In a preferable embodiment, the compound of formula I is
selected from the compounds numbered as follows:
##STR00013## ##STR00014## ##STR00015##
Intermediate Compound and Preparation
[0049] Provided are the compound of formula II and the compound of
formula VI as intermediate:
##STR00016##
wherein R.sub.1 and R.sub.2 are independently selected from the
group consisting of C.sub.1-4 alkyl, or R.sub.1 and R.sub.2
together with the N atom attached thereto form 4.about.8 membered
heterocycloalkyl, wherein the heterocycloalkyl is optionally
substituted with one or more substituents independently selected
from the group consisting of hydroxyl, halogen, C.sub.1-4 alkyl and
C.sub.1-4alkoxy.
[0050] In an embodiment, the compound of formula VI is selected
from
##STR00017## ##STR00018## ##STR00019##
[0051] The compound of formula II according to the invention may be
prepared through the following process,
##STR00020##
wherein, reacting the compound of formula VII with SEM-Cl to obtain
the compound of formula VIII (preferably in DMF); reacting the
compound of formula VIII with aqueous ammonia to obtain the
compound of formula IX (preferably in isopropanol); subjecting the
compound of formula IX to substitution reaction with sodium
n-butoxide to form the compound of formula X (preferably in
n-BuOH); and removing SEM from the compound of formula X under the
action of TFA to obtain the compound of formula II (preferably in
TFA).
BENEFICIAL EFFECT
[0052] The preparing process according to the invention has mild
reaction conditions, for example the reaction may be conducted
under atmospheric pressure (e.g. about 1 atm), and the requirement
for reaction temperature is normal. The preparing process according
to the invention can also avoid the use of reagents with high cost
and risks and is particularly suitable for industrial
production.
EXAMPLES
[0053] To better understand the invention, further illustration
will be given below with reference to the following examples. The
specific examples, however, are not intended to limit the scope of
the present invention.
Preparation Example 1
[0054] The preparation example of the compound of formula I:
Preparation of
2-butoxy-7-(4-(pyrrolidin-1-ylmethyl)benzyl)-5H-pyrrolo[3,2-d]pyrimidin-4-
-amine (the Compound of Formula I of No. 1)
Preparation of
4-((4-amino-2-butoxy-5H-pyrrolo[3,2-d]pyrimidin-7-yl)-hydroxylmethyl)benz-
aldehyde (the Compound of Formula IV)
##STR00021##
[0056] To a three-necked flask were added terephthalic aldehyde
(790.64 mg, 5.82 mmol) and isopropanol (10 mL), followed by
addition of 2-butoxy-5H-pyrrolo[3,2-d]pyrimidin-4-amine (1.00 g,
4.85 mmol) with stirring. Stirring was performed for 10 min after
the system was cooled to 0.degree. C. Purified water (10 mL) and
potassium carbonate (804.17 mg, 5.82 mmol) were added, and the
reaction was performed at 25.degree. C. for 16 h until the raw
materials were depleted with the monitor by LCMS. After completion
of the reaction, solid was precipitated out. Filtration was
performed and the solid was slurried with 20 ml of purified water
and 30 ml (ethyl acetate/n-heptane=1/20) successively. Filtration
was performed and drying was conducted to give the title compound
as yellow solid (1.50 g, 4.41 mmol, yield: 90.9%).
[0057] .sup.1H NMR (400 MHz, methanol-d.sub.4) .delta. 9.94 (s,
1H), 7.86 (d, J=8.16 Hz, 2H), 7.72 (d, J=8.16 Hz, 2H), 7.12-7.17
(m, 1H), 6.19 (s, 1H), 4.28 (t, J=6.53 Hz, 2H), 1.68-1.77 (m, 2H),
1.44-1.54 (m, 2H), 0.97 (t, J=7.34 Hz, 3H).
Preparation of
(4-amino-2-butoxy-5H-pyrrolo[3,2-d]pyrimidin-7-yl)(4-(pyrrolidin-1-ylmeth-
yl)phenyl) methanol (the Compound of Formula VI-1)
##STR00022##
[0059] To 30 L clave were added the above obtained compound of
formula IV
4-((4-amino-2-butoxy-5H-pyrrolo[3,2-d]pyrimidin-7-yl)-hydroxylmethyl)benz-
aldehyde (450.0 g, 1.32 mol) and isopropanol (4.5 L). After
stirring for 5 min, glacial acetic acid (119.0 g, 1.98 mol) was
added. The system was stirred until it was cooled to 0-10.degree.
