U.S. patent application number 17/470723 was filed with the patent office on 2022-05-05 for methods of manufacturing treprostinil and treprostinil derivative prodrugs.
The applicant listed for this patent is Insmed Incorporated. Invention is credited to Donna M. KONICEK, Franziska LEIFER, Zhili LI, Vladimir MALININ, Walter PERKINS, Adam PLAUNT.
Application Number | 20220135513 17/470723 |
Document ID | / |
Family ID | 1000006081174 |
Filed Date | 2022-05-05 |
United States Patent
Application |
20220135513 |
Kind Code |
A1 |
MALININ; Vladimir ; et
al. |
May 5, 2022 |
METHODS OF MANUFACTURING TREPROSTINIL AND TREPROSTINIL DERIVATIVE
PRODRUGS
Abstract
Methods for making prodrugs of treprostinil and treprostinil
derivatives are provided. Specifically, methods are provided herein
for producing prostacyclin compounds comprising treprostinil
covalently linked to a linear C.sub.5-C.sub.18 alkyl, branched
C.sub.5-C.sub.18 alkyl, linear C.sub.2-C.sub.18 alkenyl, branched
C.sub.3-C.sub.18 alkenyl, aryl, aryl-C.sub.1-C.sub.18 alkyl or an
amino acid or a peptide (e.g., dipeptide, tripeptide,
tetrapeptide). The linkage, in one embodiment, is via an amide or
ester bond. Prostacyclin compounds provided herein can also include
at least one hydrogen atom substituted with at least one deuterium
atom. The compounds provided herein can be used to treat pulmonary
hypertension (e.g., pulmonary arterial hypertension) and
portopulmonary hypertension.
Inventors: |
MALININ; Vladimir;
(Bridgewater, NJ) ; PERKINS; Walter; (Bridgewater,
NJ) ; LEIFER; Franziska; (Bridgewater, NJ) ;
KONICEK; Donna M.; (Bridgewater, NJ) ; LI; Zhili;
(Bridgewater, NJ) ; PLAUNT; Adam; (Bridgewater,
NJ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Insmed Incorporated |
Bridgewater |
NJ |
US |
|
|
Family ID: |
1000006081174 |
Appl. No.: |
17/470723 |
Filed: |
September 9, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16417958 |
May 21, 2019 |
11148997 |
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17470723 |
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15527811 |
May 18, 2017 |
10343979 |
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PCT/US2015/061427 |
Nov 18, 2014 |
|
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16417958 |
|
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62081515 |
Nov 18, 2014 |
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Current U.S.
Class: |
560/56 |
Current CPC
Class: |
C07C 2601/18 20170501;
C07C 2602/24 20170501; C07C 67/08 20130101; C07C 231/02
20130101 |
International
Class: |
C07C 231/02 20060101
C07C231/02; C07C 67/08 20060101 C07C067/08 |
Claims
1.-31. (canceled)
32. A method for making a treprostinil prodrug having the following
formula: ##STR00112## comprising, mixing, in the presence of an
acid catalyst, a compound of Formula (A) with an alcohol of the
formula R.sub.2--OH, wherein R.sub.2 is a linear or branched
C.sub.5-C.sub.18 alkyl, a linear C.sub.2-C.sub.18 alkenyl or a
branched C.sub.3-C.sub.18 alkenyl, aryl, aryl-C.sub.1-C.sub.18
alkyl, an amino acid or a peptide, incubating the mixture for a
sufficient period of time to form the compound of Formula (A).
33.-53. (canceled)
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. application Ser.
No. 16/417,958, filed May 21, 2019, which is a continuation of U.S.
application Ser. No. 15/527,811, filed May 18, 2017, now U.S. Pat.
No. 10,343,979, which is a national phase of International
Application No. PCT/US2015/061427, filed Nov. 18, 2015, which
claims priority from U.S. Provisional Application Ser. No.
62/081,515, filed Nov. 18, 2014, the disclosure of each of which is
incorporated by reference herein in its entirety for all
purposes.
BACKGROUND OF THE INVENTION
[0002] Pulmonary hypertension (PH) is characterized by an
abnormally high blood pressure in the lung vasculature. It is a
progressive, lethal disease that leads to heart failure and can
occur in the pulmonary artery, pulmonary vein, or pulmonary
capillaries. Symptomatically patients experience shortness of
breath, dizziness, fainting, and other symptoms, all of which are
made worse by exertion. There are multiple causes, and can be of
unknown origin, idiopathic, and can lead to hypertension in other
systems, for example, portopulmonary hypertension in which patients
have both portal and pulmonary hypertension.
[0003] Pulmonary hypertension has been classified into five groups
by the World Health Organization (WHO). Group I is called pulmonary
arterial hypertension (PAH), and includes PAH that has no known
cause (idiopathic), inherited PAH (i.e., familial PAH or FPAH), PAH
that is caused by drugs or toxins, and PAH caused by conditions
such as connective tissue diseases, HIV infection, liver disease,
and congenital heart disease. Group II pulmonary hypertension is
characterized as pulmonary hypertension associated with left heart
disease. Group III pulmonary hypertension is characterized as PH
associated with lung diseases, such as chronic obstructive
pulmonary disease and interstitial lung diseases, as well as PH
associated with sleep-related breathing disorders (e.g., sleep
apnea). Group IV PH is PH due to chronic thrombotic and/or embolic
disease, e.g., PH caused by blood clots in the lungs or blood
clotting disorders. Group V includes PH caused by other disorders
or conditions, e.g., blood disorders (e.g., polycythemia vera,
essential thrombocythemia), systemic disorders (e.g., sarcoidosis,
vasculitis), metabolic disorders (e.g., thyroid disease, glycogen
storage disease).
[0004] Pulmonary arterial hypertension (PAH) afflicts approximately
200,000 people globally with approximately 30,000-40,000 of those
patients in the United States. PAH patients experience constriction
of pulmonary arteries which leads to high pulmonary arterial
pressures, making it difficult for the heart to pump blood to the
lungs. Patients suffer from shortness of breath and fatigue which
often severely limits the ability to perform physical activity.
[0005] The New York Heart Association (NYHA) has categorized PAH
patients into four functional classes, used to rate the severity of
the disease. Class I PAH patients as categorized by the NYHA, do
not have a limitation of physical activity, as ordinary physical
activity does not cause undue dyspnoea or fatigue, chest pain, or
near syncope. Treatment is not needed for class I PAH patients.
Class II PAH patients as categorized by the NYHA have a slight
limitation on physical activity. These patients are comfortable at
rest, but ordinary physical activity causes undue dyspnoea or
fatigue, chest pain or near syncope. Class III PAH patients as
categorized by the NYHA have a marked limitation of physical
activity. Although comfortable at rest, class III PAH patients
experience undue dyspnoea or fatigue, chest pain or near syncope as
a result of less than ordinary physical activity. Class IV PAH
patients as categorized by the NYHA are unable to carry out any
physical activity without symptoms. Class IV PAH patients might
experience dyspnoea and/or fatigue at rest, and discomfort is
increased by any physical activity. Signs of right heart failure
are often manifested by class IV PAH patients.
[0006] Patients with PAH are treated with an endothelin receptor
antagonist (ERA), phosphodiesterase type 5 (PDE-5) inhibitor, a
guanylate cyclase stimulator, a prostanoid (e.g., prostacyclin), or
a combination thereof. ERAs include abrisentan (Letairis.RTM.),
sitaxentan, bosentan (Tracleer.RTM.), and macitentan
(Opsumit.RTM.). PDE-5 inhibitors indicated for the treatment of PAH
include sildenafil (Revatio.RTM.), tadalafil (Adcirca.RTM.).
Prostanoids indicated for the treatment of PAH include iloprost,
epoprosentol and treprostinil (Remodulin.RTM., Tyvaso.RTM.). The
one approved guanylate cyclase stimulator is riociguat
(Adempas.RTM.). Additionally, patients are often treated with
combinations of the aforementioned compounds.
[0007] Portopulmonary hypertension is defined by the coexistence of
portal and pulmonary hypertension, and is a serious complication of
liver disease. The diagnosis of portopulmonary hypertension is
based on hemodynamic criteria: (1) portal hypertension and/or liver
disease (clinical diagnosis-ascites/varices/splenomegaly), (2) mean
pulmonary artery pressure >25 mmHg at rest, (3) pulmonary
vascular resistance >240 dynes s/cm.sup.5, (4) pulmonary artery
occlusion pressure <15 mmHg or transpulmonary gradient >12
mmHg. PPH is a serious complication of liver disease, and is
present in 0.25 to 4% of patients suffering from cirrhosis. Today,
PPH is comorbid in 4-6% of those referred for a liver
transplant.
[0008] Despite there being treatments for PAH and PPH, the current
prostacyclin therapies are associated with severe toxicity and
tolerability issues, as well as the requirement for inconvenient
dosing schedules. The present invention overcomes addresses these
factors by providing compounds and that provide for less toxicity,
better tolerability and more convenient dosing schedules, and
methods for manufacturing the same.
SUMMARY OF THE INVENTION
[0009] Methods for the manufacture of treprostinil prodrugs and
treprostinil derivative prodrugs are provided herein, e.g.,
compounds of the Formulae (I), (II) or (III). The treprostinil or
treprostinil derivative prodrug, in one embodiment, comprises an
ester or amide linkage to the prodrug moiety.
[0010] One aspect of the invention relates to the synthesis of a
carboxylic acid derivative of treprostinil. In one embodiment, a
treprostinil ester derivative of the formula
##STR00001##
is esterified by mixing the appropriate alcohol (i.e., R.sub.2--OH
where the R.sub.2 is a linear or branched C.sub.5-C.sub.18 alkyl, a
linear C.sub.2-C.sub.18 alkenyl or a branched C.sub.3-C.sub.18
alkenyl) with treprostinil or a compound of the formula
##STR00002##
in the presence of an acid catalyst. The acid catalyst in one
embodiment is a resin or in some other solid form. The acid
catalyst in one embodiment is sulfuric acid or sulfonic acid. Other
acid catalysts (in solid, e.g., a resin, or liquid form) include
but are not limited to hydrofluoric acid, phosphoric acid,
toluenesulfonic acid, polystyrene solfonate, hyeteropoly acid,
zeolites, metal oxides, and graphene oxygene
[0011] In some embodiments, the treprostinil or treprostinil
compound of the formula
##STR00003##
(where R.sub.3, R.sub.4 and n are defined above) and/or alcohol
R.sub.2--OH is dissolved in a solvent prior to the esterification
reaction.
[0012] In another embodiment, the Mitsunobu reaction can be used,
where a mixture of triphenylphosphine (PPh.sub.3) and diisopropyl
azodicarboxylate (DIAD or its diethyl analogue, DEAD) convert an
alcohol and carboxylic acid to the ester to form one of the
carboxylic acid ester prodrugs provided herein.
