U.S. patent application number 14/038675 was filed with the patent office on 2014-08-07 for process for the production of alpha-tocotrienol and derivatives.
This patent application is currently assigned to Edison Pharmaceuticals, Inc.. The applicant listed for this patent is Edison Pharmaceuticals, Inc.. Invention is credited to Andrew W. Hinman, Orion D. Jankowski, Kieron E. Wesson.
Application Number | 20140221674 14/038675 |
Document ID | / |
Family ID | 42118126 |
Filed Date | 2014-08-07 |
United States Patent
Application |
20140221674 |
Kind Code |
A1 |
Wesson; Kieron E. ; et
al. |
August 7, 2014 |
PROCESS FOR THE PRODUCTION OF ALPHA-TOCOTRIENOL AND DERIVATIVES
Abstract
The invention discloses novel processes for production,
enrichment and/or isolation of alpha-tocotrienol from source
material comprising at least one non-alpha-tocotrienol, such as
natural extracts comprising mixed tocotrienols.
Inventors: |
Wesson; Kieron E.;
(Burlingame, CA) ; Hinman; Andrew W.; (San
Francisco, CA) ; Jankowski; Orion D.; (Burlingame,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Edison Pharmaceuticals, Inc. |
Mountain View |
CA |
US |
|
|
Assignee: |
Edison Pharmaceuticals,
Inc.
Mountain View
CA
|
Family ID: |
42118126 |
Appl. No.: |
14/038675 |
Filed: |
September 26, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13358451 |
Jan 25, 2012 |
8575369 |
|
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14038675 |
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12606923 |
Oct 27, 2009 |
8106223 |
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13358451 |
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61197585 |
Oct 28, 2008 |
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Current U.S.
Class: |
549/413 ;
549/408; 568/361 |
Current CPC
Class: |
C07D 311/72 20130101;
C07C 46/02 20130101; C07C 50/28 20130101; C07C 46/02 20130101 |
Class at
Publication: |
549/413 ;
549/408; 568/361 |
International
Class: |
C07D 311/72 20060101
C07D311/72; C07C 46/02 20060101 C07C046/02 |
Claims
1. A process for the production, enrichment and/or isolation of
d-alpha-tocotrienol from a plant extract that comprises at least
one non-alpha tocotrienol and that optionally comprises
alpha-tocopherol and optionally comprises other tocols, non-tocols
and/or organic impurities, comprising the steps of: 1a.) reacting
the plant extract with suitable reagents which react with the one
or more non-alpha-tocols to introduce a functional group in the
free 5 and/or 7 position of the one or more non-alpha-tocols; 1b.)
separating the one or more non-alpha-tocols that have been
functionalized in step (1a) from the alpha-tocotrienol and optional
alpha tocopherol and other non-tocol compounds that may be present;
1c.) optionally further separating the alpha-tocotrienol in the
mixture separated in step (1b), from the optional alpha tocopherol
and from optional other non-tocols; 1d.) chemically reacting the
separated one or more non-alpha-tocols that have been
functionalized from step (1b) to give alpha-tocotrienol; and 1e.)
optionally combining the alpha-tocotrienol from step (1c) with the
alpha-tocotrienol from step (1d) to give alpha-tocotrienol.
2. The process of claim 1, wherein the plant extract is selected
from a palm oil extract, a palm fruit extract, a rice extract, a
rice bran extract, a barley extract, an annatto extract, or a
mixture thereof.
3. The process of claim 2, wherein the plant extract is a palm oil
extract.
4. The process of claim 2, wherein the plant extract is
Tocomin.RTM..
5. The process of claim 1, where the reaction in step (1a) is
amino-alkylation followed by acidification.
6. The process of claim 5, where the amino-alkylation is performed
with paraformaldehyde and a cyclic amine selected from
1-methylpiperazine, piperidine or morpholine.
7. The process of claim 5, where the amino-alkylation is performed
with paraformaldehyde and 1-methylpiperazine.
8. The process of claim 1, where the reducing agent is a hydride
reagent, a borane complex or an electron donor in the presence of a
suitable proton source.
9. The process of claim 8, where the reducing agent is sodium cyano
borohydride.
10. A process for the production, enrichment and/or isolation of
d-alpha-tocotrienol from an extract of palm oil which comprises at
least non-alpha tocotrienol and that optionally comprises
alpha-tocopherol and optionally comprises other tocols, non-tocols
and/or organic impurities, comprising the steps of: 2a.) reacting
the extract with amino-alkylating agents which react with the one
or more non-alpha-tocols to introduce a functional group in the
free 5 and/or 7 position of the one or more non-alpha tocotrienols
and converting the products into acid salts; 2b.) separating the
one or more non-alpha-tocotrienol acid salts of the products in
step (2a) from the alpha-tocotrienol, the optional alpha tocopherol
and the other optional non-tocol compounds that may be present; and
2c.) reducing the one or more non-alpha-tocotrienol functionalized
homologues with a reducing agent to give alpha-tocotrienol.
11. The process of claim 10, wherein the extract from palm oil is
Tocomin.RTM..
12. The process of claim 10, wherein the amino-alkylation is
performed with paraformaldehyde and a cyclic amine selected from
1-methylpiperazine, piperidine or morpholine.
13. The process of claim 10, where the amino-alkylation is
performed with paraformaldehyde and 1-methylpiperazine.
14. The process of claim 10, where the reducing agent is a hydride
reagent, a borane complex or an electron donor in the presence of a
suitable proton source.
15. The process of claim 14, where the reducing agent is sodium
cyano borohydride.
16. The process of claim 10, comprising an additional step wherein
the alpha-tocotrienol from step (2b) is recovered.
17. The process of claim 1, additionally comprising an additional
last step wherein the alpha-tocotrienol (from steps 1d and/or 1e)
is oxidized to alpha-tocotrienol quinone.
18. The process of claim 10, additionally comprising an additional
last step wherein the alpha-tocotrienol (from step 2c) is oxidized
to alpha-tocotrienol quinone.
19. The process of claim 1, additionally comprising a step 1b1)
after step 1b), wherein a solution of the non-alpha-tocols
homologues that have been functionalized is filtered.
20. The process of claim 10, additionally comprising a step 2b1)
after step 2b), wherein a solution of the non-alpha-tocols
homologues that have been functionalized is filtered.
21-28. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority benefit of U.S. provisional
patent application No. 61/197,585, filed Oct. 28, 2008. The content
of that application is incorporated herein by reference in its
entirety.
TECHNICAL FIELD
[0002] This invention relates generally to a process for
production, enrichment and/or isolation of pure alpha-tocotrienol
from natural extracts that comprise mixed tocols. In particular,
the invention relates to a novel and effective process for
production, enrichment and/or isolation of alpha-tocotrienol of
high purity from plant extracts, e.g. palm oil extract such as
Tocomin.RTM., that is economically feasible on a commercial scale.
The invention also relates to a process for the synthesis of
alpha-tocotrienol quinone of high purity. The invention also
relates to the alpha-tocotrienol-containing product produced by the
process.
BACKGROUND OF THE INVENTION
[0003] The present invention provides a process for the production,
enrichment and/or isolation of pure alpha-tocotrienol enriched
tocotrienol compositions from naturally occurring extracts, and to
the alpha-tocotrienol-containing product produced by the process.
This process can be performed without chromatography, or with
minimal use of chromatography, and is economically feasible on a
commercial scale.
[0004] Tocopherols and tocotrienols are molecules characterized by
a 6-chromanol ring structure and a side chain at the C-2-position.
Tocotrienols possess a 4', 8', 12' trimethyltridecyl unsaturated
phytol side chain with the presence of double bonds at 3',7', and
11' positions of the side chain, while tocopherols have a saturated
side chain. The geometry of each of these double bond sites is
trans (also referred to as E) in all four natural tocotrienols.
There are four naturally occurring tocotrienols, d-alpha-, d-beta-,
d-gamma-, and d-delta-tocotrienol. The four naturally occurring
tocotrienols have the (R) absolute configuration at the C-2 chroman
ring position.
TABLE-US-00001 ##STR00001## R.sup.1 R.sup.2 R.sup.3 Alpha-
tocotrienol ##STR00002## methyl methyl methyl Beta- tocotrienol
##STR00003## methyl H methyl Gamma- tocotrienol ##STR00004## H
methyl methyl Delta- tocotrienol ##STR00005## H H methyl Alpha-
tocopherol ##STR00006## methyl methyl methyl Beta- tocopherol
##STR00007## methyl H methyl Gamma- tocopherol ##STR00008## H
methyl methyl Delta- tocopherol ##STR00009## H H methyl
[0005] Tocotrienols are present in the oils, seeds, and other parts
of many plants used as foods (see pp. 99-165 in L. Machlin, ed.,
"Vitamin E: A Comprehensive Treatise" for a discussion of the
occurrence of tocotrienols in foods). Tocotrienol-containing
concentrates can be prepared from certain plant oils and plant oil
by-products such as rice bran oil or palm oil distillate. For
examples of such isolation processes, see for instance A. G. Top et
al., U.S. Pat. No. 5,190,618 (1993) or Tanaka, Y. et al, Japanese
Patent No. JP2003-171376 (2003).
[0006] There is a problem inherent in obtaining tocotrienols from
natural sources, in that the tocotrienol yield from such processes
is a mixture of varying amounts of all of the natural tocotrienols
and tocopherols. In order to obtain a pure member of the
tocotrienol family, it has been necessary to resort to very
expensive procedures such as preparative scale reverse-phase
chromatography or simulated moving bed chromatography. For an
example of such a purification process, see M. Kitano et al.,
Japanese Patent No. 2003-02777 (2003) or Burger et al., U.S. Pat.
No. 4,603,142.
[0007] The synthesis of tocotrienols in the natural form, having
the (2R) chiral configuration and trans double bonding at the
proper locations in the side chain, has also been proven to be of
considerable difficulty.
[0008] Syntheses of various members of the tocotrienol family in
the d,l- or (RS)-form have been published; see for example Schudel
et al., Helv. Chim. Acta (1963) 46, 2517 2526; H. Mayer et al.,
Helv. Chim. Acta (1967) 50, 1376 11393; H.-J. Kabbe et al.,
Synthesis (1978), 888 889; M. Kajiwara et al., Heterocycles (1980)
14, 1995 1998; S. Urano et al., Chem. Pharm. Bull. (1983) 31, 4341
4345, Pearce et al., J. Med Chem. (1992), 35, 3595 3606 and Pearce
et al., J. Med. Chem. (1994). 37, 526 541. None of these reported
processes lead to the natural form of the tocotrienols, but rather
produce racemic mixtures. Syntheses of natural form d-tocotrienols
have been published. See for example. J. Scott et al., Helv. Chim.