C. Pyrrolidine (112.4 g, 1.58 mol) was added dropwise during which
the temperature of the system was kept below 10.degree. C. After
addition, sodium triacetoxyborohydride (NaBH(AcO).sub.3) (420.0 g,
1.98 mol) was added in portions. The reaction was carried out at
10-20.degree. C. for 3 h until the raw materials were depleted with
the monitor by liquid chromatography. After the completion of
reaction, 5 L of purified water was added and the temperature of
the solution was lowered to about -10.degree. C. 12 L of 15%
aqueous ammonia was added during which the temperature of the
solution was kept below 0.degree. C. Solid was precipitated out
under stirring. Filtration was performed and the solid was slurried
with 2 L of water and 2 L.times.2 ethyl acetate successively.
Filtration was performed and drying was conducted at 40.degree. C.
under reduced pressure for 12 h to give the title compound as
yellow solid (465.0 g, 1.18 mol, yield 89.4%, moisture 0.9%).
[0060] .sup.1H NMR (400 MHz, methanol-d.sub.4) .delta. 7.46 (d,
J=7.91 Hz, 1H), 7.29 (d, J=8.03 Hz, 1H), 7.09 (s, 1H), 6.12 (s,
1H), 4.29 (t, J=6.53 Hz, 2H), 3.60 (s, 2H), 2.52 (br. s., 4H),
1.66-1.83 (m, 6H), 1.49 (d, J=7.53 Hz, 2H), 0.98 (t, J=7.40 Hz,
3H).
[0061] The compound of formula VI-1 can also be prepared according
to the following process:
Preparation of
(4-amino-2-butoxy-5H-pyrrolo[3,2-d]pyrimidin-7-yl)(4-(pyrrolidin-1-ylmeth-
yl)phenyl) methanol (the Compound of Formula VI-1)
##STR00023##
[0063] To the mixture of
2-butoxy-5H-pyrrolo[3,2-d]pyrimidin-4-amine (3.00 g, 14.55 mmol),
4-(pyrrolidin-1-ylmethyl)benzaldehyde (4.13 g, 21.82 mmol),
methanol (30 mL) and water (30 mL) was added potassium carbonate
(2.41 g, 17.46 mmol) with stirring. Then stirring was performed at
25.degree. C. for 12 h and raw materials were depleted with the
monitor by thin-layer chromatography. Solid was precipitated out
after completion of the reaction. 30 mL of water was added, and the
solid was filtered and dried to give the title compound as white
solid (3.50 g, 8.85 mmol, yield: 60.82%).
[0064] .sup.1H NMR (400 MHz, methanol-d.sub.4) .delta. 7.46 (d,
J=7.91 Hz, 1H), 7.29 (d, J=8.03 Hz, 1H), 7.09 (s, 1H), 6.12 (s,
1H), 4.29 (t, J=6.53 Hz, 2H), 3.60 (s, 2H), 2.52 (br. s., 4H),
1.66-1.83 (m, 6H), 1.49 (d, J=7.53 Hz, 2H), 0.98 (t, J=7.40 Hz,
3H).
Preparation of
2-butoxy-7-(4-(pyrrolidin-1-ylmethyl)benzyl)-5H-pyrrolo[3,2-d]pyrimidin-4-
-amine (the Compound of Formula I of No. 1)
##STR00024##
[0066] To 20 L clave were added the above obtained compound of
formula VI-1
(4-amino-2-butoxy-5H-pyrrolo[3,2-d]pyrimidin-7-yl)(4-(pyrrolidin-1-y-
lmethyl)phenyl)methanol (440.0 g, 1.11 mol) and dichloromethane
(7.0 L). The system was stirred until it was cooled to below
-15.degree. C. Triethylsilane (880 mL, 5.55 mol) was added dropwise
followed by trifluoroacetic acid (880 mL, 11.84 mol) dropwise
during which the temperature of the system was kept below
-10.degree. C. After addition, the reaction was carried out at
0.degree. C. for 2 h until the raw material point disappeared with
the monitor by liquid chromatography. After the completion of
reaction, the reaction liquid was concentrated to dryness, 2.2 L of
ethyl acetate was added and the system was cooled to below
0.degree. C. with stirring. Saturated sodium carbonate solution was
added to adjust pH to 9-10, during which the temperature was kept
below 10.degree. C. Filtration was performed and the obtained
filter cake was slurried with 2.2 L of water. Drying was conducted
under reduced pressure to give 550 g of
2-butoxy-7-(4-(pyrrolidin-1-ylmethyl)benzyl)-5H-pyrrolo[3,2-d]pyrimidin-4-
-amine (trifluoroacetate of the title compound) as white solid. The
obtained white solid was desalinated under alkaline condition to
give the title compound, which may be carried out, for example, by
conventional process.