[0013] In yet another embodiment, N, N'-dicyclohexylcarbodiimide
(DCC) or N, N'-diisopropylcarbodiimide (DIC) is used in combination
with 4-dimethylaminopyridine (DMAP) in an esterification reaction
(sometimes referred to as Steglich esterification).
[0014] Treprostinil amide derivatives (e.g., of the formula:
##STR00004##
can be manufactured according to well known protocols of amide
functionalization of a carboxylic acid group. For example,
treprostinil (or a compound of the formula
##STR00005##
(for example, dissolved in dioxane) is combined with HATU or PyBOP
and alkylamine R.sub.2--NH.sub.2 R.sub.2, R.sub.3, R.sub.4 and n
are defined herein.
[0015] The methods provided herein in one embodiment, are used to
manufacture a prostacyclin compound of Formula (I), or a
pharmaceutically acceptable salt:
##STR00006##
[0016] wherein R.sub.1 is NH, O or S; R.sub.2 is H, a linear
C.sub.5-C.sub.18 alkyl, branched C.sub.5-C.sub.18 alkyl, linear
C.sub.2-C.sub.18 alkenyl, branched C.sub.3-C.sub.18 alkenyl, aryl;
aryl-C.sub.1-C.sub.18 alkyl; an amino acid or a peptide; R.sub.3 is
H, OH, O-alkyl or O-alkenyl; R.sub.4 is an optionally substituted
linear or branched C.sub.1-C.sub.15 alkyl, or an optionally
substituted linear or branched C.sub.2-C.sub.15 alkenyl; and n is
an integer from 0 to 5, with the proviso that the prostacyclin
compound is not treprostinil.
[0017] In another embodiment, a method provided herein is used to
manufacture a prostacyclin compound of Formula (II), or a
pharmaceutically acceptable salt:
##STR00007##
[0018] wherein R.sub.1 is NH, O or S; R.sub.2 is a linear or
branched C.sub.5-C.sub.18 alkyl, a linear C.sub.2-C.sub.18 alkenyl
or a branched C.sub.3-C.sub.18 alkenyl, aryl, aryl-C.sub.1-C.sub.18
alkyl, an amino acid or a peptide; and n is an integer from 0 to
5.
[0019] In one embodiment, a compound of Formula (I) and/or (II) is
manufactured by a method described herein, wherein one or more
hydrogen atoms is substituted with a deuterium. Accordingly, in one
embodiment, the present invention relates to an isotopologue of
Formula (I) and/or (II), substituted with one or more deuterium
atoms. The isotopologue of Formula (I) and/or (II) may be used to
accurately determine the concentration of compounds of Formula (I)
and/or (II) in biological fluids and to determine metabolic
patterns of compounds of Formula (I) and/or (II) and its
isotopologues.
[0020] Yet another embodiment of the invention relates to a method
for manufacturing the prostacyclin compound of Formula (III), or a
pharmaceutically acceptable salt:
##STR00008##
[0021] wherein R.sub.1 and R.sub.2 are defined above, and
[0022] R.sub.5 and R.sub.6 are independently selected from H,
optionally substituted linear or branched C.sub.1-C.sub.15 alkyl,
optionally substituted linear or branched C.sub.2-C.sub.15 alkenyl,
(C.dbd.O)-optionally substituted linear or branched
C.sub.1-C.sub.15 alkyl, or (C.dbd.O)-optionally substituted linear
or branched C.sub.2-C.sub.15 alkenyl, with the proviso that the
prostacyclin compound of Formula (III) is not treprostinil.
BRIEF DESCRIPTION OF THE FIGURES
[0023] FIG. 1 is an esterification scheme for an alkyl ester-TR
prodrug compound provided herein.
[0024] FIG. 2 is a general scheme for synthesis of acylated
treprostinil derivative prodrugs.
DETAILED DESCRIPTION OF THE INVENTION
[0025] The term "alkyl" as used herein refers to both a straight
chain alkyl, wherein alkyl chain length is indicated by a range of
numbers, and a branched alkyl, wherein a branching point in the
chain exists, and the total number of carbons in the chain is
indicated by a range of numbers. In exemplary embodiments, "alkyl"
refers to an alkyl chain as defined above containing 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16 carbons (i.e., C.sub.6-C.sub.16
alkyl).
[0026] The term "alkenyl" as used herein refers to a carbon chain
containing one or more carbon-carbon double bonds.
[0027] The term "aryl" as used herein refers to a cyclic
hydrocarbon, where the ring is characterized by delocalized .pi.
electrons (aromaticity) shared among the ring members, and wherein
the number of ring atoms is indicated by a range of numbers. In
exemplary embodiments, "aryl" refers to a cyclic hydrocarbon as
described above containing 6, 7, 8, 9, or 10 ring atoms (i.e.,
C.sub.6-C.sub.10 aryl). Examples of an aryl group include, but are
not limited to, benzene, naphthalene, tetralin, indene, and
indane.
[0028] The term "alkoxy" as used herein refers to --O-(alkyl),
wherein "alkyl" is as defined above.
[0029] The term "substituted" in connection with a moiety as used
herein refers to a further substituent which is attached to the
moiety at any acceptable location on the moiety. Unless otherwise
indicated, moieties can bond through a carbon, nitrogen, oxygen,
sulfur, or any other acceptable atom.
[0030] The term "amino acid" refers to both natural (genetically
encoded) and non-natural (non-genetically encoded) amino acids, and
moieties thereof. Of the twenty natural amino acids, 19 have the
general structure:
##STR00009##
where R is the amino acid sidechain. The 20.sup.th amino acid,
proline, is also within the scope of the present invention, and has
the following structure:
##STR00010##
Of the twenty natural amino acids, all but glycine is chiral, and
both the D- and L-amino acid isomers, as well as mixtures thereof,
are amenable for use with the prostacyclin compounds described
herein. It is also noted that an amino acid moiety is encompassed
by the term "amino acid." For example, the amino acid moieties
##STR00011##
are encompassed by the term "amino acid."
[0031] Examples of non-natural amino acids amenable for use with
the present invention include .beta.-alanine (.beta.-Ala);
2,3-diaminopropionic acid (Dpr); nipecotic acid (Nip); pipecolic
acid (Pip); ornithine (Om); citrulline (Cit); t-butylalanine
(t-BuA); 2-tbutylglycine (t-BuG); N-methylisoleucine (MeIle);
phenylglycine (PhG); cyclohexylalanine (ChA); norleucine (Nle);
naphthylalanine (Nal); 4-chlorophenylalanine (Phe(4-Cl));
2-fluorophenylalanine (Phe(2-F)); 3-fluorophen ylalanine
(Phe(3-F)); 4-fluorophenylalanine (Phe(4-F)); penicillamine (Pen);
1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic);
.beta.-2-thienylalanine (Thi); methionine sulfoxide (MSO);
homoarginine (hArg); N-acetyllysine (AcLys); 2,4-diaminobutyric
acid (Dbu); 2,3-diaminobutyric acid (Dab); p-aminophenylalanine
(Phe (pNH.sub.2)); N-methyl valine (MeVal); homocysteine (hCys),
homophenylalanine (hPhe); homoserine (hSer); hydroxyproline (Hyp);
homoproline (hPro); and the corresponding D-enantiomer of each of
the foregoing. Other non-genetically encoded amino acid residues
include 3-aminopropionic acid; 4-aminobutyric acid; isonipecotic
acid (Inp); aza-pipecolic acid (azPip); aza-proline (azPro);
.alpha.-aminoisobutyric acid (Aib); .epsilon.-aminohexanoic acid
(Aha); .delta.-aminovaleric acid (Ava); N-methylglycine
(MeGly).
[0032] A "peptide" is a polymer of amino acids (or moieties
thereof) linked by a peptide bond. Peptides for use with the
present invention, comprise from about two to about fifteen amino
acids, for example, two, three, four, five, six, seven, eight, nine
or ten amino acids (or moieties thereof).
[0033] The term "salt" or "salts" as used herein encompasses
pharmaceutically acceptable salts commonly used to form alkali
metal salts of free acids and to form addition salts of free bases.
The nature of the salt is not critical, provided that it is
pharmaceutically acceptable. Suitable pharmaceutically acceptable
acid addition salts may be prepared from an inorganic acid or from
an organic acid. Exemplary pharmaceutical salts are disclosed in
Stahl, P. H., Wermuth, C. G., Eds. Handbook of Pharmaceutical
Salts: Properties, Selection and Use; Verlag Helvetica Chimica
Acta/Wiley-VCH: Zurich, 2002, the contents of which are hereby
incorporated by reference in their entirety. Specific non-limiting
examples of inorganic acids are hydrochloric, hydrobromic,
hydroiodic, nitric, carbonic, sulfuric and phosphoric acid.
Appropriate organic acids include, without limitation, aliphatic,
cycloaliphatic, aromatic, arylaliphatic, and heterocyclyl
containing carboxylic acids and sulfonic acids, for example formic,
acetic, propionic, succinic, glycolic, gluconic, lactic, malic,
tartaric, citric, ascorbic, glucuronic, maleic, fumaric, pyruvic,
aspartic, glutamic, benzoic, anthranilic, mesylic, stearic,
salicylic, p-hydroxybenzoic, phenylacetic, mandelic, embonic
(pamoic), methanesulfonic, ethanesulfonic, benzenesulfonic,
pantothenic, toluenesulfonic, 2-hydroxyethanesulfonic, sulfanilic,
cyclohexylaminosulfonic, algenic, 3-hydroxybutyric, galactaric or
galacturonic acid. Suitable pharmaceutically acceptable salts of
free acid-containing compounds disclosed herein include, without
limitation, metallic salts and organic salts. Exemplary metallic
salts include, but are not limited to, appropriate alkali metal
(group Ia) salts, alkaline earth metal (group IIa) salts, and other
physiological acceptable metals. Such salts can be made from
aluminum, calcium, lithium, magnesium, potassium, sodium and zinc.
Exemplary organic salts can be made from primary amines, secondary
amines, tertiary amines and quaternary ammonium salts, for example,
tromethamine, diethylamine, tetra-N-methyl ammonium,
N,N'-dibenzylethylenediamine, chloroprocaine, choline,
diethanolamine, ethylenediamine, meglumine (N-methylglucamine) and
procaine.
[0034] Methods are provided herein for the synthesis of
treprostinil prodrugs, as well as treprostinil derivative prodrugs,
for example prodrugs of Formulae (I), (II) and (III). The prodrugs
find utility in the treatment of pulmonary hypertension, for
example, pulmonary arterial hypertension and portopulmonary
hypertension, as well as other indications, as described in U.S.
