Note: Descriptions are shown in the official language in which they were submitted.
CA 02738235 2011-04-18
PROCESSES FOR THE PRODUCTION OF AMINOALICYL
GLUCOSAMINIDE PHOSPHATE AND DISACCHARIDE
IM-MIJNOEFFECTORS, AND INTERMEDIATES THEREFOR
CROSS-REFERENCES TO RELATED APPLICATIONS
=
15
BACKGROUND OF THE INVENTION
[0002] This invention relates to processes for the production of aminoalkyl
glucosaminide
phosphate (AGP) and of disaccharide compounds. Such compounds have been found
to be
immunoeffectors, adjuvants for vaccines and the like, and in addition, can
possess therapeutic
and/or prophylactic properties of their own. In addition, this invention
relates to processes
for the production of glycosyl halides, which can serve as intermediates in
the synthesis of
AGP compounds, disaccharides, and structurally related molecules.
[0003] Aminoalkyl glucosaminide phosphates are described in a number of
patents,
published patent applications, and journal articles. Such compounds in general
have five or
six acyl groups in the molecular structure, together with an "aglycon"
(nitrogen-containing
CA 02738235 2011-04-18
portion), which may be cyclical or acyclical. AGPs having acyclical aglycon
groups are
disclosed, for instance, in U.S. patents 6,113,918; 6,303,347 and 6,355,257.
AGPs having
cyclical aglycon groups are disclosed, for instance, in WO 02/012258.
[0004] The above-mentioned documents describe the production of the AGP
compounds
by two alternative processes. In one process a protected 3-0-acyloxyacylated
glycosyl halide
containing a phosphonate side Chain is coupled with an aminoalkanol or
aminoalkanetinol of
the type described in the patents. The reaction product is then selectively
acylated to provide
additional acyl groups, as described, and protecting groups are removed. In
the second
process, both the phosphonate side chain and the fatty acid groups are
incorporated after the
coupling reaction. Additional process information for producing AGP compounds
is
=
contained in Johnson et al., Bioorg. Med. Chem. Lett. 9:2273 (1999).
[0005] Disaccharides that may be produced by the processes described herein
include
components of the well known immunostimulant monophosphoryl lipid A
(contained, for
example in MPLO iramunostimulant (Corixa Corp.) Other disaccharides that may
be
produced are disclosed in, for instance, PCT application WO 01/90129 and U.S.
patents
6,013,640; 4,987,237; 4,912,094; 4,436,727; and 4,436,728. In U.S. patent
6,103,640 the
disaccharide was prepared by coupling an N-acyloxyacylated or N-protected
glycosyl
acceptor unit with a protected and/or 3-0-acyloxyacylated glycosyl donor unit.
The
protecting groups were variously benzyl (13n) and 2,2,2-
trich1oroethoxycaxbony1 (Troc)
groups. The glycosyl acceptor and donor units were constructed separately
using a series of
substituent protection and deprotection steps, beginning with the known
starting materials
benzyl- and 2-(trimethylsilyl)ethy1-2-amin.o-2-deoxy-4,6-0-isopropylidene-O-D-
glucopyranoside, respectively.
[0006] Glycosyl halides are used in many processes to introduce a glycoside
moiety into a
molecule, typically as part of a multistep synthesis in the field of
saccharide chemistry. They
are useful intermediates for incorporating a wide variety of groups, typically
by reaction with
nucleopl3iles, especially oxygen, sulfur, and nitrogen nucleophiles. It would
be advantageous
to provide a process for producing the AGP and disaccharide compounds using a
glycosyl
halide as a starting material.
[0007] Various ways of producing glycosyl halides have been described.
Generally, they
involve halogenation of an existing glycoside (which may contain typical
protecting groups
on reactive moieties such as amino or hydroxyl).
2
CA 02738235 2011-04-18
[0008] In U.S. patent 6,299,897, for example, an ethyl ester of the glycoside
in question (in
this instance, N-acetyl neuraminic acid) is reacted with acetyl chloride to
produce the
corresponding glycosyl chloride. In U.S. patent 5,843,463, a glycosyl chloride
V,produced
by reacting the glycoside in question (3-0-ally1-5-0-benzy1-1,2-0-
methoxybenzylidene-
alpha-D-ribofuranose) with trimethylsily1 chloride. The reaction is conducted
by mixing the
two reactants or by dissolving the glycoside in the trimethylsilyl chloride.