Acta (1976) 59, 290 306, Sato et al. (Japanese Patent 63063674);
Sato et al. (Japanese Patent No. JP 01233278) and Couladouros et al
(U.S. Pat. No. 7,038,067).
[0009] Tocotrienols occur largely in palm oil, rice bran oil, and
barley. While synthetic and natural tocopherols are readily
available in the market, the supply of natural tocotrienols is
limited, and generally comprises a mixture of tocotrienols. Crude
palm oil which is rich in tocotrienols (800-1500 ppm) offers a
potential source of natural tocotrienols. Carotech, located in
Malaysia, is an industrial plant able to extract and concentrate
tocotrienols from crude palm oil. Carotech uses a molecular
distillation process (employing ultra-high vacuum and very low
temperature) in its production plant. This process (see U.S. Pat.
No. 5,157,132) allows Carotech to extract phytonutrients such as
the Tocotrienol Complex (Tocomin.RTM., a registered trademark of
Carotech for extracts and concentrates of palm tree fruits) from
the crude palm oil. Tocomin.RTM.-50 typically comprises about
25.32% mixed tocotrienols (7.00% alpha-tocotrienol, 14.42% gamma
tocotrienol, 3.30% delta tocotrienol and 0.6% beta tocotrienol),
6.90% alpha-tocopherol and other phytonutrients such as plant
squalene, phytosterols, co-enzyme Q10 and mixed carotenoids.
[0010] Additional commercially available products that may be used
in the present invention are for example, Nu Triene
Tocotrienol.RTM. (30% content, a product of Eastman Chemical
Company), various Oryza.RTM. tocotrienol products of different
tocotrienol concentrations from Oryza Oil & Fat Co. Ltd
including Oryza tocotrienol-70 with 70% total
tocopherol/tocotrienol content, and a total tocotrienol content of
40% including 14% of alpha-tocotrienol and 24% gamma-tocotrienol,
and Oryza tocotrienol-90 with 90% total tocopherol/tocotrienol
content and a total tocotrienol content of 60%; Golden Hope
Plantations Berhad Tocotrienol oil (70% content), Davos Life
Science TRF (63% content), Ginnoway.TM. tocotrienol concentrate
from palm and rice oil from Beijing Gingko Group, Gold Trie.RTM. a
product of Sime Darby Biorganic Sdn Bhd and Palm Nutraceuticals Sdn
Bhd (89% content). Delta Tocotrienol-92.RTM. (92% pure by HPLC) is
a commercially available product from Beijing Gingko Group that may
be also used in the present invention.
[0011] Methods for isolation or enrichment of tocotrienol from
certain plant oils and plant oil by-products have been described in
the literature, but these methods generally produce mixtures of
natural tocols in varying amounts and are not economically feasible
on a commercial scale. As mentioned above, in order to obtain a
pure member of the tocotrienol family, it has been necessary to
resort to expensive procedures such as preparative scale
reversed-phase chromatography or simulated moving bed
chromatography. For some examples of such isolation and
purification processes, see for instance Top A. G. et al., U.S.
Pat. No. 5,190,618; Lane R et al., U.S. Pat. No. 6,239,171;
Bellafiore, L. et al U.S. Pat. No. 6,395,915; May, C. Y et al.,
U.S. Pat. No. 6,656,358; Jacobs, L et al, U.S. Pat. No. 6,838,104;
Sumner, C et al. Int. Pat. Pub. WO 99/38860, or Jacobs, L, Int.
Pat. Pub. WO 02/500054.
[0012] Production of d-alpha tocopherol from natural plant sources
has been described in U.S. Pat. No. 4,977,282, where natural plant
sources having Vitamin E activity of a concentrate of mixed
tocopherols that might include tocotrienols are transformed into
alpha-tocopherol. In this isolation, alpha tocopherol is enriched
after amino-alkylating the mixed tocopherols which are then reduced
by catalytic hydrogenation to convert the mixture of the non-alpha
tocopherol tocols into alpha-tocopherol. In this process, any
tocotrienols present would be hydrogenated to tocopherol. See
Netscher et al. (2007) Eur J. Org. Chem 1176-1183
[0013] Because of the similar molecular and retention
characteristics of the various individual tocopherols and
tocotrienols, separation of the individual compounds has been
proven difficult and not commercially viable. Although the process
for the production of alpha-tocotrienol has been described, it is
only available in pure form at very high prices (e.g., USD$672 for
100 mg of .gtoreq.98% pure alpha-tocotrienol from Fluka Chemical
Company in October, 2009).
[0014] In light of the above, there remains a need for a method of
producing the naturally occurring alpha-tocotrienol in a pure form
that is economically feasible on a commercial scale. Such a process
would minimize the number of processing steps required, and would
not require, or would minimize the use of, chromatographic
separations.
DISCLOSURE OF THE INVENTION
[0015] In accordance with the purposes of this invention, in one
aspect, this invention relates to a novel process for the
production, enrichment, and/or isolation of alpha-tocotrienol from
source material comprising at least one tocotrienol which is not
alpha-tocotrienol. In some embodiments, the at least one
tocotrienol which is not alpha-tocotrienol comprises
beta-tocotrienol, gamma-tocotrienol, or delta-tocotrienol; or any
two of beta-tocotrienol, gamma-tocotrienol, or delta-tocotrienol;
or all three of beta-tocotrienol, gamma-tocotrienol, and
delta-tocotrienol. In any of the foregoing embodiments, the source
material can optionally also comprise alpha tocopherol. In one
embodiment, this invention relates to a novel process for the
production, enrichment and/or isolation of pure alpha-tocotrienol
from plant extracts comprising naturally occurring mixed
tocotrienols. In one embodiment, this invention relates to a novel
process for the production, enrichment and/or isolation of pure
alpha-tocotrienol from plant extracts enriched in naturally
occurring mixed tocotrienols. In one embodiment the invention does
not need the use of chromatography, and is amenable to large
commercial production of alpha-tocotrienol. In another embodiment
the invention needs minimal use of chromatography and is amenable
to large commercial production of alpha-tocotrienol
[0016] In one embodiment, the invention relates to a novel process
for the production, enrichment and/or isolation of pure
alpha-tocotrienol from naturally occurring extracts comprising a
mixture of tocotrienols and alpha tocopherol. In another
embodiment, the naturally occurring extract is a palm oil extract,
a palm fruit extract, or a palm oil/palm fruit extract. In another
embodiment, the naturally occurring extract is a palm oil extract,
a palm fruit extract, or a palm oil/palm fruit extract which has
been concentrated. In another embodiment, the naturally occurring
extract is a palm oil extract, a palm fruit extract, or a palm
oil/palm fruit extract from Elaeis guineensis. In another
embodiment, the naturally occurring extract is a palm oil extract,
a palm fruit extract, or a palm oil/palm fruit extract from Elaeis
guineensis which has been concentrated. In another embodiment, the
naturally occurring extract is the commercial palm oil concentrate
Tocomin.RTM., a product of Carotech Bhd. (Malaysia), which
comprises a mixture of tocotrienols and alpha-tocopherol extracted
and concentrated from virgin crude palm oil/palm fruits (Elaeis
guineensis) and which also includes non-tocol phytonutrients such
as plant squalene, phytosterols, co-enzyme Q10 and mixed
carotenoids that are naturally extracted together with tocotrienols
from palm fruits. In some embodiments, the naturally occurring
extract is an extract of palm oil, rice bran oil, barley or
annatto, or any combination of two or more of the foregoing oils.
In another embodiment the formulation of the present invention
comprises an enriched tocotrienol extract from palm oil, as sold by
Carotech, Golden Hope Bioorganic, Davos Life Science, Beijing
Gingko Group, Eisai, Eastman Corporation, Sime Darby Biorganic Sdn
Bhd or Palm Nutraceuticals.
[0017] Another embodiment of the invention comprises the
production, enrichment and/or isolation of natural
d-alpha-tocotrienol from a material comprising at least one
compound selected from:
##STR00010##
[0018] reacting said material with a formaldehyde equivalent and at
least one amine compound of the formula H--N(R.sub.11)(R.sub.12),
where R.sub.1 and R.sub.12 are independently selected from the
group consisting of H and C.sub.1-C.sub.8 alkyl, or where R.sub.11
and R.sub.12 are combined together with the nitrogen to which they
are bonded to form a five-to-eight membered heterocyclic ring, said
heterocyclic ring having zero, one, or two additional heteroatoms
in addition to the nitrogen to which R.sub.11 and R.sub.12 are
bonded, to produce at least one aminomethylated compound selected
from:
##STR00011##
[0019] separating the aminomethylated compound or compounds from
non-aminomethylated compounds, and reducing the aminomethylated
compound or compounds to yield
##STR00012##
[0020] One embodiment of the invention, as described in FIG. 1,
comprises the production, enrichment and/or isolation of natural
d-alpha-tocotrienol from natural plant sources that comprise at
least one non-alpha tocotrienol, and optionally additional
tocotrienols, and that optionally also include alpha tocopherol and
optionally other tocols and optionally non-tocol phytonutrients or
impurities, comprising the steps of:
[0021] 1a.) reacting a plant extract mixture with suitable reagents
which will react with the one or more non-alpha-tocols to introduce
a functional group in the free 5 and/or 7 positions of the one or
more non-alpha-tocols;
[0022] 1b.) separating the one or more non-alpha-tocols homologues
that have been functionalized, from the alpha-tocotrienol, the
optional alpha tocopherol and other non-tocol compounds that may be
present;
[0023] 1c.) optionally further separating the alpha-tocotrienol in
the mixture separated in step (1b), from the optional alpha
tocopherol and other non-tocol compounds;
[0024] 1d.) chemically reacting the one or more non-alpha-tocol
functionalized homologues from step (1b) to give alpha-tocotrienol;
and
[0025] 1e.) optionally combining the alpha-tocotrienol from step
(1c) with the newly produced alpha-tocotrienol from step (1d) to
give alpha-tocotrienol of high purity.