Patent Application Publication No. 2015/0148414, published May 28,
2015, the disclosure of which is incorporated by reference in its
entirety for all purposes. For example, the treprostinil derivative
prodrug or treprostinil prodrug, or a composition comprising the
same, is effective when employed in a once-daily, twice-daily or
three-times daily dosing regimen, for example, for the treatment of
pulmonary arterial hypertension or portopulmonary hypertension in a
patient in need thereof. The prostacyclin compound provided herein,
in one embodiment, can be administered less frequently than
treprostinil, with equal or greater efficacy. Moreover, in one
embodiment, the side effect profile of the compounds provided
herein is less deleterious than the side effect profile resulting
from treprostinil administration.
[0035] One aspect of the invention relates to the synthesis of a
carboxylic acid derivative of treprostinil. In one embodiment, a
treprostinil ester derivative of the formula
##STR00012##
is esterified by mixing the appropriate alcohol (i.e., R.sub.2--OH
where the R.sub.2 is a linear or branched C.sub.5-C.sub.18 alkyl, a
linear C.sub.2-C.sub.18 alkenyl or a branched C.sub.3-C.sub.18
alkenyl) with treprostinil or a compound of the formula
##STR00013##
in the presence of an acid catalyst. As provided herein, R.sub.3 is
H, OH, optionally substituted linear or branched C.sub.1-C.sub.15
alkyoxy, O-optionally substituted linear or branched
C.sub.2-C.sub.15 alkenyl, O--(C.dbd.O)-optionally substituted
linear or branched C.sub.1-C.sub.15 alkyl, or
O--(C.dbd.O)-optionally substituted linear or branched
C.sub.2-C.sub.15 alkenyl; R.sub.4 is an optionally substituted
linear or branched C.sub.1-C.sub.15 alkyl, or an optionally
substituted linear or branched C.sub.2-C.sub.15 alkenyl; and n is
an integer from 0 to 5. It will be appreciated by one of ordinary
skill in the art that the purity of the final product will depend
in part on the purity of the reagents employed in the
esterification reaction, and/or the cleanup procedure after the
reaction has completed. For example, a high purity alcohol will
give a higher purity treprostinil ester derivative than a lower
purity alcohol. Similarly, a higher purity product is obtained
through clean-up procedures such as HPLC, diafiltration, etc.
[0036] The acid catalyst in one embodiment is a resin or in some
other solid form. However, in other embodiment, the acid catalyst
is in liquid form. The acid catalyst in one embodiment is sulfuric
acid or sulfonic acid. Other acid catalysts (in solid, e.g., a
resin, or liquid form) include but are not limited to hydrofluoric
acid, phosphoric acid, toluenesulfonic acid, polystyrene solfonate,
hyeteropoly acid, zeolites, metal oxides, and graphene oxygene.
[0037] Acid catalyst resins, e.g., sulfonic acid resin catalysts
are available commercially, e.g., from Sigma-Aldrich, under the
trade name AMBERLYST. Other resins are available commercially,
e.g., from Purolite.RTM., and are amenable for use with the methods
described herein.
[0038] In some embodiments, the treprostinil or the treprostinil
compound of the formula
##STR00014##
(where R.sub.3, R.sub.4 and n are defined above) and/or alcohol
R.sub.2--OH is dissolved in a solvent prior to the esterification
reaction. For example, in one embodiment, where treprostinil is
esterified with an alkyl group having 12 carbon atoms or more,
treprostinil is first dissolved in a solvent such as dioxane prior
to the esterification reaction. Other solvents besides dioxane, or
in combination with dioxane can also be used. For example,
acetonitrile (MeCN), N,N'-dimethylformamide (DMF), dichloromethane
(DCM), or a combination thereof can be used. Various examples of
solvents are provided in Table 1 below.
TABLE-US-00001 TABLE 1 Solvents amenable for use in esterification
reactions. Dioxane Dioxane (2 mL/100 .mu.mol TRP) Dioxane (1 mL/100
.mu.mol TRP) DMF DCM MeCN 1:1 Dioxane:MeCN DMF/DCM 10% DMF/DCM 20%
DMF/DCM
[0039] Carboxylic acid esterification reactions other than the ones
described above are known to those of ordinary skill in the art and
are amenable for use in manufacturing the treprostinil alkyl esters
described herein. For example, the Mitsunobu reaction can be used,
where a mixture of triphenylphosphine (PPh.sub.3) and diisopropyl
azodicarboxylate (DIAD or its diethyl analogue, DEAD) convert an
alcohol and carboxylic acid to the ester. In this reaction, the
DIAD is reduced as it serves as the hydrogen acceptor, and the
PPh.sub.3 is oxidized to OPPh.sub.3.
[0040] In yet another embodiment, N, N'-dicyclohexylcarbodiimide
(DCC) or N, N'-diisopropylcarbodiimide (DIC) is used in combination
with 4-dimethylaminopyridine (DMAP) (additive) in an esterification
reaction (sometimes referred to as Steglich esterification). In
this reaction, DCC or DIC and the carboxylic acid (treprostinil or
its non-esterified derivative) are able to form an O-acylisourea
activated carboxylic acid intermediate. The alcohol is added to the
activated compound to form the stable dicyclohexylurea and the
ester. In one embodiment, the treprostinil or its non-esterified
derivative is first dissolved in solvent, e.g., one of the solvents
described above, prior to performing the Steglich
esterification.
[0041] Other esterification reactions can be employed. For example,
1-[Bis (dimethylamino) methylene]-1H-1,2,3-triazolo[4,5-b]
pyridinium 3-oxide hexafluorophosphate (HATU) or
benzotriazol-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate
(PyBOP) can be used as a coupling reagent. These reagents can be
used with or without an additive to facilitate the coupling. For
example, triethylamine (TEA) can be used in some embodiments in
conjunction with either HATU or PyBOP coupling reagents to form a
treprostinil alkyl ester. As with the other esterification
reactions described herein, the treprostinil or non-esterified
treprostinil derivative can first be dissolved in solvent prior to
performing the esterification reaction.
[0042] In yet another embodiment, an esterification of treprostinil
or a treprostinil derivative proceeds through steps 1 through 5 of
the reaction scheme set forth in Example 3 of PCT Publication No.
WO 2011/153363, incorporated by reference herein in its entirety
for all purposes.
[0043] Treprostinil amide derivatives (e.g., of the formula:
##STR00015##
can be manufactured according to protocols of amide
functionalization of a carboxylic acid group. For example,
treprostinil (or a compound of the formula
##STR00016##
(for example, dissolved in dioxane) is combined with HATU or PyBOP
and alkylamine R.sub.2--NH.sub.2 R.sub.2, R.sub.3, R.sub.4 and n
are defined above.
[0044] Other reaction conditions for forming treprostinil amide
derivatives with alkylamine R.sub.2--NH.sub.2, are provided below
in Table 2.
TABLE-US-00002 TABLE 2 Coupling Entry Solvent Time Reagent Additive
Base Amine (Equiv) Amine Delay 1 10% DMF/DCM 68 h DCC DMAP -- 5.0
-- 2 Dioxane 68 h DSC -- -- 5.0 30 min 3 Dioxane 92 h DSC -- -- 5.0
68 h 4 Dioxane 68 h -- -- -- 5.0 -- 5 Dioxane 92 h DSC -- DIPEA 5.0
68 h 6 10% DMF/DCM 68 h MIBA Mol. -- 1.0 -- Sieve 7 10% DMF/DCM 68
h DSC -- -- 5.0 30 min 8 Dioxane 18 h DCC -- -- 5.0 -- 9 Dioxane 48
h DSC -- DIPEA 5.0 24 h 10 10% DMF/DCM 18 h DCC -- -- 5.0 -- 11 DMF
18 h DCC -- -- 5.0 -- 12 DMF 48 h DSC -- DIPEA 5.0 24 h 13 Dioxane
48 h DCC DMAP -- 10.0 -- 14 Dioxane 48 h DCC -- -- 10.0 -- 15
Dioxane 115 h DSC -- DIPEA 5.0 91 h 16 Dioxane 18 h DSC DMAP DIPEA
5.0 150 m 17 Dioxane 115 h DSC DMAP DIPEA 5.0 91 h 18 Dioxane 86 h
DSC -- DIPEA 7.5 68 h 19 DMF 1 h HATU -- DIPEA 1.2 -- 20 DMF 1 h
PyBOP -- DIPEA 1.2 -- 21 1:2 1 h PyBOP -- DIPEA 1.2 -- Dioxane:MeCN
22 Dioxane 18 h DCC HOBt DIPEA 1.2 -- 23 Dioxane 18 h DIC HOBt
DIPEA 1.2 -- 24 Dioxane 18 h EDC HOBt DIPEA 1.2 -- 25 Dioxane 48 h
DCC NHS DIPEA 1.2 24 h 26 Dioxane 48 h DIC NHS DIPEA 1.2 24 h 27
Dioxane 48 h EDC NHS DIPEA 1.2 24 h 28 Dioxane 48 h DCC PfpOH DIPEA
1.2 24 h 29 Dioxane 48 h DIC PfpOH DIPEA 1.2 24 h 30 Dioxane 48 h
EDC PfpOH DIPEA 1.2 24 h DCC = N,N'-Dicyclohexylcarbodiimide DIC =
N,N'-Diisopropylcarbodiimide DSC = N,N'-Disuccinimidyl carbonate
DIPEA = N,N-Diisopropylethylamine DMF = N,N'-dimethylformamide EDC
= N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride HATU
=
1-[Bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium
3-oxid hexafluorophosphate HOBt = 1-Hydroxybenzotriazole hydrate
MIBA = 5-methoxy-2-iodophenyiboronic acid PyBOP =
benzotriazol-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate
PfpOH = 2,2,3,3,3-Pentafluoro-1-propanol
[0045] In one aspect of the invention described herein, a
prostacyclin compound of Formula (I), or a pharmaceutically
acceptable salt thereof, is manufactured by a method described
herein:
##STR00017##
[0046] wherein R.sub.1 is NH, O or S;
[0047] R.sub.2 is H, a linear C.sub.5-C.sub.18 alkyl, branched
C.sub.5-C.sub.18 alkyl, linear C.sub.2-C.sub.18 alkenyl, branched
C.sub.3-C.sub.18 alkenyl, aryl, aryl-C.sub.1-C.sub.18 alkyl; an
amino acid or a peptide;
[0048] R.sub.3 is H, OH, optionally substituted linear or branched
C.sub.1-C.sub.15 alkyoxy, O-optionally substituted linear or
branched C.sub.2-C.sub.15 alkenyl, O--(C.dbd.O)-optionally
substituted linear or branched C.sub.1-C.sub.15 alkyl, or
O--(C.dbd.O)-optionally substituted linear or branched
C.sub.2-C.sub.15 alkenyl;
[0049] R.sub.4 is an optionally substituted linear or branched
C.sub.1-C.sub.15 alkyl, or an optionally substituted linear or
branched C.sub.2-C.sub.15 alkenyl; and n is an integer from 0 to 5,
with the proviso that the prostacyclin compound of Formula (I) is
not treprostinil.