[0009] U.S. patent 4,613, 590 discloses a process for preparation of glycosyl
chloride by
treatment of the glycoside with titanium tetrachloride. In Sugiyama et al.,
Org. Left. 2:2713
(2000), glycosyl chlorides were prepared by reaction of thioglycosides with
chlorosulfoniun
chloride.
[0010] Kovac, Carbohydr. Res. 245: 219 (2993) prepared a glycosyl chloride by
reaction
of the glycoside with dichloromethyl methyl ether and zinc chloride. Takeo et
al.,
Carbohydr. Res. 245: 81(1993) produced a glycosyl chloride by reaction with
chlorine.
Magnusson et al., J. Org. Chem. 55:3181(1990) produced a glycosyl chloride by
reaction of
the 2-(trimethylsilyDethyl glycoside with 1,1-dichloromethyl methyl ether in
the presence of
a catalytic amount of zinc chloride.
SUMMARY OF THE INVENTION
100111 This invention relates to a group of related novel processes for the
production of
aminoalkyl glucosaminide phosphates and of disaccharides, together with
intermediate
processes And compounds.
[0012] In one aspect, the invention comprises processes for the production of
aminoalkyl
ghicosaminide (AGP) compounds.
[0013] In a second aspect the invention relates to a process for producing
glycosyl halides
that comprises reacting a silyl glycoside with a dihalomethyl alkyl ether in
the presence of
zinc chloride, zinc bromide, boron trifluoride, or a similar Lewis acid. This
step also
comprises the first of a two-step process for removing an anomeric silyl
protecting group
from the silyl glycoside by first reacting it to produce a glycosyl halide,
which is then reacted
it with a silver salt in the presence of water to produce a heraiacetal.
3
CA 02738235 2014-04-01
- 3a -
According to an aspect of the invention, there is provided a method for
preparing an aminoalkyl glucosaminide 4-phosphate compound having the formula:
Ole
Rso 0
X
Y
0 -
,
0 Nil
RIO
(CH-Aa13,
R-0
(ellz/CR4
wherein X is
spprZ if k )rii
( R.111
i? N
0
or
RII0
(C142V-143
F,2
4 . 44 bidA"-R,T
R4 (Cli),
i 0
R6
OR.3=;
(CH2)1C113
CA 02738235 2014-04-01
- 3h -
Y is -0- or -NH; R1 and R2 are each independently selected from saturated and
unsaturated (C2-C24) aliphatic acyl groups; R8 is -H or -P03R11.-.rc11a,
wherein R11 and
R1la are each independently -H or (C1-C4) aliphatic groups; R9 is H, -CH3 or -
PO3R13aR14, wherein R13a and R14 are each independently selected from -H and
(CI-
S C4) aliphatic groups; and wherein at least one of R8 and R9 is a phosphorus-
containing group, but R8 and R9 are not both phosphorus-containing groups;
wherein
the subscripts n, m, p, q, n', rn', p' and q' are each independently an
integer of from 0
to 6, provided that the sum of p' and m' is an integer from 0 to 6, and the
subscript r is
independently an integer of from 2 to 10; R3 and R12 are independently
saturated or
unsaturated aliphatic (C2-C24) acyl groups; R4 and R5 are independently
selected from
H and methyl; R8 and R7 are independently selected from H, OH, (C1-C4)
oxyaliphatic
groups, -P03H2, -0P03H2, -S03H, -0S03H, -NR15R16, -SR15, -CN, -NO2, -CHO, -
CO2R151-00NR15R16, -P03R15R16, -0P03R15R16, -S03R15 and -0S03R15, wherein R15
and R16 are each independently selected from H and (C1-C4) aliphatic groups;
R13 is
independently selected from H, OH, (C1-C4) oxyaliphatic groups, -P03R17R18,
_0p03R17¨K18,
S03R17, -0S03R17, -NR17R18, -CN, -NO2, -CHO, -0O2R17, and
-00NR17R18, wherein R17 and R18 are each independently selected from H and (C1-
C4) aliphatic groups; and Z is -0- or -S-;
comprising:
(a) selectively 6-0-silylating a 2-amino-2-deoxy-6-D-glucopyranose derivative
having
the formula;
CA 02738235 2014-04-01
- 3c -
OH
Rs
HO a N q RI' or
NH R4 CH PG
PG
OH
Rot
fj; w
110 le
NE R4
N
PG-
wherein B is 0 or S; and PG independently represents a protecting group that
forms
an ester, an ether or a carbonate with the oxygen atom of a hydroxy group or
that
forms an amide or a carbamate with the nitrogen atom of an amino group,
respectively;
with a trisubstituted chlorosilane RJRbRcSi-CI wherein Ra, Rb, and RG are
independently selected from the group consisting of C1-C6 alkyl, C3-C6
cycloalkyl, and
optionally substituted phenyl, in the presence of a tertiary amine, to give a
6-silylated
derivative;
(b) selectively acylating the 4-0H position of the resulting 6-0-silylated
derivative
with an (R)-3-alkanoyloxyalkanoic acid or a hydroxy-protected (R)-3-
hydroxyalkanoic
acid in the presence of a carbodiimide reagent and catalytic 4-
dimethylaminopyridine
or 4- pyrrolidinopyridine to give a 4-0-acylated derivative;
CA 02738235 2014-04-01
- 3d -
(c) selectively deprotecting the nitrogen protecting groups, sequentially or
simultaneously, and N,N-diacylating the resulting diamine with an (R)-3-
alkanoyloxyalkanoic acid or a hydroxy-protected (R)-3-hydroxyalkanoic acid in
the
presence of a peptide coupling reagent;
(d) introducing a protected phosphate group at the 4-position with a
chlorophosphate
or phosphoramidite reagent to give a phosphotriester; and
(e) simultaneously or sequentially deprotecting the phosphate, silyl, and
remaining
protecting groups.
According to another aspect of the invention, there is provided a method for
preparing an aminoalkyl glucosaminide 4-phosphate compound having the formula:
CA 02738235 2014-04-01
- 3 e -
0 It9
11
0 - -
-- Nil
P.I0
(CHAC:
kl0
(CII;Oreg3
wherein X is
S'Pr
( le3
P.' N
0
1 or
RI 10 ---
(C1421,C113
R4 (Cli2)0 0
i
R6
OM
(CH2:4C1I3
CA 02738235 2014-04-01
- 3f-
Y is -0- or -NH; R1 and R2 are each independently selected from saturated and
unsaturated (C2-C24) aliphatic acyl groups; R8 is -H orpo3R,-
wherein R11 and
alla are each independently -H or (C1-C4) aliphatic groups; R9 is -H, -CH3 or -
PO3R13aR14, wherein R13a and R14 are each independently selected from -H and
(C1-
C4) aliphatic groups; and wherein at least one of R8 and R9 is a phosphorus-
containing group, but R8 and R9 are not both phosphorus-containing groups;
wherein
the subscripts n, m, p, q, n', m', p' and q' are each independently an integer
of from 0
to 6, provided that the sum of p' and m' is an integer from 0 to 6, and the
subscript r is
independently an integer of from 2 to 10; R3 and R12 are independently
saturated or
unsaturated aliphatic (C2-C24) acyl groups; R4 and R5 are independently
selected
from H and methyl; R6 and R7 are independently selected from H, OH, (C1-C4)
oxyaliphatic groups, -P03H2, -0P03H2, -S03H, -0S03H, -NR15R16, -SR15, -CN, -
NO2, -
CHO, -0O2R15, -CONR15R16, -P03R15R16, ..0P03R15R16, -S03R15 and -0S03R15,
wherein R15 and R16 are each independently selected from H and (C,-C4)
aliphatic
groups; R13 is independently selected from 1-1, OH, (C1-C4) oxyaliphatic
groups, -
P03R17R18, -0P03R17R18, -S03R17, -0S03R17, -NR17R18, -SR17, -CN, -NO2, -CHO, -
CO2R17, and -CONR17R18, wherein R17 and R18 are each independently selected
from
H and (C1-C4) aliphatic groups; and Z is -0- or -S-;
comprising:
(1) glycosylating an alcohol or thiol having the formula:
CA 02738235 2014-04-01
- 3g -
HB 'h.