[0026] In another embodiment, step 1b) is followed by an optional
step 1b1) of filtering a solution of the one or more
non-alpha-tocols homologues that have been functionalized.
Filtration can be performed using diatomaceous earth such as
Celite.RTM. or any other method of filtration known to the skilled
artisan.
[0027] In another embodiment, step 1d) is followed by an optional
step 1d1), wherein a solution of the alpha-tocotrienol (in a
solvent such as toluene) produced by the reduction is mixed with
silica gel. The silica gel is removed by filtration, and the
remaining filtrate is concentrated to give alpha-tocotrienol of
high purity.
[0028] In another embodiment, both steps 1b1) and 1d1) are
performed.
[0029] In another embodiment, the plant extract is a palm oil plant
extract. In another embodiment, the plant extract is a palm fruit
plant extract. In another embodiment, the plant extract is a rice
extract. In another embodiment, the plant extract is a rice bran
oil extract. In another embodiment, the plant extract is a barley
extract. In another embodiment, the plant extract is an annatto
extract. In another embodiment, the plant extract is a mixture of
two or more of the foregoing plant extracts.
[0030] In one embodiment, introduction of a functional group in the
free 5 and/or 7 positions of the non-alpha tocol homologues
comprises introduction of a group which provides for increased
differential solubility of the functionalized non-alpha tocol
homologues compared to non-functionalized compounds in the starting
material, source material, or extract. The increased differential
solubility can be differential solubility in a single solvent, or
increased differential solubility between two or more solvents in a
mixed solvent system. In one embodiment, the introduction of a
functional group in the free 5 and/or 7 positions of the non-alpha
tocol homologues is accomplished without reducing the double bonds
present in tocotrienol compounds and/or without causing
isomerization of the double bonds present in tocotrienol compounds.
In one embodiment, the step of chemically reacting the non-alpha
tocol functionalized homologues to produce alpha-tocotrienol is
accomplished without reducing the double bonds present in
tocotrienol compounds and/or without causing isomerization of the
double bonds present in tocotrienol compounds.
[0031] In one embodiment, the functionalization is introduced by
amino-alkylation followed by acidification, thus converting the
non-alpha-tocotrienol into the corresponding amino-alkylated
product and converting said products to acid salts. In some
embodiments, the functionalization is introduced by
amino-alkylation with a formaldehyde equivalent, such as
paraformaldehyde, and an amine, such as a secondary amine, such as
a cyclic amine such as 1-methylpiperazine, piperidine or
morpholine. In some embodiments, the functionalization is
introduced by amino-alkylation with paraformaldehyde and
1-methylpiperazine. In some embodiments, the functionalization is
introduced by amino-alkylation with paraformaldehyde and
morpholine.
[0032] In one embodiment, the separation of the amino-alkylation
products from the alpha-tocotrienol, the optional alpha tocopherol
and other non-tocol compounds that may be present is done by
partitioning between two organic layers. In one embodiment, the
separation of the amino-alkylation products from the
alpha-tocotrienol, the optional alpha tocopherol and other
non-tocol compounds that may be present is done by partitioning
between an organic layer and an aqueous layer. In one embodiment,
the separation of the amino-alkylation products from the
alpha-tocotrienol, the optional alpha tocopherol and other
non-tocol compounds that may be present is done by partitioning
using an acidic organic layer such as acetonitrile comprising
formic acid.
[0033] In another embodiment, the non-alpha-tocotrienol
functionalized homologues are reduced with a hydride reagent such
as sodium cyano borohydride (NaCNBH.sub.3). In another embodiment,
the non-alpha-tocotrienol functionalized homologues are reduced
with a hydride reagent such as sodium borohydride. In another
embodiment, the non-alpha-tocotrienol functionalized homologues are
reduced with lithium borohydride, zinc borohydride, or
tetraalkylammonium hydride. In yet another embodiment, the
non-alpha-tocotrienol functionalized homologues are reduced with a
hydride reagent such as lithium aluminum hydride. In yet another
embodiment, the non-alpha-tocotrienol functionalized homologues are
reduced with a borane, diborane, or a borane complex, such as
borane-t-butyl amine complex. In another embodiment, the
non-alpha-tocotrienol functionalized homologues are reduced
electrochemically or with an electron donor such as sodium,
lithium, magnesium, potassium, zinc, nickel, or amalgams thereof,
in the presence of a suitable proton source such as ammonium salts
or carboxylic acids.
[0034] In any of the embodiments above, the processes of the
invention can yield alpha-tocotrienol of high purity. In some
embodiments, the purity is in the range of 80% to 99.9%, or in the
range of 85% to 99.9%, or in the range of 90% to 99.9%, or in the
range of 95% to 99.9%. In some embodiments, the purity is in the
range of about 80% to about 99.9%, or in the range of about 85% to
about 99.9%, or in the range of about 90% to about 99.9%, or in the
range of about 95% to about 99.9%. In some embodiments, the purity
is more than 80%, or more than 85%, or more than 90%, or more than
91%, or more than 92%, or more than 93%, or more than 94%, or more
than 95%, or more than 96%, or more than 97%, or more than 98%, or
more than 99%, or more than 99.5%, or more than 99.9%. In some
embodiments, the purity is more than about 80%, or more than about
85%, or more than about 90%, or more than about 91%, or more than
about 92%, or more than about 93%, or more than about 94%, or more
than about 95%, or more than about 96%, or more than about 97%, or
more than about 98%, or more than about 99%, or more than about
99.5%, or more than about 99.9%. In other embodiments, the
impurities in the final product are less than 20%, or less than
15%, or less than 10%, or less than 5%, or less than 4%, or less
than 3%, or less than 2%, or less than 1%, or less than 0.5%, or
less than 0.1%. In other embodiments, the impurities in the final
product are less than about 20%, or less than about 15%, or less
than about 10%, or less than about 5%, or less than about 4%, or
less than about 3%, or less than about 2%, or less than about 1%,
or less than about 0.5%, or less than about 0.1%. In other
embodiments, the impurities consisting of tocols or tocol
derivatives in the final product are less than 5%, less than 4%,
less than 3%, less than 2%, less than 1%, less than 0.5% or less
than 0.1%. In other embodiments, the impurities consisting of
tocols or tocol derivatives in the final product are less than
about 5%, less than about 4%, less than about 3%, less than about
2%, less than about 1%, less than about 0.5% or less than about
0.1%. In one embodiment, the invention provides a method for
large-scale production, enrichment, and/or isolation of
alpha-tocotrienol, such as quantities of material containing
alpha-tocotrienol of at least 50 grams, at least 100 grams, at
least 250 grams, at least 500 grams, at least 1 kilogram, at least
2 kilograms, at least 5 kilograms, or at least 10 kilograms, or at
least about 50 grams, at least about 100 grams, at least about 250
grams, at least about 500 grams, at least about 1 kilogram, at
least about 2 kilograms, at least about 5 kilograms, or at least
about 10 kilograms. The quantity of material containing
alpha-tocotrienol can have any purity level as recited herein.
[0035] In some of the above mentioned embodiments, the process
involves an additional optional step, wherein the alpha-tocotrienol
of high purity is oxidized to produce alpha-tocotrienol quinone of
high purity. In one embodiment, the conversion of alpha-tocotrienol
to alpha-tocotrienol quinone is carried out under buffered
conditions. In one embodiment, the buffer and/or base employed
during conversion of alpha-tocotrienol to alpha-tocotrienol quinone
is sodium carbonate, sodium hydrogen carbonate, potassium
carbonate, potassium hydrogen carbonate, phosphate buffer, or any
mixture in any proportion of two or more of the foregoing
buffers.
[0036] In any of the embodiments above, the processes of the
invention can yield alpha-tocotrienol quinone of high purity. In
some embodiments, the purity is in the range of 80% to 99.9%, or in
the range of 85% to 99.9%, or in the range of 90% to 99.9%, or in
the range of 95% to 99.9%. In some embodiments, the purity is in
the range of about 80% to about 99.9%, or in the range of about 85%
to about 99.9%, or in the range of about 90% to about 99.9%, or in
the range of about 95% to about 99.9%. In some embodiments, the
purity is more than 80%, or more than 85%, or more than 90%, or
more than 91%, or more than 92%, or more than 93%, or more than
94%, or more than 95%, or more than 96%, or more than 97%, or more
than 98%, or more than 99%, or more than 99.5%, or more than 99.9%.
In some embodiments, the purity is more than about 80%, or more
than about 85%, or more than about 90%, or more than about 91%, or
more than about 92%, or more than about 93%, or more than about
94%, or more than about 95%, or more than about 96%, or more than
about 97%, or more than about 98%, or more than about 99%, or more
than about 99.5%, or more than about 09.9%. In other embodiments,
the impurities in the final product are less than 20%, or less than
15%, or less than 10%, or less than 5%, or less than 4%, or less
than 3%, or less than 2%, or less than 1%, or less than 0.5%, or
less than 0.1%. In other embodiments, the impurities in the final
product are less than about 20%, or less than about 15%, or less
than about 10%, or less than about 5%, or less than about 4%, or
less than about 3%, or less than about 2%, or less than about 1%,
or less than about 0.5%, or less than about 0.1%. In other
embodiments, the impurities consisting of tocols or tocol
derivatives in the final product are less than 5%, less than 4%,
less than 3%, less than 2%, less than 1%, less than 0.5% or less
than 0.1%. In other embodiments, the impurities consisting of
tocols or tocol derivatives in the final product are less than
about 5%, less than about 4%, less than about 3%, less than about
2%, less than about 1%, less than about 0.5% or less than about
0.1%. In one embodiment, the invention provides a method for
large-scale production, enrichment, and/or isolation of
alpha-tocotrienol quinone, such as quantities of material
containing alpha-tocotrienol quinone of at least 50 grams, at least
100 grams, at least 250 grams, at least 500 grams, at least 1
kilogram, at least 2 kilograms, at least 5 kilograms, or at least
10 kilograms, or at least about 50 grams, at least about 100 grams,
at least about 250 grams, at least about 500 grams, at least about
1 kilogram, at least about 2 kilograms, at least about 5 kilograms,
or at least about 10 kilograms. The quantity of material containing
alpha-tocotrienol quinone can have any purity level as recited
herein.