[0067] .sup.1H NMR (400 MHz, methanol-d.sub.4) .delta. 7.27 (d,
J=8.0 Hz, 2H), 7.22 (d, J=8.0 Hz, 2H), 7.04 (s, 1H), 4.32 (t, J=6.6
Hz, 2H), 3.99 (s, 2H), 3.60 (s, 2H), 2.55-2.52 (m, 4H), 1.85-1.71
(m, 6H), 1.55-1.48 (m, 2H), 1.00 (t, J=7.4 Hz, 3H).
Preparation Example 2: the Compound of Formula II
2,4-dichloro-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[3,2-d]pyrimi-
dine
##STR00025##
[0069] In DMF (20.00 L) was dissolved
2,4-dichloro-5H-pyrrolo[3,2-d]pyrimidine (4.00 kg, 21.28 mol),
DIPEA (2.58 kg, 20.00 mol) was added in portions at room
temperature (25.degree. C.), and stirring was performed
subsequently for 30 min. The reaction liquid was cooled to
0.degree. C. with ice bath. Then SEM-Cl (4.00 kg, 24.00 mol) was
added dropwise slowly at the speed of 1-2 drop/s over 5 h. After
addition, the reaction was carried out at 0.degree. C. for 4 h with
stirring, and the reaction was monitored by HPLC until the reaction
was completed. The reaction liquid was quenched and diluted with 70
L of water, and extracted with ethyl acetate (15 L.times.3). The
combined organic phase was washed with 1 M hydrochloric acid
aqueous solution (5 L.times.2) and saturated brine (7 L.times.2)
successively. The solvent was removed by distillation under reduced
pressure to give the title compound (6.40 kg, 20.11 mol, yield
94.50%).
[0070] .sup.1H NMR (400 MHz, DMSO-d.sub.6) .delta. 8.24-8.35 (m,
1H), 6.70-6.85 (m, 1H), 5.77 (s, 2H), 3.45-3.57 (m, 2H), 0.74-0.86
(m, 2H), 0.00 (s, 9H).
2-chloro-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[3,2-d]pyrimidin-4-
-amine
##STR00026##
[0072] In isopropanol (1.60 L) was dissolved
2,4-dichloro-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[3,2-d]pyrimi-
dine (1.60 kg, 5.03 mol) in 10 L autoclave. Aqueous ammonia (4 L)
was added in one portion at room temperature (25.degree. C.). The
reaction mixture was stirred at 95.degree. C. for 7 h and monitored
by HPLC until the reaction was completed. The reaction liquid was
allowed to cool to room temperature, and filtered through a Buchner
funnel to give dark brown solid. The solid was slurried with ethyl
acetate/n-heptane (1/1, 5 L.times.2) and ethyl acetate (4 L)
successively to give the title compound as brown solid (1.25 kg,
4.18 mol, yield 83.1%).
[0073] .sup.1H NMR (400 MHz, DMSO-d.sub.6) .delta. 7.61-7.77 (m,
1H), 6.97-7.19 (m, 2H), 6.28-6.38 (m, 1H), 5.54-5.67 (m, 2H),
3.43-3.53 (m, 2H), 0.76-0.91 (m, 2H), 0.07 (s, 9H).
2-butoxy-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[3,2-d]pyrimidin-4-
-amine
##STR00027##
[0075] To n-BuOH (17.0 L) was slowly added sodium metal (525.05 g,
22.84 mol) in portions under nitrogen atmosphere. After addition,
the system was heated to 60.degree. C. and kept stirring at the
temperature until sodium metal was dissolved completely. The system
was cooled to 25.degree. C., and
2-chloro-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo
[3,2-d]pyrimidin-4-amine (1.95 kg, 6.53 mol) was added in portions.
After homogeneous mixing with stirring, the reactants were stirred
at 90.degree. C. for 8 h, and monitored by HPLC until the reaction
was completed. The reaction liquid was allowed to cool to
25.degree. C., poured into 30 L of saturated aqueous ammonium
chloride solution slowly, and extracted with ethyl acetate (15
L.times.3). The combined organic phase was washed with saturated
brine (20 L.times.2) and dried with anhydrous Na.sub.2SO.sub.4.
After filtration, solvent was removed by distillation under reduced
pressure and the residue was slurried in n-heptane (4 L).
Filtration was performed to give solid. The solid was then slurried
with ethyl acetate (5 L) to give the title compound as yellow-white
solid (1.53 kg, 4.55 mol, 69.7%).
[0076] .sup.1H NMR (400 MHz, DMSO-d.sub.6) .delta. 7.49-7.54 (m,
1H), 6.54-6.62 (m, 2H), 6.15-6.20 (m, 1H), 5.54 (s, 2H), 4.10-4.22
(m, 2H), 3.42-3.55 (m, 2H), 1.58-1.73 (m, 2H), 1.35-1.47 (m, 2H),
0.90-0.96 (m, 3H), 0.83-0.89 (m, 2H), 0.05 (s, 9H).