{ R13 Oir
PC-
R5
HB ' etkr4,,,
n Mit Age q R.7
Or
RI (CH2),,
1 r
R6'
R.5
HB
a an NPG"
R.4 (C142)
I
R6'
wherein B is S or 0, PG is acetyl or substituted acetyl and PG' is phthaloyl
or
substituted phthaloyl, with a glycosyl donor having the formula:
OM
Ac0 ClAc' 43-
'1"1-"...\..,..,õ
DT Atla -
AcCi .Nap.) , AcCi q
MPG'
CA 02738235 2015-01-05
- 3h -
wherein PG is acetyl or substituted acetyl and PG' is phthaloyl or substituted
phthaloyl, and Q is phthaloyl, substituted phthaloyl, Cl, Br, F, OAc, or
C(CCI3)=NH, in
the presence of a Lewis acid catalyst to give a 2-amino-2-deoxy-13-D-
glucopyranose
derivative having the formula:
A
=0 = 41-7.
Aca'......\...". X Kr irt
Ac0 -
NHPG
. .
V
'PG
OAc
, 5
Ac0,4 x
it ni -,õT fi re or,
NHPCI R.4 CO-Up
i
Rn'
0Ac
R5
AoD 0 1
ADO X . . n he NPG'
----...\,.......
NPGI R4 (CH-J.
I
RG
respectively
wherein B is S or 0;
(2) selectively deprotecting the 0-linked acetate groups present in the 2-
amino-2-
CA 02738235 2015-01-05
- 3i -
deoxy-p-D-glucopyranose derivative with ammonium hydroxide or sodium methoxide
in methanol;
(3) selectively 6-0-alkylating the resulting deacetylated derivative from step
(2) with
an alkyl halide in the presence of a tertiary amine to form a substituted
methyl,
substituted ethyl, benzyl or substituted benzyl ether;
(4) selectively deprotecting the PG or PG' groups with an alkali or diamine
base;
(5) simultaneously or sequentially tri-acylating the two amino groups and the
3-0H
position with an (R)-3-alkanoyloxyalkanoic acid or hydroxy-protected (R)-3-
hydroxyalkanoic acid in the presence of a peptide coupling reagent;
(6) introducing a phosphate group onto the 4-0H position with a
chlorophosphate or
phosphoramidite reagent to give a phosphotriester; and
(7) simultaneously or sequentially deprotecting the phosphate group, the 6-0-
alkyl
group, and any remaining protecting groups.
According to another aspect of the invention, there is provided a compound
having the formula:
CA 02738235 2014-04-01
=
Ho OH 0 x : - 3j - , .),....4N.
115
HO a ra til, I Bq
.ro
NHTrot; '
R4 (C112)r,
i
R4
wherein the subscripts n, m, p, and q are each independently an integer of
from 0 to
6; R4 and R5 are independently selected from H and methyl; PG is Aoc or Troc;
R6
and R7 are independently selected from H, OH, (C1-C4) oxyaliphatic groups, -
P03F12,
-0P03H2, -S03H, -0S03H, -NR15R16, _s¨K15, _
CN, -NO2, -CHO, -0O2R15,
-00NR15R16, -P03R15R16, _op03R15¨K16, _ SO3R15 and -0S03R15, wherein R15 and
R16
are each independently selected from H and (C1-C4) aliphatic groups.
According to a further aspect of the invention, there is provided a compound
having the formula:
air
, 0
WY .
Ho
NI-11,
N1-12
CA 02738235 2011-04-18
[00141 In another aspect this invention comprises a process comprising first
producing the
glycosyl halide as above, followed by reaction of the glycosyl halide with a
monosaccharide
in the presence of a silver salt to form a disaccharide.
[0015] Another aspect of this invention comprises a process for producing a
disaccharide
comprising reacting a monosaccharide with a silyl glycoside.
[0016] Yet another aspect of this invention comprises a process for silylation
of a
disaccharide and optionally for subsequently adding a phosphono side chain to
the
disaccharide.
[0017] A still further aspect of this invention comprises a process for
producing a
triacylated disaccharide from a disaccharide.
[0018] Yet another aspect of the invention is a process for removing an acetyl
protecting
group from a disaccharide.
[0019] Yet a further aspect of this invention comprises a process for
production of a
phosphorylated disaccharide by (a) selectively protecting the 6'-hydroxyl
substituent of a
disaccharide; and b) adding a phosphono side chain to the disaccharide at the
5'-position.