[0037] In another embodiment, the invention comprises a method for
oxidizing alpha-tocotrienol to alpha-tocotrienol quinone with
minimal isomerization of the double bonds of the triene moiety. In
some embodiments, the alpha-tocotrienol quinone,
2-((6E,10E)-3R-hydroxy-3,7,11,15-tetramethylhexadeca-6,10,14-trienyl)-3,5-
,6-trimethylcyclohexa-2,5-diene-1,4-dione, produced by the method
comprises at least about 80%, at least about 90%, at least about
95%, at least about 96%, at least about 97%, at least about 98%, at
least about 99%, at least about 99.5%, or at least about 99.9% of
the
2-(3-hydroxy-3,7,11,15-tetramethylhexadeca-6,10,14-trienyl)-3,5,6-trimeth-
ylcyclohexa-2,5-diene-1,4-dione material present.
[0038] In any of the above embodiments, the oxidation of
alpha-tocotrienol to alpha-tocotrienol quinone can be performed
with cerium (IV) ammonium nitrate.
[0039] In another embodiment, a solution of alpha-tocotrienol
quinone, in a solvent such as isopropylacetate, n-heptane, or a
mixture of isopropylacetate and n-heptane, is placed on a
chromatography column packed with silica gel. The silica gel can
contain between about 0.1-5% by weight of sodium hydrogen
carbonate, such as about 0.5-2% by weight or about 1% by weight of
sodium hydrogen carbonate. The alpha-tocotrienol quinone can be
eluted from the silica gel/NaHCO.sub.3 with solvents, such as
n-heptane, isopropylacetate, or n-heptane:isopropylacetate in
ratios of about 100:1, about 100:5, about 100:10, or about 100:15.
The recovered solution of alpha-tocotrienol quinone can be
concentrated to give alpha-tocotrienol quinone of high purity.
[0040] In another embodiment, the foregoing quantities of
alpha-tocotrienol or alpha-tocotrienol quinone can be produced
using a single performance of the method, that is, with a single
iteration of the steps of the method.
[0041] One embodiment of the invention, as described in FIG. 2,
comprises the production, enrichment and/or isolation of natural
d-alpha-tocotrienol from a natural plant source extract from palm
oil, wherein said extract comprises at least one non-alpha
tocotrienol, comprising the steps of:
[0042] 2a.) reacting a palm oil extract mixture with
amino-alkylating agents which will react with the one or more
non-alpha-tocols to introduce a functional group in the free 5
and/or 7 positions of the one or more non-alpha-tocotrienols and
converting the products into acid salts,
[0043] 2b.) separating the one or more non-alpha-tocotrienol acid
salts of the products from step (2a), from the alpha-tocotrienol,
optional alpha tocopherol and other non-tocol compounds that may be
present; and
[0044] 2c.) reducing the non-alpha-tocotrienol functionalized
homologues with a reducing agent to give alpha-tocotrienol of high
purity.
[0045] In this particular embodiment, the alpha-tocotrienol
separated from the one or more amino-alkyl tocotrienol homologues
in step (2b) is not recovered, thus allowing for a process yielding
pure alpha-tocotrienol without the need of intensive and/or
expensive chromatography.
[0046] In another embodiment, the process does not comprise an
additional step wherein the alpha-tocotrienol from step (2b) is
recovered, thus allowing for a more economical commercial
process.
[0047] In another embodiment, step 2b) is followed by an optional
step 2b1) of filtering a solution of the one or more
non-alpha-tocols homologues that have been functionalized.
Filtration can be performed using diatomaceous earth such as
Celite.RTM. or any other method of filtration known to the skilled
artisan.
[0048] In another embodiment, step 2c) is followed by an optional
step 2c1), wherein a solution of the alpha-tocotrienol (in a
solvent such as toluene) produced by the reduction is mixed with
silica gel. The silica gel is removed by filtration, and the
remaining filtrate is concentrated to give alpha-tocotrienol of
high purity.
[0049] In another embodiment, both step 2b1) and 2c1) are
performed.
[0050] In one embodiment, the palm oil extract is commercially
available Tocomin.RTM.. In another embodiment, the palm oil extract
is commercially available Tocomin.RTM.-50.
[0051] In one embodiment, introduction of an aminoalkyl group in
the free 5 and/or 7 positions of the non-alpha tocol homologues
provides for increased differential solubility of the
functionalized non-alpha tocol homologues compared to
non-functionalized compounds in the starting material, source
material, or extract. The increased differential solubility can be
differential solubility in a single solvent, or increased
differential solubility between two or more solvents in a mixed
solvent system. In one embodiment, the introduction of an
aminoalkyl group in the free 5 and/or 7 positions of the non-alpha
tocol homologues is accomplished without reducing the double bonds
present in tocotrienol compounds and/or without causing
isomerization of the double bonds present in tocotrienol compounds.
In one embodiment, the step of reducing the non-alpha tocol
functionalized homologues to produce alpha-tocotrienol is
accomplished without reducing the double bonds present in
tocotrienol compounds and/or without causing isomerization of the
double bonds present in tocotrienol compounds.
[0052] In another embodiment, the amino-alkylation is performed
with a formaldehyde equivalent, such as paraformaldehyde, and an
amine, such as a secondary amine, such as a cyclic amine selected
from 1-methylpiperazine, piperidine or morpholine. In yet another
embodiment the amino-alkylation is performed with paraformaldehyde
and 1-methylpiperazine. In yet another embodiment, the
amino-alkylation is performed with paraformaldehyde and
morpholine.
[0053] In another embodiment, the reduction is performed with a
hydride reagent such as lithium aluminum hydride, lithium
borohydride, zinc borohydride, tetraalkylammonium hydride, sodium
borohydride or sodium cyano borohydride.
[0054] In another embodiment, the reduction is performed with a
borane, diborane, or a borane complex, such as borane t-butyl amine
complex.
[0055] In another embodiment, the reduction is performed
electrochemically or with an electron donor such as sodium,
lithium, potassium, magnesium, zinc or nickel or amalgams thereof
in the presence of a suitable proton source, such as a protic
solvent such as an organic alcohol or liquid ammonia, or such as
ammonium salts or carboxylic acids.
[0056] In any of the embodiments above, the processes of the
invention can yield alpha-tocotrienol of high purity. In some
embodiments, the purity is in the range of 80% to 99.9%, or in the
range of 85% to 99.9%, or in the range of 90% to 99.9%, or in the
range of 95% to 99.9%. In some embodiments, the purity is in the
range of about 80% to about 99.9%, or in the range of about 85% to
about 99.9%, or in the range of about 90% to about 99.9%, or in the
range of about 95% to about 99.9%. In some embodiments, the purity
is more than 80%, or more than 85%, or more than 90%, or more than
91%, or more than 92%, or more than 93%, or more than 94%, or more
than 95%, or more than 96%, or more than 97%, or more than 98%, or
more than 99%, or more than 99.5%, or more than 99.9%. In some
embodiments, the purity is more than about 80%, or more than about
85%, or more than about 90%, or more than about 91%, or more than
about 92%, or more than about 93%, or more than about 94%, or more
than about 95%, or more than about 96%, or more than about 97%, or
more than about 98%, or more than about 99%, or more than about
99.5%, or more than about 99.9%. In other embodiments, the
impurities in the final product are less than 20%, or less than
15%, or less than 10%, or less than 5%, or less than 4%, or less
than 3%, or less than 2%, or less than 1%, or less than 0.5%, or
less than 0.1%. In other embodiments, the impurities in the final
product are less than about 20%, or less than about 15%, or less
than about 10%, or less than about 5%, or less than about 4%, or
less than about 3%, or less than about 2%, or less than about 1%,
or less than about 0.5%, or less than about 0.1%. In other
embodiments, the impurities consisting of tocols or tocol
derivatives in the final product are less than 5%, less than 4%,
less than 3%, less than 2%, less than 1%, less than 0.5% or less
than 0.1%. In other embodiments, the impurities consisting of
tocols or tocol derivatives in the final product are less than
about 5%, less than about 4%, less than about 3%, less than about
2%, less than about 1%, less than about 0.5% or less than about
0.1%. In one embodiment, the invention provides a method for
large-scale production, enrichment, and/or isolation of
alpha-tocotrienol, such as quantities of material containing
alpha-tocotrienol of at least 50 grams, at least 100 grams, at
least 250 grams, at least 500 grams, at least 1 kilogram, at least
2 kilograms, at least 5 kilograms, or at least 10 kilograms, or at
least about 50 grams, at least about 100 grams, at least about 250
grams, at least about 500 grams, at least about 1 kilogram, at
least about 2 kilograms, at least about 5 kilograms, or at least
about 10 kilograms. The quantity of material containing
alpha-tocotrienol can have any purity level as recited herein.
[0057] In some of the above mentioned embodiments, the process
involves an additional optional step, wherein the alpha-tocotrienol
of high purity is oxidized to produce alpha-tocotrienol quinone of
high purity. In one embodiment, the conversion of alpha-tocotrienol
to alpha-tocotrienol quinone is carried out under buffered
conditions. In one embodiment, the buffer and/or base employed
during conversion of alpha-tocotrienol to alpha-tocotrienol quinone
is sodium carbonate, sodium hydrogen carbonate, potassium
carbonate, potassium hydrogen carbonate, phosphate buffer, or any
mixture in any proportion of two or more of the foregoing
buffers.
[0058] In any of the embodiments above, the processes of the
invention can yield alpha-tocotrienol quinone of high purity. In
some embodiments, the purity is in the range of 80% to 99.9%, or in
the range of 85% to 99.9%, or in the range of 90% to 99.9%, or in
the range of 95% to 99.9%. In some embodiments, the purity is in
the range of about 80% to about 99.9%, or in the range of about 85%
to about 99.9%, or in the range of about 90% to about 99.9%, or in
the range of about 95% to about 99.9%. In some embodiments, the
purity is more than 80%, or more than 85%, or more than 90%, or
more than 91%, or more than 92%, or more than 93%, or more than
94%, or more than 95%, or more than 96%, or more than 97%, or more
than 98%, or more than 99%, or more than 99.5%, or more than 99.9%.