[0050] In a further embodiment, a prostacyclin compound of Formula
(I) is manufactured, wherein R.sub.3 is OH and n is 0 or 1. In even
a further embodiment, R.sub.4 is an optionally substituted linear
or branched C.sub.1-C.sub.15 alkyl. In even a further embodiment,
R.sub.1 is NH or O.
[0051] In one embodiment, a prostacyclin compound of Formula (I) is
manufactured, wherein R.sub.1 is NH, O or S; R.sub.2 is a linear
C.sub.5-C.sub.18 alkyl, branched C.sub.5-C.sub.18 alkyl, linear
C.sub.2-C.sub.18 alkenyl, branched C.sub.3-C.sub.18 alkenyl;
R.sub.3 is H, OH or O-alkyl; R.sub.4 is an optionally substituted
linear or branched C.sub.1-C.sub.15 alkyl, or an optionally
substituted linear or branched C.sub.2-C.sub.15 alkenyl; and n is
an integer from 0 to 5. In even a further embodiment, R.sub.1 is NH
or O and R.sub.2 is a linear C.sub.5-C.sub.18 alkyl or a branched
C.sub.5-C.sub.18 alkyl.
[0052] In one embodiment, R.sub.2 is aryl or aryl-C.sub.1-C.sub.18
alkyl; R.sub.3 is OH and n is 0 or 1. In even a further embodiment,
R.sub.4 is an optionally substituted linear or branched
C.sub.1-C.sub.15 alkyl.
[0053] In one embodiment, the present invention provides a method
for manufacturing a prostacyclin compound of Formula (I), wherein
the compound is a compound of one of Formulae (Ia), (Ib), (Ic) or
(Id), or a pharmaceutically acceptable salt thereof:
##STR00018##
[0054] wherein, R.sub.2 is H, a linear or branched C.sub.5-C.sub.18
alkyl, linear C.sub.2-C.sub.18 alkenyl, or a branched
C.sub.3-C.sub.18 alkenyl;
[0055] R.sub.3 is H, OH, optionally substituted linear or branched
C.sub.1-C.sub.15 alkyoxy, O-optionally substituted linear or
branched C.sub.2-C.sub.15 alkenyl, --O(C.dbd.O)-optionally
substituted linear or branched C.sub.1-C.sub.15 alkyl, or
--O(C.dbd.O)-optionally substituted linear or branched
C.sub.2-C.sub.15 alkenyl; and
[0056] R.sub.4 is
##STR00019##
an optionally substituted linear or branched C.sub.1-C.sub.15
alkyl, or an optionally substituted linear or branched
C.sub.2-C.sub.15 alkenyl, where R.sub.5 is H, optionally
substituted linear or branched C.sub.1-C.sub.18 alkyl, optionally
substituted linear or branched C.sub.2-C.sub.15 alkenyl,
(C.dbd.O)-optionally substituted linear or branched
C.sub.1-C.sub.15 alkyl, or (C.dbd.O)-optionally substituted linear
or branched C.sub.2-C.sub.15 alkenyl. In a further embodiment,
R.sub.4 is
##STR00020##
with the proviso that the compound is not treprostinil, i.e.,
R.sub.2 and R.sub.5 cannot both be H.
[0057] In one embodiment of Formula (Ia), Formula (Ib), Formula
(Ic) and Formula (Id), R.sub.2 is a linear or branched
C.sub.5-C.sub.18 alkyl. In even a further embodiment, R.sub.2
is
##STR00021##
where m1 and m2 are each independently an integer selected from 1
to 9 and each occurrence of R' is independently H, a linear or
branched C.sub.1-C.sub.8 alkyl, or a linear or branched
C.sub.1-C.sub.8 alkenyl. In even a further embodiment, R.sub.2
is
##STR00022##
and m1 and m2 are both 4. In another embodiment, R.sub.2 is
##STR00023##
and m1 is 3 and m2 is 4, or m1 is 2 and m2 is 3.
[0058] When m1 and/or m2 is an integer from 2-9, the m1/m2 at the
end of the carbon chain is CH.sub.3, while the remaining m1/m2
groups are CH.sub.2.
[0059] In one embodiment of Formula (Ia), Formula (Ib), Formula
(Ic) and Formula (Id), R.sub.2 is
##STR00024##
In a further embodiment, R.sub.3 is OH and R.sub.4 is
##STR00025##
where R.sub.5 is H, optionally substituted linear or branched
C.sub.1-C.sub.15 alkyl, optionally substituted linear or branched
C.sub.2-C.sub.15 alkenyl, (C.dbd.O)-optionally substituted linear
or branched C.sub.1-C.sub.15 alkyl, or (C.dbd.O)-optionally
substituted linear or branched C.sub.2-C.sub.15 alkenyl.
[0060] In one embodiment of Formulae (Ia), (Ib), (Ic) or (Id),
R.sub.2 is H, R.sub.3 is OH and R.sub.4 is
##STR00026##
and R.sub.5 is
##STR00027##
[0061] where m1 and m2 are each independently an integer selected
from 1 to 9 and each occurrence of R' is independently H, a linear
or branched C.sub.1-C.sub.8 alkyl, or a linear or branched
C.sub.1-C.sub.8 alkenyl. When m1 and/or m2 is an integer from 2-9,
the m1/m2 at the end of the carbon chain is CH.sub.3, while the
remaining m1/m2 groups are CH.sub.2.
[0062] In another embodiment, a method for manufacturing a
prostacyclin compound of one of Formula (Ia), (Ib), (Ic) or (Id) is
provided wherein R.sub.3 is OH, as provided in one of Formulae
(Ia'), (Ib'), (Ic') or (Id'):
##STR00028##
wherein, R.sub.2 is H, a linear or branched C.sub.5-C.sub.18 alkyl,
or a linear or branched C.sub.5-C.sub.18 alkenyl; and R.sub.4
is
##STR00029##
an optionally substituted linear or branched C.sub.1-C.sub.15
alkyl, or an optionally substituted linear or branched
C.sub.2-C.sub.15 alkenyl, wherein R5 is H, optionally substituted
linear or branched C.sub.1-C.sub.15 alkyl, optionally substituted
linear or branched C.sub.2-C.sub.15 alkenyl, (C.dbd.O)-optionally
substituted linear or branched C.sub.1-C.sub.15 alkyl, or
(C.dbd.O)-optionally substituted linear or branched
C.sub.2-C.sub.15 alkenyl, with the proviso that R.sub.2 and R.sub.5
are not both H. In one embodiment of Formula (Ia'), Formula (Ib'),
Formula (Ic') and Formula (Id'), R.sub.4 is
##STR00030##
and R.sub.2 is
##STR00031##
[0063] or R.sub.5 is
##STR00032##
[0064] where m1 and m2 are each independently an integer selected
from 1 to 9 and each occurrence of R' is independently H, a linear
or branched C.sub.1-C.sub.8 alkyl, or a linear or branched
C.sub.1-C.sub.8 alkenyl. In even a further embodiment, R.sub.2
is
##STR00033##
[0065] Yet another embodiment of the invention relates to a method
for manufacturing a prostacyclin compound of one of Formula (Ia''),
(Ib''), (Ic'') or (Id''), or a pharmaceutically acceptable salt
thereof:
##STR00034##
wherein,
[0066] R.sub.2 is H, a linear or branched C.sub.5-C.sub.18 alkyl,
linear C.sub.2-C.sub.18 alkenyl, branched C.sub.3-C.sub.18 alkenyl,
aryl, aryl-C.sub.1-C.sub.18 alkyl; an amino acid or a peptide;
and
[0067] R.sub.3 is H, OH, optionally substituted linear or branched
C.sub.1-C.sub.15 alkyoxy, O-optionally substituted linear or
branched C.sub.2-C.sub.15 alkenyl, O--(C.dbd.O)-optionally
substituted linear or branched C.sub.1-C.sub.15 alkyl, or
O--(C.dbd.O)-optionally substituted linear or branched
C.sub.2-C.sub.15 alkenyl; and
[0068] R.sub.5 is H, optionally substituted linear or branched
C.sub.1-C.sub.15 alkyl, optionally substituted linear or branched
C.sub.2-C.sub.15 alkenyl, (C.dbd.O)-optionally substituted linear
or branched C.sub.1-C.sub.15 alkyl, or (C.dbd.O)-optionally
substituted linear or branched C.sub.2-C.sub.15 alkenyl, with the
proviso that R.sub.2 and R.sub.5 are not both H. In a further
embodiment, R.sub.3 is OH and R.sub.2 is 5-nonanyl, 4-heptyl,
4-octyl, 3-octyl, 2-dimethyl-1-propyl, 3,3-dimethyl-1-butyl,
2-ethyl-1-butyl, 3-pentyl, pentyl, hexyl, heptyl, octyl, nonyl,
decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl,
hexadecyl, heptadecyl or octadecyl. In even a further embodiment,
R.sub.2 is decyl, undecyl, dodecyl, tridecyl, tetradecyl,
pentadecyl, hexadecyl, heptadecyl or octadecyl. In even a further
embodiment, R.sub.2 is a linear alkyl.
[0069] One embodiment of the present invention is directed to a
method for manufacturing a compound of Formula (Ic), (Ic') and
(Ic''). In a further embodiment, R.sub.2 is a linear
C.sub.5-C.sub.18 alkyl or a branched C.sub.5-C.sub.18 alkyl. In
even a further embodiment, R.sub.2 is a linear C.sub.6-C.sub.18
alkyl or a branched C.sub.6-C.sub.18 alkyl. In yet a further
embodiment, R.sub.2 is a linear C.sub.6-C.sub.14 alkyl, e.g., a
linear C.sub.6 alkyl, C.sub.8 alkyl, C.sub.10 alkyl, C.sub.12 alkyl
or C.sub.14 alkyl.
[0070] In one embodiment, a compound of Formula (Ic'') is provided
wherein R.sub.2 is a linear C.sub.5-C.sub.18 alkyl; R.sub.3 is OH
and R.sub.5 is H. In another embodiment, a compound of Formula
(Ic'') is provided wherein R.sub.2 is a linear C.sub.6-C.sub.18
alkyl; R.sub.3 is OH and R.sub.5 is H. In yet embodiment, a
compound of Formula (Ic'') is provided wherein R.sub.2 is a linear
C.sub.6-C.sub.16 alkyl; R.sub.3 is OH and R.sub.5 is H. In even
another embodiment, a compound of Formula (Ic'') is provided
wherein R.sub.2 is a linear C.sub.8-C.sub.14 alkyl; R.sub.3 is OH
and R.sub.5 is OH.