[0020] A still further aspect of this invention comprises a process for
simultaneously
removing all silyl-based protecting groups from a disaccharide having a
plurality of silyl-
based protecting groups.
[0021] Other aspects of this invention include other novel processes and novel
intermediates, and/or will be apparent from the description that follows.
DETAILED DESCRIPTION OF THE INVENTION
Definitions: as used herein:
100221 "Glycoside" refers to a tetrahydropyran ring bearing a substituent at
the 1-position
(i.e., at one of the carbon atoms adjacent to the oxygen atom in the ring)
that is a hydroxy,
optionally substituted alkoxy, or trisubstituted silyloxy group. Glycosides
may also contain
substituents at other positions, typically protected or unprotected hydroxy or
amino groups.
[0023] "Silyl glycoside" refers to a glycoside wherein the group attached at
the 1-position
is a trisubstituted silyloxy group such as a trimethylsilyloxy, tert-
butyldimethylsilyloxy, or
4
CA 02738235 2011-04-18
tert-butyldiphenylsilyloxy group. The silyl component of this group has the
formula
ReRbReSi, wherein Re, Rb, and Re are independently selected from the group
consisting of
Ci ¨ C6 alkyl, C3¨ C6 cycloalkyl, and optionally substituted phenyl.
Preferably one of the Ra,
Rb, and Re ?pups is larger than methyl; relatively hindered groups such as t-
butyl, phenyl,
and isopropyl are preferred. Included among the silyl components are
aryldialkylsilyl,
diarylalkylsilyl, and triaryisily1 groups. Typical examples include
triisopropylsilyl,
triphenylsilyl, t-butyldimethysilyl (TBS), and t-butyldiphenylsilyl (TBDPS)
groups. The silyl
component of the silyl glycoside is most preferably a TBS or TBDPS group.
[00241 The silyl glycoside can generally be represented by the formula (II)
wherein Rza is a trisubstituted silyl group, preferably TBS or TBDPS, and W,
X, Y, and Z
independently represent H, optionally protected hydroxy, optionally protected
amino, or
optionally substituted alkyl groups. Typically, Z represents an optionally
protected
hydroxymethyI group.
[0025) "Dihalomethvl alkyl ether" refers to a compound bearing an alkoxy group
and two
halogen atoms on a single carbon atom. Typical examples include
dic.hloromethyl methyl
ether (CHC120CH3), dichloromethyl ethyl ether (CHC130G2H5), dibromomethyl
methyl ether
(CliBr2OCH3), 1,1-dichloroethyl ethyl ether (CH3CC120C2H5), and the like.
Dichloromethyl
methyl ether is preferred in the processes of this invention.
[0026] "Glvcosyl halide" refers to a 2-halotetrahydropyran compound, for
example, 2-
chlorotetrahydropyran or 2-bromotetrahydropyran. The preferred halogens are
fluoride,
chloride, and bromide, with chloride being most preferred. In addition, the
glyeosyl halides
used in the processes of this invention will have other substitaents analogous
to those in
formula (II) above.
[00271 Glycosyl halides are generally represented by formula (DI):
au)
A
wherein W, X, Y and Z are as defined above for formula (II) and A is Cl, Br,
or F.
5
CA 02738235 2011-04-18
[0028] "Aliphatic" means a straight or branched chain, or non-aromatic
cyclical,
hydrocarbon radical, or combination thereof, which may be fully saturated, or
mono- or
polyunsaturated and can include di- and multivalent radicals, having the
number of carbon
atoms designated (i.e. C1-C10 means one to ten carbon atoms). Examples of
saturated acyclic
aliphatic groups (also termed "alkyl" groups) include, but are not limited to,
groups such as
methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, isobutyl, sec-butyl,
homologs and isomers
of, for example, n-pentyl, n-hexyl, n-heptyl, n-octyl, and the like. An
unsaturated aliphatic
group is one having one or more double bonds or triple bonds. Examples of
unsaturated
acyclic aliphatic groups include, but are not limited to, vinyl, 2-propenyl,
isopropenyl, crotyl,
2-isopentenyl, 2-(butadieny1), 2,4-pentadienyl, 3-(1,4-pentadienyl), ethynyl,
1- and 3-
propynyl, 3-butynyl, and the higher homologs and isomers. Examples of cyclical
aliphatic
groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl,
cyclopentenyl,
cyclohexenyl, cyclohexadianyl, and the like.