In some embodiments, the purity is more than about 80%, or more
than about 85%, or more than about 90%, or more than about 91%, or
more than about 92%, or more than about 93%, or more than about
94%, or more than about 95%, or more than about 96%, or more than
about 97%, or more than about 98%, or more than about 99%, or more
than about 99.5%, or more than about 99.9%. In other embodiments,
the impurities in the final product are less than 20%, or less than
15%, or less than 10%, or less than 5%, or less than 4%, or less
than 3%, or less than 2%, or less than 1%, or less than 0.5%, or
less than 0.1%. In other embodiments, the impurities in the final
product are less than about 20%, or less than about 15%, or less
than about 10%, or less than about 5%, or less than about 4%, or
less than about 3%, or less than about 2%, or less than about 1%,
or less than about 0.5%, or less than about 0.1%. In other
embodiments, the impurities consisting of tocols or tocol
derivatives in the final product are less than 5%, less than 4%,
less than 3%, less than 2%, less than 1%, less than 0.5% or less
than 0.1%. In other embodiments, the impurities consisting of
tocols or tocol derivatives in the final product are less than
about 5%, less than about 4%, less than about 3%, less than about
2%, less than about 1%, less than about 0.5% or less than about
0.1%. In one embodiment, the invention provides a method for
large-scale production, enrichment, and/or isolation of
alpha-tocotrienol quinone, such as quantities of material
containing alpha-tocotrienol quinone of at least 50 grams, at least
100 grams, at least 250 grams, at least 500 grams, at least 1
kilogram, at least 2 kilograms, at least 5 kilograms, or at least
10 kilograms, or at least about 50 grams, at least about 100 grams,
at least about 250 grams, at least about 500 grams, at least about
1 kilogram, at least about 2 kilograms, at least about 5 kilograms,
or at least about 10 kilograms. The quantity of material containing
alpha-tocotrienol quinone can have any purity level as recited
herein.
[0059] In another embodiment, the invention comprises a method for
oxidizing alpha-tocotrienol to alpha-tocotrienol quinone with
minimal isomerization of the double bonds of the triene moiety. In
some embodiments, the alpha-tocotrienol quinone,
2-((6E,10E)-3R-hydroxy-3,7,11,15-tetramethylhexadeca-6,10,14-trienyl)-3,5-
,6-trimethylcyclohexa-2,5-diene-1,4-dione, produced by the method
comprises at least about 80%, at least about 90%, at least about
95%, at least about 96%, at least about 97%, at least about 98%, at
least about 99%, at least about 99.5%, or at least about 99.9% of
the
2-(3-hydroxy-3,7,11,15-tetramethylhexadeca-6,10,14-trienyl)-3,5,6-trimeth-
ylcyclohexa-2,5-diene-1,4-dione material present.
[0060] In any of the above embodiments, the oxidation of
alpha-tocotrienol to alpha-tocotrienol quinone can be performed
with cerium (IV) ammonium nitrate.
[0061] In another embodiment, a solution of alpha-tocotrienol
quinone, in a solvent such as isopropylacetate, n-heptane, or a
mixture of isopropylacetate and n-heptane, is placed on a
chromatography column packed with silica gel. The silica gel can
contain between about 0.1-5% by weight of sodium hydrogen
carbonate, such as about 0.5-2% by weight or about 1% by weight of
sodium hydrogen carbonate. The alpha-tocotrienol quinone can be
eluted from the silica gel/NaHCO.sub.3 with solvents, such as
n-heptane, isopropylacetate, or n-heptane:isopropylacetate in
ratios of about 100:1, about 100:5, about 100:10, or about 100:15.
The recovered solution of alpha-tocotrienol quinone can be
concentrated to give alpha-tocotrienol quinone of high purity.
[0062] In another embodiment, the foregoing quantities of
alpha-tocotrienol or alpha-tocotrienol quinone can be produced
using a single performance of the method, that is, with a single
iteration of the steps of the method.
[0063] In some embodiments, as described in FIG. 3, the process
comprises the steps of:
[0064] 3a.) reacting a plant extract mixture, comprising at least
one non-alpha tocotrienol, with suitable reagents which will react
with the one or more non-alpha-tocols to introduce a functional
group in the free 5 and/or 7 positions of the one or more
non-alpha-tocols;
[0065] 3b.) separating the one or more non-alpha-tocol homologues
that have been functionalized, from the alpha-tocotrienol, the
optional alpha tocopherol and other non-tocol compounds that may be
present;
[0066] 3c.) optionally further separating the alpha-tocotrienol in
the mixture separated in step (3b), from the optional alpha
tocopherol and other non-tocol compounds;
[0067] 3d.) chemically reacting the one or more non-alpha-tocol
functionalized homologues to give alpha-tocotrienol;
[0068] 3e.) optionally combining the alpha-tocotrienol from step
(3c) with the newly produced alpha-tocotrienol from step (3d) to
give alpha-tocotrienol of high purity; and
[0069] 3f.) oxidizing the alpha-tocotrienol from step (3e) to give
alpha-tocotrienol quinone of high purity.
[0070] In another embodiment, step 3b) is followed by an optional
step 3b1) of filtering a solution of the one or more
non-alpha-tocols homologues that have been functionalized.
Filtration can be performed using diatomaceous earth such as
Celite.RTM. or any other method of filtration known to the skilled
artisan.
[0071] In another embodiment, step 3d) is followed by an optional
step 3d1), and/or step 3e) is followed by an optional step 3e1),
wherein a solution of the alpha-tocotrienol (in a solvent such as
toluene) produced by the reduction is mixed with silica gel. The
silica gel is removed by filtration, and the remaining filtrate is
concentrated to give alpha-tocotrienol of high purity.
[0072] In another embodiment, both steps 3b1) and 3d1), both steps
3b1) and 3e1), or all three steps 3b1), 3d1), and 3e1) are
performed.
[0073] In one embodiment, introduction of a functional group in the
free 5 and/or 7 positions of the non-alpha tocol homologues
comprises introduction of a group which provides for increased
differential solubility of the functionalized non-alpha tocol
homologues compared to non-functionalized compounds in the starting
material, source material, or extract. The increased differential
solubility can be differential solubility in a single solvent, or
increased differential solubility between two or more solvents in a
mixed solvent system. In one embodiment, the introduction of a
functional group in the free 5 and/or 7 positions of the non-alpha
tocol homologues is accomplished without reducing the double bonds
present in tocotrienol compounds and/or without causing
isomerization of the double bonds present in tocotrienol compounds.
In one embodiment, the step of chemically reacting the non-alpha
tocol functionalized homologues to produce alpha-tocotrienol is
accomplished without reducing the double bonds present in
tocotrienol compounds and/or without causing isomerization of the
double bonds present in tocotrienol compounds.
[0074] In one embodiment, the functionalization is introduced by
amino-alkylation followed by acidification, thus converting the
non-alpha-tocotrienol into the corresponding amino-alkylated
product and converting said products to acid salts. In some
embodiments, the functionalization is introduced by
amino-alkylation with a formaldehyde equivalent, such as
paraformaldehyde, and an amine, such as a secondary amine, such as
a cyclic amine such as 1-methylpiperazine, piperidine or
morpholine. In some embodiments, the functionalization is
introduced by amino-alkylation with paraformaldehyde and
1-methylpiperazine. In some embodiments, the functionalization is
introduced by amino-alkylation with paraformaldehyde and
morpholine.
[0075] In any of the embodiments above, the processes of the
invention can yield alpha-tocotrienol of high purity. In some
embodiments, the purity is in the range of 80% to 99.9%, or in the
range of 85% to 99.9%, or in the range of 90% to 99.9%, or in the
range of 95% to 99.9%. In some embodiments, the purity is in the
range of about 80% to about 99.9%, or in the range of about 85% to
about 99.9%, or in the range of about 90% to about 99.9%, or in the
range of about 95% to about 99.9%. In some embodiments, the purity
is more than 80%, or more than 85%, or more than 90%, or more than
91%, or more than 92%, or more than 93%, or more than 94%, or more
than 95%, or more than 96%, or more than 97%, or more than 98%, or
more than 99%, or more than 99.5%, or more than 99.9%. In some
embodiments, the purity is more than about 80%, or more than about
85%, or more than about 90%, or more than about 91%, or more than
about 92%, or more than about 93%, or more than about 94%, or more
than about 95%, or more than about 96%, or more than about 97%, or
more than about 98%, or more than about 99%, or more than about
99.5%, or more than about 99.9%. In other embodiments, the
impurities in the final product are less than 20%, or less than
15%, or less than 10%, or less than 5%, or less than 4%, or less
than 3%, or less than 2%, or less than 1%, or less than 0.5%, or
less than 0.1%. In other embodiments, the impurities in the final
product are less than about 20%, or less than about 15%, or less
than about 10%, or less than about 5%, or less than about 4%, or
less than about 3%, or less than about 2%, or less than about 1%,
or less than about 0.5%, or less than about 0.1%. In other
embodiments, the impurities consisting of tocols or tocol
derivatives in the final product are less than 5%, less than 4%,
less than 3%, less than 2%, less than 1%, less than 0.5% or less
than 0.1%. In other embodiments, the impurities consisting of
tocols or tocol derivatives in the final product are less than
about 5%, less than about 4%, less than about 3%, less than about
2%, less than about 1%, less than about 0.5% or less than about
0.1%. In one embodiment, the invention provides a method for
large-scale production, enrichment, and/or isolation of
alpha-tocotrienol, such as quantities of material containing
alpha-tocotrienol of at least 50 grams, at least 100 grams, at
least 250 grams, at least 500 grams, at least 1 kilogram, at least
2 kilograms, at least 5 kilograms, or at least 10 kilograms, or at
least about 50 grams, at least about 100 grams, at least about 250
grams, at least about 500 grams, at least about 1 kilogram, at
least about 2 kilograms, at least about 5 kilograms, or at least
about 10 kilograms. The quantity of material containing
alpha-tocotrienol can have any purity level as recited herein.
[0076] In any of the embodiments above, the processes of the
invention can yield alpha-tocotrienol quinone of high purity. In
some embodiments, the purity is in the range of 80% to 99.9%, or in
the range of 85% to 99.9%, or in the range of 90% to 99.9%, or in
the range of 95% to 99.9%. In some embodiments, the purity is in
the range of about 80% to about 99.9%, or in the range of about 85%
to about 99.9%, or in the range of about 90% to about 99.9%, or in
the range of about 95% to about 99.9%. In some embodiments, the
purity is more than 80%, or more than 85%, or more than 90%, or
more than 91%, or more than 92%, or more than 93%, or more than
94%, or more than 95%, or more than 96%, or more than 97%, or more
than 98%, or more than 99%, or more than 99.5%, or more than 99.9%.