[0071] In one embodiment, a method for manufacturing a prostacyclin
compound of Formula (Ic'') is provided wherein R.sub.2 is a linear
C.sub.5-C.sub.18 alkyl; R.sub.3 is OH and R.sub.5 is H. In another
embodiment, a compound of Formula (Ic'') is provided wherein
R.sub.2 is a branched C.sub.6-C.sub.18 alkyl; R.sub.3 is OH and
R.sub.5 is H. In yet embodiment, a compound of Formula (Ic'') is
provided wherein R.sub.2 is a branched C.sub.6-C.sub.16 alkyl;
R.sub.3 is OH and R.sub.5 is H. In even another embodiment, a
compound of Formula (Ic'') is provided wherein R.sub.2 is a
branched C.sub.5-C.sub.14 alkyl; R.sub.3 is OH and R.sub.5 is
H.
[0072] In yet another embodiment a method for manufacturing a
prostacyclin compound of Formula (Ia''), (Ib''), (Ic'') or (Id'')
is provided, wherein R.sub.3 is OH, R.sub.5 is H and R.sub.2 is
##STR00035##
and m1 and m2 are each independently an integer selected from 1 to
9. In even a further embodiment, R.sub.2 is
##STR00036##
[0073] In yet another embodiment of Formula (Ia''), (Ib''), (Ic'')
or (Id''), R.sub.2 is H, R.sub.3 is OH, and R.sub.5 is
##STR00037##
where m1 and m2 are each independently an integer selected from 1
to 9. In even a further embodiment, R.sub.2 is
##STR00038##
[0074] In one embodiment, a method for manufacturing a prostacyclin
compound of Formula (I), (Ia), (Ib), (Ic) or (Id) is provided where
R.sub.2 is a linear or branched C.sub.5-C.sub.18 alkyl. In a
further embodiment, R.sub.2 is 5-nonanyl, 4-heptanyl, 4-octanyl,
3-octanyl, 2-dimethyl-1-propanyl, 3,3-dimethyl-1-butanyl,
2-ethyl-1-butanyl, 3-pentanyl, pentyl, hexyl, heptyl, octyl, nonyl,
decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl,
hexadecyl, heptadecyl or octadecyl.
[0075] In one embodiment, a method for manufacturing a prostacyclin
compound of Formula (I), (Ia), (Ib), (Ic), (Id), (Ia'), (Ib'),
(Ic'), (Id'), (Ia''), (Ib''), (Ic'') or (Id'') is provided where
R.sub.2 is a linear or branched C.sub.5-C.sub.18 alkyl. In even a
further embodiment, R.sub.2 is a linear C.sub.5-C.sub.18 alkyl. In
another embodiment, R.sub.2 is
##STR00039##
where m1 and m2 are each independently an integer selected from 1
to 9 and each occurrence of R' is independently H, a linear or
branched C.sub.1-C.sub.8 alkyl, or a linear or branched
C.sub.1-C.sub.8 alkenyl. In even a further embodiment, R.sub.2
is
##STR00040##
[0076] In another embodiment, a method for manufacturing a
prostacyclin compound of Formula (I), (Ia), (Ib), (Ic) or (Id) is
provided wherein R.sub.2 is a branched C.sub.5-C.sub.18 alkyl. In a
further embodiment, R.sub.2 is 5-nonanyl, 4-heptyl, 4-octyl,
3-octyl, 2-dimethyl-1-propyl, 3,3-dimethyl-1-butyl,
2-ethyl-1-butyl, 3-pentyl, pentyl, hexyl, heptyl, octyl, nonyl,
decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl,
hexadecyl, heptadecyl or octadecyl.
[0077] In one embodiment of the invention, the prostacyclin
compound manufactured by the methods provided herein has the
following structure:
##STR00041##
wherein R.sub.1 is NH, O or S.
[0078] For example, R.sub.1 is O or N, and one of the following
compounds (5-nonanyl treprostinil (alkyl ester, 5C.sub.9-TR) or
5-nonanyl treprostinil (amide linked; 5C9-TR-A), is provided:
##STR00042##
[0079] In one embodiment, a method for manufacturing a prostacyclin
compound of Formula (I), (Ia), (Ib), (Ic) or (Id) is provided
wherein R.sub.2 is
##STR00043##
where m1 and m2 are each independently each an integer selected
from 1 to 9 and each occurrence of R' is independently H, a linear
or branched C.sub.1-C.sub.8 alkyl, or a linear or branched
C.sub.1-C.sub.8 alkenyl.
[0080] When m1 and/or m2 is an integer from 2-9, the m1/m2 at the
end of the carbon chain is CH.sub.3, while the remaining m1/m2
groups are CH.sub.2.
[0081] In even another embodiment, a method for manufacturing a
prostacyclin compound of Formula (I), (Ia), (Ib), (Ic), (Id),
(Ia'), (Ib'), (Ic'), (Id'), (Ia''), (Ib''), (Ic'') or (Id'') is
provided and R.sub.2 is
##STR00044##
[0082] The compounds provided herein can include a symmetrical
branched alkyl or an asymmetrical branched alkyl as the R.sub.2
moiety. For example, where R.sub.2 is
##STR00045##
m1 and m2 can be the same integer and R.sub.2 is therefore a
symmetrical branched alkyl. R.sub.2 is an asymmetrical branched
alkyl when m1 and m2 are different.
[0083] In another embodiment, a compound of Formula (I), (Ia),
(Ib), (Ic), (Id), (Ia'), (Ib'), (Ic'), (Id'), (Ia''), (Ib''),
(Ic'') or (Id'') is provided, R.sub.2 is
##STR00046##
m1 is 2 and m2 is 3, m1 and m2 are each independently 4, or m1 and
m2 are each independently 3 is provided via one of the methods
described herein.
[0084] In another embodiment, the prostacyclin compound
manufactured by the disclosed methods comprises an asymmetrical
branched alkyl at the R.sub.2 position, such as, for example,
3-hexanyl (3C.sub.6), 2-heptanyl (2C.sub.7), 3-heptanyl (3C.sub.7),
2-octanyl (2C.sub.8), 3-octanyl (3C.sub.8), or 4-octanyl
(4C.sub.8).
[0085] In another embodiment, a prostacyclin compound of Formula
(I), (Ia), (Ib), (Ic) or (Id) is manufactured by the disclosed
methods, wherein R.sub.2 is a branched alkyl selected from
2,2-diethyl-1-pentyl, 3-pentyl, 4-octyl, 5-nonanyl,
2-ethyl-1-butyl, 2-propyl-1-pentyl, 12-butyl-1-octyl,
2-dimethyl-1-propyl, and 3,3-dimethyl-1-butyl.
[0086] In yet another embodiment, a method for manufacturing a
prostacyclin compound of Formula (I), (Ia), (Ib), (Ic), (Id),
(Ia'), (Ib'), (Ic') or (Id') is provided, wherein, R.sub.2 is a
linear or branched C.sub.5-C.sub.18 alkenyl. For example, in one
embodiment, R.sub.2 is a linear C.sub.5-C.sub.18 alkenyl selected
from pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl,
undecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl,
heptadecenyl or octadecenyl. In a further embodiment, R.sub.3 is
OH. In another embodiment, R.sub.2 is a branched C.sub.5-C.sub.18
alkenyl selected from pentenyl, hexenyl, heptenyl, octenyl,
nonenyl, decenyl, undecenyl, tridecenyl, tetradecenyl,
pentadecenyl, hexadecenyl, heptadecenyl or octadecenyl. In a
further embodiment, R.sub.3 is OH.
[0087] In one embodiment, a prostacyclin compound of Formula (I),
(Ia), (Ib), (Ic) or (Id) is provided and R.sub.4 is
##STR00047##
is synthesized by one of the methods provided herein. In a further
embodiment, R.sub.4 is
##STR00048##
[0088] In one embodiment, a prostacyclin compound of Formula (I),
(Ia), (Ib), (Ic) or (Id) is synthesized by one of the methods
provided herein and R.sub.2 a linear C.sub.5-C.sub.18 alkyl,
R.sub.3 is OH and R.sub.4 is
##STR00049##
In a further embodiment, R.sub.2 is 5-nonanyl, 4-heptyl, 4-octanyl,
3-octanyl, 2-dimethyl-1-propyl, 3,3-dimethyl-1-butyl,
2-ethyl-1-butyl, 3-pentyl, pentyl, hexyl, heptyl, octyl, nonyl,
decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl,
hexadecyl, heptadecyl or octadecyl.
[0089] In one embodiment, a prostacyclin compound of Formula (I),
(Ia), (Ib), (Ic) or (Id) is synthesized by one of the methods
provided herein and R.sub.2 hexyl, dodecyl, tetradecyl, hexadecyl,
5-nonanyl, 4-heptanyl, 4-octanyl, 3-octanyl, 2-dimethyl-1-propyl,
3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, 3-pentyl, R.sub.3 is OH and
R.sub.4 is
##STR00050##
[0090] In one embodiment, a prostacyclin compound of Formula (I),
(Ia), (Ib), (Ic) or (Id) is synthesized by one of the methods
provided herein and R.sub.2 hexyl, R.sub.3 is OH and R.sub.4 is
##STR00051##
[0091] In one embodiment, a prostacyclin compound of Formula (I),
(Ia), (Ib), (Ic) or (Id) is synthesized by one of the methods
described herein and R.sub.2 hexyl, R.sub.3 is OH and R.sub.4
is
##STR00052##
[0092] In another embodiment, a method for manufacturing a
prostacyclin compound of Formula (Ia''), (Ib''), (Ic'') or (Id'')
is provided and R.sub.2 hexyl, R.sub.3 is OH R.sub.4 is H. In a
further embodiment, the prostacyclin compound is a compound of
Formula (Ic''). In yet another embodiment, a prostacyclin compound
of Formula (Ia''), (Ib''), (Ic'') or (Id'') is provided and R.sub.2
dodecyl, tetradecyl, pentadecyl or hexadecyl, R.sub.3 is OH R.sub.4
is H. In a further embodiment, the compound is a compound of
Formula (Ia''). In even a further embodiment, the compound is
present in a lipid nanoparticle formulation as described in more
detail below.