2-butoxy-5H-pyrrolo[3,2-d]pyrimidin-4-amine
##STR00028##
[0078] In TFA (5.50 L) was dissolved
2-butoxy-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[3,2-d]pyrimidin--
4-amine (1.10 kg, 3.27 mol). The reaction liquid was stirred at
25.degree. C. for 16 h, and monitored by HPLC until the reaction
was completed. TFA was removed by distillation under reduced
pressure. The residue was dissolved in methanol (1.2 L) and ice
water (1.2 L), concentrated aqueous ammonia was used under uniform
stirring to adjust pH to 12, and then stirring was performed for 2
h. Precipitate was precipitated out from solution continuously. The
filter cake was white solid after filtration, which was slurried
with 15% aqueous ammonia (1.2 L.times.3) and ethyl acetate (4 L)
successively to give the title compound as white solid (550.00 g,
2.67 mol, 81.7%).
[0079] .sup.1H NMR (400 MHz, methanol-d.sub.4) .delta. 7.37 (d,
J=2.89 Hz, 1H), 6.29 (d, J=3.01 Hz, 1H), 4.27 (t, J=6.53 Hz, 2H),
1.75 (d, J=7.91 Hz, 2H), 1.44-1.61 (m, 2H), 1.00 (t, J=7.40 Hz,
3H).
Examples of Pharmaceutical Activity
Toll-Like Receptor 7 and Toll-Like Receptor 8 In Vitro Receptor
Binding Activity Screen
Reagents:
[0080] HEK-blue hTLR7 cell and HEK-blue hTLR8 cell (available from
InvivoGen) DMEM medium heat inactivated fetal bovine serum Anti
Mycoplasma reagent Normocin.TM. bleomycin blasticidin
[0081] The structures of GS-9620 and R848 used are as follows,
wherein the preparation of GS-9620 could be referred to the process
disclosed in US20100143301; R848 was commercially available from
ABGENT (IMG-2208, specification: 0.5 mg).
##STR00029##
Scheme:
[0082] 1. Preparation of 96-well compound plate:
[0083] The compounds were gradient diluted with DMSO in 3-fold
using liquid work station POD starting at a concentration of 10
mmol/L and 10 points were diluted (2nd column to 11th column, and
each point was duplicated). At 12th column, 1 .mu.L of 5 mg/mL
positive compound R848 was added as positive control; and at 1st
column, 1 .mu.L of DMSO was added as negative control. Each well
contained 1 .mu.L of DMSO.
2. The cells in culture flask were collected and the cell density
was diluted to 250,000 cells/mL. 3. 200 .mu.L (50,000 cells/well)
of cell suspension was added into prepared compound plate and the
final concentration of DMSO in each well was 0.5%. 4. The culture
plates containing cells and the compounds were incubated in
CO.sub.2 incubator for 24 h at 37.degree. C., 5% CO.sub.2. 5. After
24 h incubation, 20 .mu.L of supernatant was removed from each well
to a 96-well transparent assay plate. To each well of the assay
plate was added 180 .mu.L of Quanti-Blue reagent and the plate was
incubated in an incubator at 37.degree. C., 5% CO.sub.2 for 1 h. 6.
After 1 h, the content of alkaline phosphatase in 20 .mu.L of
supernatant was determined using Microplate Reader OD650. 7.
EC.sub.50 of each compound was obtained with Prism software.
[0084] Results were shown in Table 1.
TABLE-US-00001 TABLE 1 Compound TLR7 EC.sub.50 Compound 1 B
Compound 2 C Compound 3 B Compound 4 B Compound 5 B Compound 6 C
Compound 7 C Compound 8 B Compound 9 B Compound 10 B Compound 11 B
Compound 12 B Compound 13 B Compound 14 B Compound 15 B Compound 16
B Note: 1 nM .ltoreq. A .ltoreq. 100 nM; 100 nM < B .ltoreq.
1000 nM; 1000 nM < C .ltoreq. 50 .mu.M.
[0085] Results of compound 1 and control sample Toll-like receptor
7 agonist GS-9620 were shown in Table 2.
TABLE-US-00002 TABLE 2 Samples (Title compound) TLR7 EC.sub.50 (nM)
TLR8 EC.sub.50 (nM) GS-9620 517 7867 Compound 1 160 11632
[0086] The compound according to the invention showed higher in
vitro receptor binding activity to Toll-like receptor 7 than the
control (Toll-like receptor 7 agonist GS-9620) and lower in vitro
receptor binding activity to Toll-like receptor 8 than the control
(Toll-like receptor 7 agonist GS-9620). The compound of the present
invention has distinct selectivity differences with respect to
different receptors, and the effect is superior over the prior
art.
* * * * *