In some embodiments, the purity is more than about 80%, or more
than about 85%, or more than about 90%, or more than about 91%, or
more than about 92%, or more than about 93%, or more than about
94%, or more than about 95%, or more than about 96%, or more than
about 97%, or more than about 98%, or more than about 99%, or more
than about 99.5%, or more than about 99.9%. In other embodiments,
the impurities in the final product are less than 20%, or less than
15%, or less than 10%, or less than 5%, or less than 4%, or less
than 3%, or less than 2%, or less than 1%, or less than 0.5%, or
less than 0.1%. In other embodiments, the impurities in the final
product are less than about 20%, or less than about 15%, or less
than about 10%, or less than about 5%, or less than about 4%, or
less than about 3%, or less than about 2%, or less than about 1%,
or less than about 0.5%, or less than about 0.1%. In other
embodiments, the impurities consisting of tocols or tocol
derivatives in the final product are less than 5%, less than 4%,
less than 3%, less than 2%, less than 1%, less than 0.5% or less
than 0.1%. In other embodiments, the impurities consisting of
tocols or tocol derivatives in the final product are less than
about 5%, less than about 4%, less than about 3%, less than about
2%, less than about 1%, less than about 0.5% or less than about
0.1%. In one embodiment, the invention provides a method for
large-scale production, enrichment, and/or isolation of
alpha-tocotrienol quinone, such as quantities of material
containing alpha-tocotrienol quinone of at least 50 grams, at least
100 grams, at least 250 grams, at least 500 grams, at least 1
kilogram, at least 2 kilograms, at least 5 kilograms, or at least
10 kilograms, or at least about 50 grams, at least about 100 grams,
at least about 250 grams, at least about 500 grams, at least about
1 kilogram, at least about 2 kilograms, at least about 5 kilograms,
or at least about 10 kilograms. The quantity of material containing
alpha-tocotrienol quinone can have any purity level as recited
herein.
[0077] In one embodiment, the conversion of alpha-tocotrienol to
alpha-tocotrienol quinone of step 3f) is carried out under buffered
conditions. In one embodiment, the buffer and/or base employed
during conversion of alpha-tocotrienol to alpha-tocotrienol quinone
of step 3f) is sodium carbonate, sodium hydrogen carbonate,
potassium carbonate, potassium hydrogen carbonate, phosphate
buffer, or any mixture in any proportion of two or more of the
foregoing buffers.
[0078] In another embodiment, the invention comprises a method for
oxidizing alpha-tocotrienol to alpha-tocotrienol quinone with
minimal isomerization of the double bonds of the triene moiety. In
some embodiments, the alpha-tocotrienol quinone,
2-((6E,10E)-3R-hydroxy-3,7,11,15-tetramethylhexadeca-6,10,14-trienyl)-3,5-
,6-trimethylcyclohexa-2,5-diene-1,4-dione, produced by the method
comprises at least about 80%, at least about 90%, at least about
95%, at least about 96%, at least about 97%, at least about 98%, at
least about 99%, at least about 99.5%, or at least about 99.9% of
the
2-(3-hydroxy-3,7,11,15-tetramethylhexadeca-6,10,14-trienyl)-3,5,6-trimeth-
ylcyclohexa-2,5-diene-1,4-dione material present.
[0079] In any of the above embodiments, the oxidation of
alpha-tocotrienol to alpha-tocotrienol quinone can be performed
with cerium (IV) ammonium nitrate.
[0080] In another embodiment, a solution of alpha-tocotrienol
quinone, in a solvent such as isopropylacetate, n-heptane, or a
mixture of isopropylacetate and n-heptane, is placed on a
chromatography column packed with silica gel. The silica gel can
contain between about 0.1-5% by weight of sodium hydrogen
carbonate, such as about 0.5-2% by weight or about 1% by weight of
sodium hydrogen carbonate. The alpha-tocotrienol quinone can be
eluted from the silica gel/NaHCO.sub.3 with solvents, such as
n-heptane, isopropylacetate, or n-heptane:isopropylacetate in
ratios of about 100:1, about 100:5, about 100:10, or about 100:15.
The recovered solution of alpha-tocotrienol quinone can be
concentrated to give alpha-tocotrienol quinone of high purity.
[0081] In another embodiment, the foregoing quantities of
alpha-tocotrienol or alpha-tocotrienol quinone can be produced
using a single performance of the method, that is, with a single
iteration of the steps of the method.
[0082] In some embodiments, as described in FIG. 4, the process
comprises the steps of:
[0083] 4a.) reacting a palm oil extract mixture, comprising at
least one non-alpha tocotrienol, with amino-alkylating agents which
will react with the one or more non-alpha-tocols to introduce a
functional group in the free 5 and/or 7 positions of the one or
more non-alpha-tocotrienols and converting the products into acid
salts;
[0084] 4b.) separating the one or more non-alpha-tocotrienol acid
salts of the products (from step 4a) from the alpha-tocotrienol,
optional alpha tocopherol and other non-tocol compounds that may be
present;
[0085] 4c.) reducing the one or more non-alpha-tocotrienol
functionalized homologues (from step 4b) with a reducing agent to
give alpha-tocotrienol of high purity; and
[0086] 4d.) oxidizing the alpha-tocotrienol from step (4c) to give
alpha-tocotrienol quinone of high purity.
[0087] In another embodiment, step 4b) is followed by an optional
step 4b1) of filtering a solution of the one or more
non-alpha-tocols homologues that have been functionalized.
Filtration can be performed using diatomaceous earth such as
Celite.RTM. or any other method of filtration known to the skilled
artisan.
[0088] In another embodiment, step 4c) is followed by an optional
step 4c1), wherein a solution of the alpha-tocotrienol (in a
solvent such as toluene) produced by the reduction is mixed with
silica gel. The silica gel is removed by filtration, and the
remaining filtrate is concentrated to give alpha-tocotrienol of
high purity.
[0089] In another embodiment, both steps 4b1) and 4c1) are
performed.
[0090] In one embodiment, the conversion of alpha-tocotrienol to
alpha-tocotrienol quinone of step 4d) is carried out under buffered
conditions. In one embodiment, the buffer and/or base employed
during conversion of alpha-tocotrienol to alpha-tocotrienol quinone
of step 4d) is sodium carbonate, sodium hydrogen carbonate,
potassium carbonate, potassium hydrogen carbonate, phosphate
buffer, or any mixture in any proportion of two or more of the
foregoing buffers.
[0091] In one embodiment, introduction of an aminoalkyl group in
the free 5 and/or 7 positions of the non-alpha tocol homologues
provides for increased differential solubility of the
functionalized non-alpha tocol homologues compared to
non-functionalized compounds in the starting material, source
material, or extract. The increased differential solubility can be
differential solubility in a single solvent, or increased
differential solubility between two or more solvents in a mixed
solvent system. In one embodiment, the introduction of an
aminoalkyl group in the free 5 and/or 7 positions of the non-alpha
tocol homologues is accomplished without reducing the double bonds
present in tocotrienol compounds and/or without causing
isomerization of the double bonds present in tocotrienol compounds.
In one embodiment, the step of reducing the non-alpha tocol
functionalized homologues to produce alpha-tocotrienol is
accomplished without reducing the double bonds present in
tocotrienol compounds and/or without causing isomerization of the
double bonds present in tocotrienol compounds.
[0092] In another embodiment, the amino-alkylation is performed
with a formaldehyde equivalent, such as paraformaldehyde, and an
amine, such as a secondary amine, such as a cyclic amine selected
from 1-methylpiperazine, piperidine or morpholine. In yet another
embodiment the amino-alkylation is performed with paraformaldehyde
and 1-methylpiperazine. In yet another embodiment, the
amino-alkylation is performed with paraformaldehyde and
morpholine.
[0093] In another embodiment, a solution of alpha-tocotrienol
quinone, in a solvent such as isopropylacetate, n-heptane, or a
mixture of isopropylacetate and n-heptane, is placed on a
chromatography column packed with silica gel. The silica gel can
contain between about 0.1-5% by weight of sodium hydrogen
carbonate, such as about 0.5-2% by weight or about 1% by weight of
sodium hydrogen carbonate. The alpha-tocotrienol quinone can be
eluted from the silica gel/NaHCO.sub.3 with solvents, such as
n-heptane, isopropylacetate, or n-heptane:isopropylacetate in
ratios of about 100:1, about 100:5, about 100:10, or about 100:15.
The recovered solution of alpha-tocotrienol quinone can be
concentrated to give alpha-tocotrienol quinone of high purity.
[0094] In any of the embodiments above, the processes of the
invention can yield alpha-tocotrienol of high purity. In some
embodiments, the purity is in the range of 80% to 99.9%, or in the
range of 85% to 99.9%, or in the range of 90% to 99.9%, or in the
range of 95% to 99.9%. In some embodiments, the purity is in the
range of about 80% to about 99.9%, or in the range of about 85% to
about 99.9%, or in the range of about 90% to about 99.9%, or in the
range of about 95% to about 99.9%. In some embodiments, the purity
is more than 80%, or more than 85%, or more than 90%, or more than
91%, or more than 92%, or more than 93%, or more than 94%, or more
than 95%, or more than 96%, or more than 97%, or more than 98%, or
more than 99%, or more than 99.5%, or more than 99.9%. In some
embodiments, the purity is more than about 80%, or more than about
85%, or more than about 90%, or more than about 91%, or more than
about 92%, or more than about 93%, or more than about 94%, or more
than about 95%, or more than about 96%, or more than about 97%, or
more than about 98%, or more than about 99%, or more than about
99.5%, or more than about 99.9%. In other embodiments, the
impurities in the final product are less than 20%, or less than
15%, or less than 10%, or less than 5%, or less than 4%, or less
than 3%, or less than 2%, or less than 1%, or less than 0.5%, or
less than 0.1%. In other embodiments, the impurities in the final
product are less than about 20%, or less than about 15%, or less
than about 10%, or less than about 5%, or less than about 4%, or
less than about 3%, or less than about 2%, or less than about 1%,
or less than about 0.5%, or less than about 0.1%. In other
embodiments, the impurities consisting of tocols or tocol
derivatives in the final product are less than 5%, less than 4%,
less than 3%, less than 2%, less than 1%, less than 0.5% or less
than 0.1%. In other embodiments, the impurities consisting of
tocols or tocol derivatives in the final product are less than
about 5%, less than about 4%, less than about 3%, less than about
2%, less than about 1%, less than about 0.5% or less than about
0.1%. In one embodiment, the invention provides a method for
large-scale production, enrichment, and/or isolation of
alpha-tocotrienol, such as quantities of material containing
alpha-tocotrienol of at least 50 grams, at least 100 grams, at
least 250 grams, at least 500 grams, at least 1 kilogram, at least
2 kilograms, at least 5 kilograms, or at least 10 kilograms, or at
least about 50 grams, at least about 100 grams, at least about 250
grams, at least about 500 grams, at least about 1 kilogram, at
least about 2 kilograms, at least about 5 kilograms, or at least
about 10 kilograms. The quantity of material containing
alpha-tocotrienol can have any purity level as recited herein.