[0093] In one embodiment, a prostacyclin compound of Formula (I),
(Ia), (Ib), (Ic) or (Id), or pharmaceutically acceptable salt, is
synthesized by a method described herein, and R.sub.2 heptyl,
R.sub.3 is OH and R.sub.4 is
##STR00053##
[0094] In one embodiment, a prostacyclin compound of Formula (I),
(Ia), (Ib), (Ic) or (Id), or pharmaceutically acceptable salt, is
synthesized by a method described herein, and R.sub.2 octyl,
R.sub.3 is OH and R.sub.4 is
##STR00054##
[0095] In one embodiment, a prostacyclin compound of Formula (I),
(Ia), (Ib), (Ic) or (Id), or pharmaceutically acceptable salt, is
synthesized by a method described herein, and R.sub.2 nonyl,
R.sub.3 is OH and R.sub.4 is
##STR00055##
[0096] In another embodiment, a prostacyclin compound of Formula
(I), (Ia), (Ib), (Ic) or (Id), or pharmaceutically acceptable salt,
is synthesized by a method described herein, and R.sub.2 decyl,
R.sub.3 is OH and R.sub.4 is
##STR00056##
[0097] In yet another embodiment, a prostacyclin compound of
Formula (I), (Ia), (Ib), (Ic) or (Id), or pharmaceutically
acceptable salt, is synthesized by a method described herein, and
R.sub.2 undecyl, R.sub.3 is OH and R.sub.4 is
##STR00057##
[0098] In even another embodiment, a prostacyclin compound of
Formula (I), (Ia), (Ib), (Ic) or (Id), or pharmaceutically
acceptable salt, is synthesized by a method described herein, and
R.sub.2 dodecyl, R.sub.3 is OH and R.sub.4 is
##STR00058##
[0099] In one embodiment, a prostacyclin compound of Formula (I),
(Ia), (Ib), (Ic) or (Id), or pharmaceutically acceptable salt, is
synthesized by a method described herein, and R.sub.2 tridecyl,
R.sub.3 is OH and R.sub.4 is
##STR00059##
[0100] In another embodiment, a prostacyclin compound of Formula
(I), (Ia), (Ib), (Ic), or (Id), or pharmaceutically acceptable
salt, is synthesized by a method described herein, and R.sub.2
tetradecyl, R.sub.3 is OH and R.sub.4 is
##STR00060##
[0101] In even another embodiment, a prostacyclin compound of
Formula (I), (Ia), (Ib), (Ic) or (Id), or pharmaceutically
acceptable salt, is synthesized by a method described herein, and
R.sub.2 pentadecyl, R.sub.3 is OH and R.sub.4 is
##STR00061##
[0102] Another embodiment of the invention concerns a prostacyclin
compound of Formula (I), (Ia), (Ib), (Ic) or (Id), or
pharmaceutically acceptable salt is synthesized by a method
described herein, wherein R.sub.2 hexadecyl, R.sub.3 is OH and
R.sub.4 is
##STR00062##
[0103] Yet another embodiment of the invention concerns a
prostacyclin compound of Formula (I), (Ia), (Ib), (Ic) or (Id), a
or pharmaceutically acceptable salt is synthesized by a method
described herein, wherein R.sub.2 heptadecyl, R.sub.3 is OH and
R.sub.4 is
##STR00063##
[0104] Yet another embodiment of the invention concerns a
prostacyclin compound of Formula (I), (Ia), (Ib), (Ic) or (Id), or
a pharmaceutically acceptable salt is synthesized by a method
described herein, wherein R.sub.2 octadecyl, R.sub.3 is OH and
R.sub.4 is
##STR00064##
[0105] In one embodiment, a method is provided for manufacturing a
compound of Formula (I), (Ia), (Ib), (Ic) or (Id), or a
pharmaceutically acceptable salt, wherein one or more hydrogen
atoms is substituted with a deuterium. Accordingly, in one
embodiment, the present invention relates to an isotopologue of
Formula (I), (Ia), (Ib), (Ic) or (Id), substituted with one or more
deuterium atoms. The isotopologue of Formula (I), (Ia), (Ib), (Ic)
or (Id) may be used to accurately determine the concentration of
compounds of Formula (I), (Ia), (Ib), (Ic) or (Id) in biological
fluids and to determine metabolic patterns of compounds of Formula
(I), (Ia), (Ib), (Ic) or (Id) and its isotopologues.
[0106] In another embodiment of the invention, a method for
manufacturing a prostacyclin compound of Formula (II), or a
pharmaceutically acceptable salt thereof, is provided:
##STR00065##
wherein R.sub.1 is NH, O or S; R.sub.2 is a linear or branched
C.sub.5-C.sub.18 alkyl, a linear C.sub.2-C.sub.18 alkenyl or a
branched C.sub.3-C.sub.18 alkenyl, aryl, aryl-C.sub.1-C.sub.18
alkyl, an amino acid or a peptide; and n is an integer from 0 to
5.
[0107] In one embodiment, the method comprises manufacturing a
prostacyclin compound of Formula (II), or a pharmaceutically
acceptable salt thereof, wherein R.sub.1 is NH, O or S; R.sub.2 is
a linear or branched C.sub.5-C.sub.18 alkyl, a linear
C.sub.2-C.sub.18 alkenyl or a branched C.sub.3-C.sub.18 alkenyl;
and n is an integer from 0 to 5. In a further embodiment, n is 1
and R.sub.1 is NH or O.
[0108] In one embodiment, the method comprises manufacturing a
prostacyclin compound of Formula (II), wherein the prostacyclin
compound is a compound of formula (IIa), (IIb), (IIc) or (IId), or
a pharmaceutically acceptable salt thereof:
##STR00066##
[0109] wherein R.sub.2 is a linear or branched C.sub.5-C.sub.18
alkyl, a linear C.sub.2-C.sub.18 alkenyl or a branched
C.sub.3-C.sub.18 alkenyl, aryl, aryl-C.sub.1-C.sub.18 alkyl, an
amino acid or a peptide. In a further embodiment, a compound of
formula (IIa), (IIb), (IIc) or (IId) is provided wherein R.sub.2 is
a linear or branched C.sub.5-C.sub.18 alkyl, a linear
C.sub.2-C.sub.18 alkenyl or a branched C.sub.3-C.sub.18 alkenyl. In
one embodiment, a compound of Formula (II), (IIa), (IIb), (IIc) or
(IId) is provided, wherein one or more hydrogen atoms is
substituted with a deuterium. Accordingly, in one embodiment, the
present invention relates to an isotopologue of Formula (II),
(IIa), (IIb), (IIc) or (IId), substituted with one or more
deuterium atoms. The isotopologue of Formula (II), (IIa), (IIb),
(IIc) or (IId) may be used to accurately determine the
concentration of compounds of Formula (II), (IIa), (IIb), (IIc) or
(IId) in biological fluids and to determine metabolic patterns of
compounds of Formula (II), (IIa), (IIb), (IIc) or (IId) and its
isotopologues. The invention further provides compositions
comprising these deuterated isotopologues and methods of treating
diseases and conditions, as set forth herein.
[0110] In another embodiment, the method comprises manufacturing a
prostacyclin compound of Formula (IIc). In a further embodiment,
R.sub.2 is a linear C.sub.5-C.sub.18 alkyl or a branched
C.sub.5-C.sub.18 alkyl. For example, in one embodiment, R.sub.2 is
a linear C.sub.6-C.sub.18 alkyl. In another embodiment of Formula
(IIc), R.sub.2 is a linear C.sub.6-C.sub.10 alkyl. In even a
further embodiment of Formula (IIc), R.sub.2 is a hexyl, heptyl or
octyl.
[0111] Compounds of Formula (IIa) and Formula (IId) that can be
manufactured by the methods described herein are provided in tables
3 and 4 below.
TABLE-US-00003 TABLE 3 Compounds of Formula (IIa) R.sub.2 = linear
C.sub.5-C.sub.18 alkyl R.sub.2 = branched C.sub.5-C.sub.18 alkyl
R.sub.2 = linear C.sub.8 alkyl R.sub.2 = branched C.sub.6 alkyl
R.sub.2 = linear C.sub.6-C.sub.18 alkyl R.sub.2 = branched
C.sub.6-C.sub.18 alkyl R.sub.2 = linear C.sub.9 alkyl R.sub.2 =
branched C.sub.7 alkyl R.sub.2 = linear C.sub.7-C.sub.18 alkyl
R.sub.2 = branched C.sub.7-C.sub.18 alkyl R.sub.2 = linear C.sub.10
alkyl R.sub.2 = branched C.sub.8 alkyl R.sub.2 = linear
C.sub.8-C.sub.18 alkyl R.sub.2 = branched C.sub.8-C.sub.18 alkyl
R.sub.2 = linear C.sub.11 alkyl R.sub.2 = branched C.sub.9 alkyl
R.sub.2 = linear C.sub.9-C.sub.18 alkyl R.sub.2 = branched
C.sub.9-C.sub.18 alkyl R.sub.2 = linear C.sub.12 alkyl R.sub.2 =
branched C.sub.10 alkyl R.sub.2 = linear C.sub.10-C.sub.18 alkyl
R.sub.2 = branched C.sub.10-C.sub.18 alkyl R.sub.2 = linear
C.sub.13 alkyl R.sub.2 = branched C.sub.11 alkyl R.sub.2 = linear
C.sub.11-C.sub.18 alkyl R.sub.2 = branched C.sub.11-C.sub.18 alkyl
R.sub.2 = linear C.sub.14 alkyl R.sub.2 = branched C.sub.12 alkyl
R.sub.2 = linear C.sub.12-C.sub.18 alkyl R.sub.2 = branched
C.sub.12-C.sub.18 alkyl R.sub.2 = linear C.sub.15 alkyl R.sub.2 =
branched C.sub.13 alkyl
TABLE-US-00004 TABLE 4 Compounds of Formula (IIc) R.sub.2 = linear
C.sub.5-C.sub.18 alkyl R.sub.2 = branched C.sub.5-C.sub.18 alkyl
R.sub.2 = linear C.sub.6 alkyl R.sub.2 = branched C.sub.6 alkyl
R.sub.2 = linear C.sub.6-C.sub.18 alkyl R.sub.2 = branched
C.sub.6-C.sub.18 alkyl R.sub.2 = linear C.sub.7 alkyl R.sub.2 =
branched C.sub.7 alkyl R.sub.2 = linear C.sub.7-C.sub.18 alkyl
R.sub.2 = branched C.sub.7-C.sub.18 alkyl R.sub.2 = linear C.sub.8
alkyl R.sub.2 = branched C.sub.8 alkyl R.sub.2 = linear
C.sub.8-C.sub.18 alkyl R.sub.2 = branched C.sub.8-C.sub.18 alkyl
R.sub.2 = linear C.sub.9 alkyl R.sub.2 = branched C.sub.9 alkyl
R.sub.2 = linear C.sub.9-C.sub.18 alkyl R.sub.2 = branched
C.sub.9-C.sub.18 alkyl R.sub.2 = linear C.sub.10 alkyl R.sub.2 =
branched C.sub.10 alkyl R.sub.2 = linear C.sub.10-C.sub.18 alkyl
R.sub.2 = branched C.sub.10-C.sub.18 alkyl R.sub.2 = linear
C.sub.11 alkyl R.sub.2 = branched C.sub.11 alkyl R.sub.2 = linear
C.sub.5-C.sub.12 alkyl R.sub.2 = branched C.sub.5-C.sub.12 alkyl
R.sub.2 = linear C.sub.12 alkyl R.sub.2 = branched C.sub.12 alkyl
R.sub.2 = linear C.sub.6-C.sub.10 alkyl R.sub.2 = branched
C.sub.6-C.sub.10 alkyl R.sub.2 = linear C.sub.13 alkyl R.sub.2 =
branched C.sub.13 alkyl
[0112] Yet another embodiment of the invention relates to a method
for manufacturing a prostacyclin compound of Formula (III), or a
pharmaceutically acceptable salt thereof:
##STR00067##
[0113] wherein R.sub.1 and R.sub.2 are defined as provided for
Formula (I) and (II), and
[0114] R.sub.5 and R.sub.6 are independently selected from H,
optionally substituted linear or branched C.sub.1-C.sub.15 alkyl,
optionally substituted linear or branched C.sub.2-C.sub.15 alkenyl,
(C.dbd.O)-optionally substituted linear or branched
C.sub.1-C.sub.15 alkyl, or (C.dbd.O)-optionally substituted linear
or branched C.sub.2-C.sub.15 alkenyl, with the proviso that the
prostacyclin compound of Formula (III) is not treprostinil.