[0029] Divalent aliphatic groups include saturated and unsaturated groups
similar to those
mentioned above, for example methylene, -CH2-; ethylene, -CH2CH2-; n-butylene,
-CH2CH2CH2CH2-; and unsaturated groups such as -CHH-, -CH=CH-CH2CH2- and the
like.
[0030] The terms "oxyaliphatic", "aminoaliphatic" and "thioaliphatic" are used
in their
conventional sense, and refer to aliphatic groups attached to the remainder of
the molecule
via an oxygen atom, an amino group, or a sulfur atom, respectively. "Alkoxy",
"thioalkoxy"
and "aminoalkyl" refer to such groups containing saturated acyclic aliphatic
moieties.
[0031] The term "heteroaliphatic," by itself or in combination with another
term, means,
unless otherwise stated, a group analogous to an aliphatic group, i.e. a
saturated or
unsaturated straight or branched rktain, or cyclic, radical, or combinations
thereof, consisting
of the stated number of carbon atoms and further comprising at least one
heteroatom selected
from the group consisting of 0, N, Si and S, and wherein the nitrogen and
sulfur atoms may
optionally be oxidized and the nitrogen heteroatom may optionally be
quatemized. The
heteroatom(s) 0, N and S and Si may be placed at any interior position of the
heteroaliphatic
group or at the position at which that group is attached to the remainder of
the molecule.
Examples include, but are not limited to, -CH2-CH2-0-CH3, -CH2-CH2-NH-CH, -CH2-
C1-12-
N(C1-13)-CH3, -CH2-S-CH2-CH3, -CH2-CH2,-S(0)-CH3, -CH2-CH2-S(0)2-CH3, -CH=CH-0-
CH3, -Si(CH3)3, and -CH2-CH=N-OCH3.
6
CA 02738235 2011-04-18
[0032] Aliphatic groups may be substituted or unsubstituted. Substituents
include a variety
of groups selected from: -OR', =0, =NR', =N-OR', -Nita", -SR', -halogen, -
SiR'R"R?",
-0C(0)12.', -C(0)R', -CO2R', -CONR'R", -0C(0)NR'R", -NR"C(0)R', -NR'-
C(0)NR"R",
-NR"C(0)2R', -NR-C(NRR'R")=NR'", -NR'C(NR'R")=NR'",-NR-C(NR'R")=NR.'",
S(0)R', -S(0)2R', -S(0)2NR'R", -NRSO2R', -CN and -NO2 in a number ranging from
zero
to (2m'+1), where m' is the total number of carbon atoms in such radical. R',
R" and R"
each independently may be hydrogen, optionally substituted alkyl, aryl
optionally substituted
with 1-3 halogens, optionally substituted alkoxy, optionally substituted
thioalkoxy or '
optionally substituted aryl-(Ci-C4)alkyl groups. When a compound of the
invention includes
more than one R group, for.example, each of the R groups is independently
selected as are
each R', R." and R" groups when more than one of these groups is present. When
R' and R"
are attached to the same nitrogen atom, they can be combined with the nitrogen
atom to. form
a 5-, 6-, or 7-membered ring. For example, -NR'R" is meant to include I-
pyrrolidinyl and 4-
morpholinyl.
[0033] "Aromatic" or "md" refers to the typical substituted or unsubstituted
non-aliphatic
hydrocarbyl groups of this class, i.e., a polyunsaturated, typically aromatic,
hydrocarbon
substituent, which can be a single ring or multiple rings (up to three rings)
which are fused
together or linked covalently, such as phenyl, naphthyl, and the like.
[00341 "Arylalkyl" refers to alkyl groups subsisted by one or more aryl
groups; for
instance, benzyl, phenethyl, tiphenylmethyl, and the like.
[0035] "Acyl" refers to a group derived from an organic acid by removal of the
hydroxy
group. Acyl compounds may in general be aliphatic, aromatic or heterocyclic in
nature.
"Aliphatic acyl" refers to such groups derived from saturated or unsaturated
aliphatic acids,
and includes groups such as acetyl, propionyl, butyryl, hexanoyl, decanoyl,
dodecanoyl,
tetradecanoyl, and the like. In defining acyl groups by their carbon atom
content, the
reference is to the carbon atom content of the entire group. Thus, acetyl is a
C2 acyl group;
propionyl is a C3 acyl group, tetradecanoyl is a C14 acyl group, etc.