[0095] In any of the processes for the production of
alpha-tocotrienol quinone described above, the alpha-tocotrienol
quinone is of high purity. In some processes, the purity is in the
range of 80% to 99%, or in the range of 85% to 99% or in the range
of 90% to 99%, or in the range of 95% to 99%. In some processes,
the purity is more than 80%, or more than 85%, more than 90%, or
more than 91%, or more than 92%, or more than 93%, or more than
94%, or more than 95%, or more than 96%, or more than 97%, or more
than 98%, or more than 99%, or more than 99.5%, or more than 99.9%.
In other embodiments, the impurities in the final product are less
than 20%, or less than 15%, or less than 10%, or less than 5%, or
less than 4%, or less than 3%, or less than 2%, or less than 1%, or
less than 0.5%, or less than 0.1%. In some embodiments, the
impurities consisting of tocols or tocol derivatives in the final
product are less than 5%, or less than 4%, or less than 3%, or less
than 2%, or less than 1%, or less than 0.5%, or less than 0.1%. In
some processes, the purity is in the range of about 80% to about
99%, or in the range of about 85% to about 99% or in the range of
about 90% to about 99%, or in the range of about 95% to about 99%.
In some processes, the purity is more than about 80%, or more than
about 85%, more than about 90%, or more than about 91%, or more
than about 92%, or more than about 93%, or more than about 94%, or
more than about 95%, or more than about 96%, or more than about
97%, or more than about 98%, or more than about 99%, or more than
about 99.5%, or more than about 99.9%. In other embodiments, the
impurities in the final product are less than about 20%, or less
than about 15%, or less than about 10%, or less than about 5%, or
less than about 4%, or less than about 3%, or less than about 2%,
or less than about 1%, or less than about 0.5%, or less than about
0.1%. In some embodiments, the impurities consisting of tocols or
tocol derivatives in the final product are less than about 5%, or
less than about 4%, or less than about 3%, or less than about 2%,
or less than about 1%, or less than about 0.5%, or less than about
0.1%.
[0096] In another embodiment, the invention comprises a method for
oxidizing alpha-tocotrienol to alpha-tocotrienol quinone with
minimal isomerization of the double bonds of the triene moiety. In
some embodiments, the alpha-tocotrienol quinone,
2-((6E,10E)-3R-hydroxy-3,7,11,15-tetramethylhexadeca-6,10,14-trienyl)-3,5-
,6-trimethylcyclohexa-2,5-diene-1,4-dione, produced by the method
comprises at least about 80%, at least about 90%, at least about
95%, at least about 96%, at least about 97%, at least about 98%, at
least about 99%, at least about 99.5%, or at least about 99.9% of
the
2-(3-hydroxy-3,7,11,15-tetramethylhexadeca-6,10,14-trienyl)-3,5,6-trimeth-
ylcyclohexa-2,5-diene-1,4-dione material present.
[0097] In any of the embodiments recited above, the non-alpha
tocols can be reacted with a formaldehyde equivalent and at least
one amine compound of the formula H--N(R.sub.11)(R.sub.12), where
R.sub.11 and R.sub.12 are independently selected from the group
consisting of H and C.sub.1-C.sub.8 alkyl, or where R.sub.11 and
R.sub.12 are combined together with the nitrogen to which they are
bonded to form a five-to-eight membered heterocyclic ring, said
heterocyclic ring having zero, one, or two additional heteroatoms
in addition to the nitrogen to which R.sub.11 and R.sub.12 are
bonded.
[0098] In any of the above embodiments, the oxidation of
alpha-tocotrienol to alpha-tocotrienol quinone can be performed
with cerium (IV) ammonium nitrate.
[0099] In another embodiment, the quantities of alpha-tocotrienol
or alpha-tocotrienol quinone described herein, at any level of
purity described herein, can be produced using a single performance
of a method recited herein, that is, with a single iteration of the
steps of the method.
BRIEF DESCRIPTION OF THE DRAWINGS
[0100] FIG. 1 is a flow chart depicting certain processes of the
invention.
[0101] FIG. 2 is a flow chart depicting additional processes of the
invention.
[0102] FIG. 3 is a flow chart depicting additional processes of the
invention.
[0103] FIG. 4 is a flow chart depicting additional processes of the
invention.
METHODS FOR CARRYING OUT THE INVENTION
[0104] The invention embraces a method for production, enrichment
and/or isolation of pure alpha-tocotrienol from natural extracts
that comprise mixed tocotrienols.
[0105] The term "tocols" refers to tocopherols and tocotrienols as
described herein.
[0106] The term "non-tocols" refers to phytonutrients or organic
materials that may be present in the extract, but are not
tocopherols or tocotrienols.
[0107] The term "amino-alkylation," also known as the Mannich
reaction, is a reaction that effects amino-alkyl addition. The
reaction can be conducted from at about room temperature up to
about 140.degree. C. for a sufficient length of time to effectuate
amino-alkylation. The reagents necessary are a source of
formaldehyde (a "formaldehyde equivalent") and an amine. Any
primary or secondary amine, including amines such as cyclic and
aromatic amines, alkyl amines, and polyamines, as well as ammonia,
can be used. Particular examples of suitable amines are dibutyl
amine, di-isopropyl amine, dimethyl amine, diethyl amine, dipropyl
amine, 1-methylpiperazine, N,N,N'-trimethylethylenediamine,
piperidine, pyrrolidine and morpholine. Sources of formaldehyde
(i.e., formaldehyde equivalents) include, but are not limited to,
paraformaldehyde, formaline, formaldehyde gas, trioxane and
hexamethylenetetramine. The relative molar concentration of the
formaldehyde equivalent and the amine are maintained in equimolar
amounts, but the relative concentrations may be varied as long as
there is at least one mole of amine and at least one mole of
formaldehyde for every mole of free aromatic position on the
tocotrienols, and, if present, any other compounds that will react
with the formaldehyde and amine reagents. Either the amine or
formaldehyde component may be present in an amount of from about 1
to about 20 moles per mole of free aromatic position on
tocotrienol, and, if present, any other compounds that will react
with the formaldehyde and amine reagents, particularly in a molar
amount of at least about four times greater than the free aromatic
positions on tocotrienol present, and, if present, any other
compounds that will react with the formaldehyde and amine reagents.
This process could also be accomplished step-wise, for example by
formylation followed by reductive amination, or by pre-formation of
the "Mannich" reagent--the alkyliminium or functional equivalent
intermediate.
[0108] The starting material is a mixed tocotrienol extract that
may also optionally comprise alpha tocopherol in amounts that may
vary depending on the source of the extract. Naturally produced
alpha-tocotrienol and optional alpha tocopherol are separated from
the beta, gamma, and delta-tocotrienol homologues of
alpha-tocotrienol, by reacting the mixture of tocotrienols and
optional alpha tocopherol with an appropriate reagent or reagents
to introduce a functional group at the free 5 and/or 7 positions of
the non-alpha-tocotrienols. For example, the starting material can
be amino-alkylated to introduce amino-alkylated groups on the beta,
gamma, and delta-tocotrienols. As alpha-tocotrienol does not have a
free ring position, any alpha-tocotrienol present in the mixture
will not be amino-alkylated. The amino-alkylated groups will allow
the separation of the amino-alkylated beta, gamma, and
delta-tocotrienols from alpha-tocotrienol, alpha tocopherol and
other non-tocol phytonutrients that may be present. The separation
will be accomplished by partitioning between different organic
solvents. Any non-polar organic solvents such as hexanes, heptanes,
pentanes, petroleum ether, or mixtures thereof, can be used to take
up the alpha tocopherol, alpha-tocotrienol and other phytonutrients
or hydrocarbon impurities. The amino-alkylated products, optionally
having been converted to an acid salt, can be partitioned in an
acidic organic layer such as acetonitrile comprising formic acid.
In another embodiment of the invention, the partitioning can be
performed between an organic layer and an aqueous layer.
Alternatively, the products from the amino-alkylation can be
removed by first permethylating to the tetra alkyl ammonium salt,
followed by reductive deamination under basic conditions (see for
example Maeda, Y. et al., JOC (1994) 59, 7897-7901; and Tayama, E.
et al, Chem Letters (2006) 35, 478-479).
[0109] By the term "reducing agent" is contemplated hydrides such
as lithium aluminum hydride, sodium borohydride, and sodium cyano
borohydride, borane complexes and electron donors such as sodium,
lithium, magnesium, potassium, zinc, nickel, or amalgams thereof in
the presence of a suitable proton source such as ammonium salts or
carboxylic acids.
[0110] The phrase "impurities consisting of tocols or tocol
derivatives in the final product" refers to beta-tocotrienol,
gamma-tocotrienol, delta-tocotrienol, alpha-tocopherol,
beta-tocopherol, gamma-tocopherol, or delta-tocopherol. Reference
to "impurities" in the final product, without further
specification, can refer to beta-tocotrienol, gamma-tocotrienol,
delta-tocotrienol, alpha-tocopherol, beta-tocopherol,
gamma-tocopherol, delta-tocopherol, and/or other non-tocol
impurities. In one embodiment, solvents which can be readily
removed by evaporation are not considered as impurities when
determining the percentage of impurities present.
[0111] The quinone (cyclohexadienedione) form and dihydroquinone
(benzenediol) form of the compounds disclosed herein are readily
interconverted with appropriate reagents. The quinone can be
treated in a biphasic mixture of an ethereal solvent with a basic
aqueous solution of Na.sub.2S.sub.2O.sub.4 (Vogel, A. I. et al.