[0115] In one embodiment, the manufacturing methods provide
prostacyclin compounds that contain a chiral moiety at one or more
of the R.sub.2, R.sub.5 and/or R.sub.6 positions. For example, the
moiety at position R.sub.2, in one embodiment, is a chiral moiety
and comprises either the R isomer, the S isomer, or a mixture
thereof. An optical isomer at position R.sub.2, R.sub.5 and/or
R.sub.6 can also be classified with the D/L nomenclature. For
example, where R.sub.2 is an amino acid or an amino acid moiety,
the amino acid or amino acid moiety can be the D-isomer, L-isomer,
or a mixture thereof.
[0116] In one embodiment, one or more of the R.sub.2, R.sub.5
and/or R.sub.6 moieties is the R isomer or S isomer. In another
embodiment, one or more of the R.sub.2, R.sub.5 and/or R.sub.6
moieties provided herein comprise a mixture of R and S moieties.
The "R isomer" or "S isomer" as used herein refers to an
enantiomerically pure isomer. An "enantiomerically pure isomer" has
at least 90%, at least 95%, at least 96%, at least 97%, at least
98%, or at least 99% pure R- or S-isomer or when using the D/L
nomenclature, D- or L-isomer. A racemic compound is a compound
having a mixture in equal amounts of both enantiomers.
EXAMPLES
[0117] The present invention is further illustrated by reference to
the following Examples. However, it should be noted that these
Examples, like the embodiments described above, are illustrative
and are not to be construed as restricting the scope of the
invention in any way.
Example 1--Synthesis of Treprostinil Alkyl Esters
[0118] Treprostinil compounds derivatized with alkyl groups at the
carboxylic acid moiety were prepared. Specifically, treprostinil
was derivatized at the carboxylic acid moiety with C.sub.2,
C.sub.3, C.sub.4, C.sub.5, C.sub.6, C.sub.8, C.sub.10, C.sub.12,
C.sub.16, and C.sub.18 alkyl chains (i.e., R.sub.2 in Formula (A),
below, is C.sub.2, C.sub.3, C.sub.4, C.sub.5, C.sub.6, C.sub.8,
C.sub.10, C.sub.12, C.sub.16 or C.sub.18 alkyl) to make
treprostinil alkyl esters of various ester chain lengths.
Treprostinil can be synthesized, for example, by the methods
disclosed in U.S. Pat. Nos. 6,765,117 and 8,497,393. Synthesis of
prostaglandin derivatives is described in U.S. Pat. No. 4,668,814.
The disclosures of U.S. Pat. Nos. 6,765,117; 8,497,393 and
4,668,814 are each incorporated by reference in their entireties
for all purposes.
##STR00068##
[0119] Scheme 1:
[0120] Treprostinil esterification was catalyzed by strongly acidic
resin Amberlyst.RTM. 15 (Rohm and Haas). Treprostinil acid was
dissolved in anhydrous dioxane/alcohol at a concentration 10 mg/mL
(typically 4 mL). Alcohol (R.sub.2--OH) added was appropriate to
make corresponding chain length at the R.sub.2 group. By way of
example, for the C.sub.2 (ethyl ester) compound, the alcohol was
ethanol. The molar amount of alcohol in the solvent was ten times
the molar amount of treprostinil.
[0121] Treprostinil in dioxane/alcohol solution was added to washed
and dry Amberlyst resin. Per each 40 mg treprostinil, 1 g resin in
a glass vial was added. The mixture was placed on a shaker and
incubated overnight at 40.degree. C. Next, the liquid portion was
taken out of the vial, washed twice with 3 mL dioxane. All
recovered solvent was then collected. The solvent was dried by
nitrogen stream until the evaporation stopped. The remaining
treprostinil alkyl ester and nonvolatile alcohol (if long chain
alcohol used) was dissolved in 2 mL hexane/ethyl acetate 1:1, and
cleaned by liquid-liquid extraction vs. equal volume of phosphate
buffer, and then water. Next, the organic layer was separated and
dried by nitrogen stream and further in vacuum. If a long chain
alcohol used, an additional purification step was required to
separate alcohol by liquid chromatography. ACE CN, 5 .mu.m,
Ultra-Inert HPLC Column, 100.times.21.2 mm was used, with mobile
phase of hexane/propanol 98:2%.
[0122] Scheme 2:
[0123] To a solution of
(1R,2R,3aS,9aS)-[[2,3,3a,4,9,9a-hexahydro-2-hydroxy-1-[(3S)-3-hydroxyocty-
l]-1H-benz[f]inden-5-yl]oxy]acetic acid (treprostinil) (78.1 mg,
200 .mu.moles) dissolved in 1,4-dioxane (2.0 mL) was added
Amberlyst.RTM. 15 resin (2.0 g) and alcohol R.sub.2--OH (2.0
mmoles, 10 equivalents). The reaction mixture was heated to
40.degree. C. and allowed to shake at approximately 100 rpm for
18-196 hours. Solvent was removed and the resin was washed with
acetonitrile (MeCN) (3.times.3 mL). The 1,4-dioxane and MeCN
extracts were combined and dried using a gentle stream of warmed N2
gas and gentle heat to yield a thick waxy solid. The crude material
was dissolved in 20% .sup.nPrOH/Hexanes and submitted to
preparatory HPLC purification. Solvent was removed from the
purified material using a gentle stream of warmed N.sub.2 gas and
gentle heat to yield an off-white waxy solid. The pure material was
suspended in ethyl lactate for storage and was submitted to
analytical HPLC for concentration determination.
[0124] By way of example, the following compounds of Formula (A),
set forth in Table 5 were synthesized by the method of scheme
2.
TABLE-US-00005 TABLE 5 Compound R.sub.2 group abbreviation
##STR00069## C.sub.16-TR (C.sub.16) ##STR00070## C.sub.14-TR
(C.sub.14) ##STR00071## C.sub.12-TR (C.sub.12) ##STR00072##
C.sub.11-TR (C.sub.11) ##STR00073## C.sub.10-TR (C.sub.10)
##STR00074## C.sub.9-TR (2C.sub.9) ##STR00075## 5C.sub.9-TR
(5C.sub.9) ##STR00076## 2C.sub.9-TR (C.sub.9) ##STR00077##
(S)-2C.sub.9-TR ((S)-2C.sub.9) ##STR00078## (R)-2C.sub.9-TR
((R)-2C.sub.9) ##STR00079## C.sub.8-TR (C.sub.8) ##STR00080##
(S)-2C.sub.8-TR ((S)-2C.sub.8) ##STR00081## (R)-2C.sub.8-TR
((R)-2C.sub.8) ##STR00082## 3C.sub.8-TR (3C.sub.8) ##STR00083##
4C.sub.8-TR (4C.sub.8) ##STR00084## C.sub.6-TR (C.sub.6)
##STR00085## C.sub.5-TR (C.sub.5) ##STR00086## C.sub.4-TR (C.sub.4)
##STR00087## C.sub.3-TR (C.sub.3) ##STR00088## C.sub.2-TR
(C.sub.2)
[0125] A general diagram for synthesis of the alkyl ester of
treprostinil is shown in Scheme 1, below as well as FIG. 1. The
alcohol can be modified based on the desired alkyl ester chain
length (e.g., C.sub.5-C.sub.18 alkyl esters of even or odd chain
length, straight chain or branched). Other reaction conditions used
to synthesize treprostinil ester prodrugs are provided in Table 6,
below.
##STR00089##
TABLE-US-00006 TABLE 6 Coupling Entry Ester Solvent Reagent
Additive Time 1 C12TR Dioxane DCC DMAP 84 h (2 mL/100 .mu.mol TRP)
2 C12TR 10% DMF/DCM DCC DMAP 84 h 3 C12TR Dioxane Amberlyst-15 --
72 h (2 mL/100 .mu.mol TRP) 4 C12TR Dioxane Amberlyst-15 -- 18 h (1
mL/100 .mu.mol TRP) 5 C14TR Dioxane Amberlyst-15 -- 18 h (1 mL/100
.mu.mol TRP) 6 C14TR Dioxane Amberlyst-15 -- 18 h (1 mL/100 .mu.mol
TRP) 7 C14TR DMF DCC DMAP 18 h 8 C14TR DMF PyBOP TEA 18 h 9 C14TR
DMF HATU TEA 18 h 10 C14TR Dioxane Amberlyst-15 -- 168 h (2 mL/100
.mu.mol TRP) 11 5C9TR Dioxane Amberlyst-15 -- 72 h (1 mL/100
.mu.mol TRP) 12 5C9TR Dioxane Amberlyst-15 -- 72 h (1 mL/100
.mu.mol TRP) 13 5C9TR Dioxane Amberlyst-15 -- 168 h (1 mL/100
.mu.mol TRP) 14 5C9TR 10% DMF/DCM DCC DMAP 18 h 15 5C9TR 1:1
Dioxane:MeCN HATU -- 18 h 16 5C9TR 1:1 Dioxane:MeCN PyBOP -- 18 h
17 5C9TR DMF HATU -- 18 h 18 5C9TR DMF PyBOP -- 18 h 19 C16TR
Dioxane Amberlyst-15 -- 18 h (1 mL/100 .mu.mol TRP) 20 C16TR DCM
DCC DMAP 18 h 21 C16TR DCM PPh.sub.3, DEAD -- 18 h DCC =
N,N'-Dicyclohexylcarbodiimide; DMAP = 4-dimethylaminopyridine DMF =
N,N'-dimethylformamide; HATU =
1-[Bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium
3-oxid Hexafluorophosphate; PyBOP =
benzotriazol-1-yl-oxytripyrrolidinophosphonium
hexafluorophosphate
Example 2--Acylation of Treprostinil Derivatives
[0126] Treprostinil or treprostinil ester derivatives (e.g.,
derivatized with alkyl or alkenyl groups at the carboxylic acid
moiety as prepared in Example 1) are acylated as follows.