Vogel's Textbook of Practical Organic Chemistry, 5.sup.th Edition,
Prentice Hall: New York, 1996; Section 9.6.14 Quinones, "Reduction
to the Hydroquinone"). Standard workup in the absence of oxygen
yields the desired hydroquinone. The hydroquinone form can be
oxidized to the quinone form with oxidizing agents such as ceric
ammonium nitrate (CAN) or ferric chloride. The quinone and
hydroquinone forms are also readily interconverted
electrochemically, as is well known in the art. See, e.g., Section
33.4 of Streitweiser & Heathcock, Introduction to Organic
Chemistry, New York: Macmillan, 1976.
[0112] Because reaction of alpha-tocopherol with cerium (IV)
ammonium nitrate generates nitric acid, the oxidation can be
carried out under buffered conditions. This can be accomplished by
including sodium carbonate, sodium hydrogen carbonate, other
carbonates such as potassium carbonate or potassium hydrogen
carbonate, phosphate buffers, other buffers, or mixtures of any two
or more of the foregoing buffers in any proportion, during the
oxidation. Removal of acid during oxidation reduces isomerization
of the double bonds in the triene moiety of the tocotrienol and
tocotrienol quinone. Buffered conditions can also be maintained
during workup of the alpha-tocotrienol quinone, for example, by
mixing a percentage of a solid buffer such as sodium hydrogen
carbonate with silica gel prior to placing the alpha-tocotrienol on
the silica gel for elution.
[0113] When silica gel is used in the workup, the grade of silica
gel used can be that used for standard preparative flash
chromatography. For example, silica gel of about 60 .ANG. pore size
with a particle distribution of about 40 to 63 microns can be used.
It can be used as is from the supplier, without further activation,
or can be activated by heating in air or an oxygen-containing
atmosphere.
[0114] This invention is further illustrated by the following
example of a preferred embodiment thereof. This example is included
merely for purposes of illustration and is not intended to limit
the scope of the invention.
Example
##STR00013##
[0115] General Procedures
[0116] All solvents and reagents were used as obtained from their
respective suppliers except as noted. .sup.1H and .sup.13C NMR were
obtained on a Varian Ultrashielded magnet at 400 MHz and 100 MHz
respectively in deuterated solvents as noted. All spectra are
referenced in ppm to either their residual solvent peak, as defined
in Gottlieb, H. E. et al.; J. Org. Chem. 1997, 62, 7512-7515, or
TMS at 0.00 ppm.
EXPERIMENTALS
Step 1--Aminomethylation.
##STR00014##
[0118] To Tocomin.TM.-50 (1.0 wt) was added paraformaldehyde (0.08
wt, 95%) and 1-Methylpiperazine (0.3 vol). The suspension was
stirred at room temperature for 30 min, and then at 75.degree. C.
for 2 to 3 h. The solution was heated at 125.degree. C. and
monitored for conversion of starting material components to product
components. The mixture was cooled to 30 to 40.degree. C., diluted
with acetonitrile (3.5 mL/g) and heptane (3.5 mL/g), and then
cooled to 5.degree. C., and treated dropwise with formic acid (1.0
vol). The bottom acetonitrile layer was separated and extracted
with heptane (2.times.3.5 mL/g). The acetonitrile layer was diluted
with tert-butyl methyl ether (3 mL/g) and cooled to 0.degree. C.
45% w/w aqueous tribasic potassium phosphate solution (7 mL/g) was
added dropwise (exothermic) so as to keep the temperature below
20.degree. C. The organic layer was separated at room temperature,
washed with saturated aqueous sodium chloride solution (23.1% w/w;
3 mL/g), and solvents were removed by distillation at up to
50.degree. C. under vacuum. To the concentrated solution was added
toluene (5 mL/g). Solvent (5 mL/g) was removed by distillation at
up to 50.degree. C. under vacuum. To the solution was added
additional toluene (5 mL/g). Solvent (5 mL/g) was removed by
distillation at up to 50.degree. C. under vacuum. The residue was
diluted with toluene (1.5 mL/g) and filtered through a pad of
Celite.TM. packed from a suspension in toluene. The Celite.TM. cake
was washed with toluene (1 mL/g). All filtrates were combined. The
reaction mass yield was determined by loss-on-drying analysis of an
aliquot of the reaction mixture. The solvents were removed by
distillation at up to 50.degree. C. under vacuum. The concentrated
solution of product aminomethylated tocols was used, as is, in Step
2.
Step 2--Reduction.
##STR00015##
[0120] Note: unless otherwise indicated, all relative weight (wt)
and volume (mL/g) equivalents in Step 2 are with respect to the
loss on drying figure determined at the end of Stage 1.
[0121] To the residue prepared in Step 1 was added toluene (8 vol).
A solvent exchange to a solution in 3-methylbutanol (3.0 vol) was
then prepared by distillation at up to 50.degree. C. under vacuum,
with additions of 3-methylbutanol.
[0122] To sodium cyanoborohydride (0.43 wt) was added
3-methylbutanol (2 vol) at room temperature. The suspension was
stirred at room temperature for 30 min, and then heated to
125.degree. C. To this preheated mixture was added over 1.5 h the
previously prepared solution of aminomethylated tocols in
3-methylbutanol (3.0 vol) followed by an additional rinse of
3-methylbutanol (0.5 vol). The mixture was heated at 125.degree. C.
and monitored for conversion of starting material components to
product components.
[0123] The mixture was cooled to 50.degree. C., diluted with
heptane (5 vol), then cooled to 0.degree. C., and treated with 45%
w/w aqueous tribasic potassium phosphate solution (5.0 vol)
(exothermic, gas evolution) so as to maintain a temperature below
25.degree. C. The two-phase mixture was stirred at room temperature
for 2 h, the organic layer was separated, washed with 45% w/w
aqueous tribasic potassium phosphate solution (3 vol), and
concentrated by distillation at up to 50.degree. C. under vacuum.
To the residue was added toluene (7 vol). The resulting solution
was added to a mixture of silica gel (2 wt) and toluene (5.5 vol)
with an additional rinse of toluene (2 vol). The silica gel
suspension was stirred at room temperature for 1 h. The silica gel
was removed by filtration and washed with toluene (2.times.5 vol).
The combined filtrates were concentrated by distillation at up to
50.degree. C. under vacuum. The residue solution was cooled to
30.degree. C. and transferred to a rotoevaporator with toluene
(2.times.1.4 vol) and further evaporated to dryness by distillation
at up to 60.degree. C. under vacuum to give alpha-tocotrienol.
.sup.1H-NMR (400 MHz, CDCl.sub.3)=5.17-5.05 (m, 3H), 4.16 (s, 1H),
2.61 (t, J=6.8 Hz, 2H), 2.16-2.01 (m, 6H), 2.16 (s, 3H), 2.12 (s,
3H), 2.11 (s, 3H), 2.01-1.93 (m, 4H), 1.87-1.73 (m, 2H), 1.68-1.49
(m, 2H), 1.68 (s, 3H), 1.60 (s, 6H), 1.58 (s, 3H), 1.25 (s,
3H).
Step 3--Chroman to Quinone Oxidation.
##STR00016##
[0125] Note: unless otherwise indicated, all relative weight (wt)
and volume (mL/g) equivalents in Step 3 are with respect to the
mass of this stage's starting material, the product of Step
2--alpha-tocotrienol.
[0126] The residue of Step 2 was dissolved in isopropyl acetate (10
vol), water (0.5 vol) was added, and the mixture was cooled to
0.degree. C. A solution of cerium (IV) ammonium nitrate (2.74 wt)
in water (3 vol) was prepared at room temperature and buffered by
addition of saturated aqueous sodium carbonate solution (17.4% w/w;
0.75 vol). The buffered cerium (IV) ammonium nitrate solution was
added over 30 min to the prepared mixture of alpha-tocotrienol from
step 2 in isopropylacetate and water while maintaining the
temperature at 0.degree. C. The mixture was stirred at 0.degree. C.
and monitored for conversion of starting material components to
product components. The organic layer was separated and treated for
2 h with a slurry of solid sodium hydrogen carbonate (2 wt) and
solid sodium sulfate (2 wt) in isopropylacetate (5 vol). The
suspension was filtered, the solids washed with isopropylacetate
(1.5 vol), and the combined filtrates treated with sodium hydrogen
carbonate (2.times.0.05 wt). The suspension was concentrated to a
maximum extent while maintaining an agitable mixture by
distillation at up to 45.degree. C. under vacuum. The residue was
cooled to 30.degree. C. and diluted with n-heptane (10 vol). A
chromatography column of silica gel (5 wt) and sodium hydrogen
carbonate (0.05 wt) was prepared from a slurry in n-heptane. The
mixture was eluted on the chromatography column and further eluted
with mixtures of n-heptane/isopropylacetate in relative
volume-ratios of 100:5 and then 100:10. Fractions were collected,
treated with solid sodium hydrogen carbonate (ca. 0.1 to 1 g/L
eluent), and analyzed for product content and purity. Acceptable
fractions were combined, treated with additional solid sodium
hydrogen carbonate (0.05 wt), and concentrated to a maximum extent
while maintaining an agitable mixture by distillation of solvent at
up to 45.degree. C. under vacuum. Isopropylacetate (1 to 3 vol) was
added and the mixture passed through a 0.45 to 1 um filter. The
filtrate was evaporated to dryness by distillation of solvent at up
to 40.degree. C. under vacuum to give the product,
alpha-tocotrienol quinone. .sup.1H-NMR (400 MHz, C.sub.6D.sub.6)
5.37-5.28 (t br m, J=7 Hz, 2H), 5.28-5.20 (t br m, J=6 Hz, 1H),
2.53-2.46 (m, 2H), 2.25-2.15 (m, 6H), 2.15-2.07 (m, 4H) 1.91 (s,
3H), 1.73-1.71 (br d, J=1 Hz, 3H), 1.71-1.70 (br d, J=1 Hz, 3H,
1.68 (s, 6H), 1.62 (s, 3H), 1.57 (s, 3H), 1.54-1.47 (m, 2H),
1.47-1.40 (ddd, J=8, 6, 1 Hz, 2H), 1.10 (s, 3H), 1.00 (s, 1H).
[0127] The disclosures of all publications, patents, patent
applications and published patent applications referred to herein
by an identifying citation are hereby incorporated herein by
reference in their entirety.
[0128] Although the foregoing invention has been described in some
detail by way of illustration and example for purposes of clarity
of understanding, it is apparent to those skilled in the art that
certain minor changes and modifications will be practiced.
Therefore, the description and examples should not be construed as
limiting the scope of the invention.
* * * * *