[0127] The compound of Example 1 (0.05 mol) or treprostinil is
dissolved in 10 mL of dichloromethane at 0.degree. C.
Dimethylaminopyridine is added (20 mol %), and then a solution of
an acyl chloride R(CO)Cl (2.1 equivalents) at 0.degree. C. (wherein
R is R.sub.5 or R.sub.6 as described herein) is added to the
compound of Example 1 or treprostinil. The solution is allowed to
stir and warm to 23.degree. C. over 1 hour. The reaction is
monitored by thin layer chromatography, and when no further change
is observed, the reaction is quenched with NaHCO.sub.3 (sat), and
the quenched mixture is extracted with dichloromethane (3.times.10
mL). The combined organic extracts are dried over anhydrous sodium
sulfate, and the solvent is removed under vacuum to afford the
crude product. Purification is effected by column chromatography on
silica gel with 2% methanol in dichloromethane.
[0128] A general scheme for synthesis of the acylated treprostinil
prodrugs and treprostinil derivative prodrugs is shown below and in
FIG. 2 (R.sub.2 is described herein, for example as H or a linear
or branched alkyl group):
##STR00090##
[0129] Other acylation techniques known in the art, including
selective acylation of each of the secondary alcohols, can be
employed. In addition, R.sub.2 can be selected such that the
R.sub.2 group can be selectively removed after acylation of the
secondary hydroxyl functionalities. Such protecting group
strategies are well known to those skilled in the art, and are
described in, e.g., Peter G. M. Wutes and Theodora W. Greene,
Greene's Protective Groups in Organic Synthesis, 4th Edition, Wiley
(2006), which is incorporated herein by reference in its entirety
for all purposes. An exemplary scheme of such a process is shown
below:
##STR00091##
[0130] Synthesis of C.sub.16TR-OAc:
##STR00092##
[0131] To a solution of Hexadecyl Treprostinil (C.sub.16TR) (78.1
mg, 200 .mu.moles) dissolved in 1,4-Dioxane (2.0 mL) was added
triethylamine (TEA) (98 .mu.L, 700 .mu.moles, 3.5 equivalents),
acetic anhydride (166 .mu.L, 1,760 .mu.moles, 8.8 equivalents), and
a catalytic amount of dimethylaminopyridine (DMAP). The reaction
mixture was allowed to shake at 40.degree. C. for 72 hours. Solvent
was removed under reduced pressure to yield a thick colorless oil.
The crude material was dissolved in hexanes and washed with a
solution of saturated NaHCO.sub.3 (3.times.5 mL). The organic
layers were combined and solvent was removed using a gentle stream
of warmed N2 gas and gentle heat to yield a thick colorless oil.
The crude material was dissolved in 20% .sup.nPrOH/Hexanes, passed
through a 0.45 .mu.m syringe filter, and submitted to preparatory
HPLC purification. Solvent was removed from the purified material
using a gentle stream of warmed N2 gas and gentle heat to yield a
thick colorless oil. The pure material was suspended in ethyl
lactate for storage and was submitted to analytical HPLC for
concentration determination.
[0132] C.sub.16-TR-OAc: 73% overall yield. The compound was also
characterized by NMR spectroscopy:
[0133] .sup.1H NMR (500 MHz, CDCl.sub.3) .delta. 0.89 (t, J=7.0 Hz,
6H), 1.17-1.32 (m, 33H), 1.43-1.46 (m, 2H), 1.49-1.66 (m, 8H),
1.89-1.93 (m, 1H), 1.99 (s, 3H), 2.06 (s, 3H), 2.30-2.35 (m, 2h),
2.47 (d of d, J=14.5 Hz, J=6.0 Hz, 1H), 2.55 (d of d, J=15.0 Hz,
J=6.0 Hz, 1H), 2.76 (d, of d, J=14.5 Hz, J=6.0 Hz, 1H), 2.90 (d of
d, J=15.0 Hz, J=6.0 Hz, 1H), 4.19 (t, J=7.0 Hz, 2H), 4.62 (s, 2H),
4.70-4.74 (m, 1H), 4.87 (p, J=6.0 Hz, 1H), 6.63 (d, J=8.0 Hz, 1H),
6.82 (d, J=8.0 Hz, 1H), 7.08 (t, J=8.0 Hz, 1H) ppm; .sup.13C NMR
(125 MHz, CDCl.sub.3) .delta. 14.2, 14.3, 21.5 (2), 22.7, 22.9,
25.1, 26.0 (2), 28.3, 28.8, 29.4, 29.6, 29.7, 29.8, 29.9, 31.9,
32.1, 33.6, 33.7, 34.3, 37.8, 40.7, 49.0, 65.6, 66.2, 74.6, 79.0,
109.8, 121.8, 126.4, 127.6, 140.7, 155.1, 169.6, 171.0, 171.1
ppm.
Example 3--Synthesis of Treprostinil Amide Derivatives
[0134] Treprostinil is available commercially, and can be
synthesized, for example, by the methods disclosed in U.S. Pat.
Nos. 6,765,117 and 8,497,393. Synthesis of prostaglandin
derivatives is described in U.S. Pat. No. 4,668,814. The
disclosures of U.S. Pat. Nos. 6,765,117; 8,497,393 and 4,668,814
are each incorporated by reference in their entireties for all
purposes.
[0135] To a solution of
(1R,2R,3aS,9aS)-[[2,3,3a,4,9,9a-hexahydro-2-hydroxy-1-[(3S)-3-hydroxyocty-
l]-1H-benz[f]inden-5-yl]oxy]acetic acid (i.e., treprostinil) (78.1
mg, 200 .mu.moles) dissolved in 1,4-Dioxane (2.0 mL) was added
triethylamine (TEA) (98 .mu.L, 700 .mu.moles, 3.5 equivalents),
alkylamine R.sub.1--NH.sub.2 (240 .mu.moles, 1.2 equivalents), and
a solution of PyBOP (364 mg, 700 .mu.moles, 3.5 equivalents)
dissolved in 2.0 mL MeCN (acetonitrile).
[0136] The reaction mixture was heated to 40.degree. C. and allowed
to shake at approximately 100 rpm overnight. Solvent was removed
under reduced pressure to yield the crude product as a thick yellow
oil. The product was extracted (1-1 extraction) from the oil by
repeated washings with 20% .sup.nPrOH/Hexanes (3.times.3 mL).
Solvent was removed from the organic extract using a gentle stream
of warmed N2 gas and gentle heat to yield a thick, slightly yellow
oil. The crude material was dissolved in 20% .sup.nPrOH/Hexanes,
passed through a 0.45 .mu.m syringe filter, and submitted to
preparatory HPLC purification. Solvent was removed from the
purified material using a gentle stream of warmed N.sub.2 gas and
gentle heat to yield a thick, colorless oil. The pure material was
suspended in ethyl lactate for storage and was submitted to
analytical HPLC for concentration determination.
[0137] The following treprostinil amide derivatives of Formula (B)
were made by the synthesis scheme provided above (Table 6).
Percentage yield is also provided where available.
##STR00093##
TABLE-US-00007 TABLE 7 Treprostinil amide derivatives Compound
R.sub.1 group Yield abbreviation ##STR00094## 88% C.sub.16-TR-A
(C.sub.16) ##STR00095## 71% C.sub.14-TR-A (C.sub.14) ##STR00096##
57% C.sub.12-TR-A (C.sub.12) ##STR00097## 62% C.sub.10-TR-A
(C.sub.10) ##STR00098## 47% C.sub.8-TR-A (C.sub.8) ##STR00099## 72%
.sup.tC.sub.8-TR-A (.sup.tC.sub.8) ##STR00100## 50% C.sub.6-TR-A
(C.sub.7) ##STR00101## 62% .sup.cC.sub.7-TR-A (.sup.cC.sub.7)
##STR00102## 65% 4C.sub.7-TR-A (4C.sub.7) ##STR00103## 58%
C.sub.6-TR-A (C.sub.6) ##STR00104## 77% C.sub.5-TR-A (C.sub.5)
##STR00105## 28% C.sub.4-TR-A (C.sub.4) ##STR00106## 12%
C.sub.3-TR-A (C.sub.3) ##STR00107## 12% C.sub.2-TR-A (C.sub.2)
##STR00108## 60% Phe-EE-TR-A (Phe-EE) ##STR00109## Not determined
Ala-EE-TR-A (Ala-EE) ##STR00110## Not determined Gly-EE-TR-A
(Gly-EE) ##STR00111## Not determined Leu-EE-TR-A (Leu-EE)
[0138] C.sub.6-TR-A and C.sub.12-TR-A were characterized by NMR
spectroscopy.
[0139] NMR Characterization of C.sub.6-TR-A
[0140] .sup.1H NMR (500 MHz, CDCl.sub.3) .delta. 0.90 (q, J=7.0 Hz,
6H), 1.17 (q, J=12.0 Hz, 1H), 1.30-1.70 (m, 18H), 1.81-1.83 (m,
1H), 1.80-1.93 (m, 1H), 2.20 (p, J=6.0 Hz, 1H), 2.22-2.23 (m, 1H),
2.47-2.54 (m, 2H), 2.75-2.82 (m, 2H), 3.16 (sextet, J=4.0 Hz, 1H),
3.35 (q, J=7.0 Hz, 2H), 3.63 (s, 1H), 3.70-3.80 (m, 1H), 4.48 (s,
2H), 6.55 (s, 1H), 6.70 (d, J=7.5 Hz, 1H), 6.85 (d, J=7.5 Hz, 1H),
7.11 (t, J=7.5 Hz, 1H) ppm; .sup.13C NMR (125 MHz, CDCl.sub.3)
.delta. 14.2, 14.3, 22.8, 22.9, 25.6, 26.4, 26.7(2), 28.8, 29.7,
31.6, 32.1, 33.0, 33.8, 35.1, 37.7, 39.2, 41.4, 41.6, 46.5, 52.4,
68.4, 72.8, 110.4, 122.2, 126.8, 127.3, 141.2, 154.5, 168.7 ppm;
HRMS (ESI, 2:2:1 MeCN, MeOH, H.sub.2O): m/z=474.35717
([M+H].sup.+).
[0141] NMR Characterization of C12-TR-A
[0142] HRMS (ESI, 2:2:1 MeCN, MeOH, H.sub.2O): m/z=558.45099
([M+H].sup.+).
[0143] While the described invention has been described with
reference to the specific embodiments thereof it should be
understood by those skilled in the art that various changes may be
made and equivalents may be substituted without departing from the
true spirit and scope of the invention. In addition, many
modifications may be made to adopt a particular situation,
material, composition of matter, process, process step or steps, to
the objective spirit and scope of the described invention. All such
modifications are intended to be within the scope of the claims
appended hereto.
[0144] Patents, patent applications, patent application
publications, journal articles and protocols referenced herein are
incorporated by reference in their entireties, for all
purposes.
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