[0036] "Alkanoyloxycarbonyl" refers to groups having a saturated or
unsaturated aliphatic
group, or an arylalkyl group such as benzyl, linked through an oxygen atom to
a carbonyl
group, i.e. a group having the general formula Alk.-0C(0)- in which Alk.
stands for an
aliphatic or arylallcyl group as defined above.
7
CA 02738235 2011-04-18
[0037] " Alkanovloxyacyl" refers to a saturated or unsaturated acyl group
substituted at the
indicated position by an aliphatic group ALC(0)0- in which Al. stands for an
acyclic
saturated or unsaturated aliphatic group. The overall alkanoyloxy group
preferably has from 2
to 24 carbon atoms, most preferably from 6 to 14 carbon atoms. The acyl
portion of the
alkanoyloxyacyl group contains from 6 to 14 carbon atoms. A typical group of
this type is
the 3-(n-allcanoyloxy)acyl group, where the acyl group is tetradecanoyl and
the alkanoyloxy
group contains from 2 to 20, preferably from 6 to 14, carbon atoms, inclusive.
Similarly
"alkanoyl" refers to a group Al.C(0)- wherein Al. is as defied above.
[00381 "Protecting group" refers to any of a large number of groups used to
replace one or
both hydrogens of a reactive group such as a hydroxy, amino or tlaiol group,
so as to block,
prevent, or reduce reactivity of the group. Examples of protecting groups (and
a listing of
commonly used abbreviations for them) can be found in T. W. Greene and P. G.
Puts,
"Protective Groups in Organic Chemistry" (Wiley), Beaucage and Iyer,
Tetrahedron
48:2223 (1992) and Harrison et al., Compendium of Synthetic Organic Methods,
vols. 1-8
(Wiley).
[0039] Representative amino protecting groups include those that form a
carbamate or
amide with the nitrogen atom, as well as those groups collectively referred to
in the Greene
and Puts text as "special -NH protective groups". Representative examples of
amino
protecting groups include acetyl (Ac), tdfluoroacetyl, benzyloxycarbonyl
(Cbz), tert.-
butoxycarbonyl (Boc), allyloxycarbonyl (Mc), 9-fluorenylmethyloxy-carbonyl
(Fmoc),
nitro-versatryloxycarbonyl (Nvoc), optionally substituted phthaloyl and the
like.
[0040] Representative hydroxy protecting groups include those where the
hydroxy group
is either acylated or alkylated, such as by the formation of ethers or esters
using, for instance,
acetyl, benzyl, trityl, alkyl, tetrahydropyranyl, allyl and trisubstituted
silyl groups.
[00411 The choice of a protecting group for a given compound, purpose or set
of
conditions is within the skill of those in the art, and is done so as to
protect, generally or
selectively, the reactive group in question under the prevailing conditions
(presence of other
reactive compounds, pH, temperature, etc.) Protecting groups that may be used
in this
invention and are mentioned herein include phthaloyl, acetyl (Ac), benzyl
(Bn), 2,2,2-
trichloroethoxycarbonyl (Troc), 1-butyldimethylsily1 (TBS), t-
butyldiphenylsily1 (TBDPS),
and 2,2,2-trichloro-1,1-dimethylethyl chloroformyl (TCBOC) groups. As is known
in the art,
a certain protecting group or type of group may be more suitable than others
for use with a
8 =
CA 02738235 2011-04-18
particular compound or in a given situation, and advantage is taken of these
suitahilities in
developing processes that involve compounds with reactive groups such as
hydroxy andkr
amino. Thus, as will be seen below, a reaction scheme can be developed for
producing or
reacting certain compounds in which general or selective protection or
deprotection (removal
of protecting groups) is carried out at certain points. For instance, in order
to selectively react
a hydroxy group in a compound that also contains an amino group, or vice
versa, the group
whose reaction is not desired at this point can be blocked with a protecting
group that is not
removed under conditions of the reaction (for example, is not base-
hydrolyzable if the
reaction is to be conducted under basic conditions, while the group to be
reacted can be
protected by a group that is base-hydrolyzable, so that said group becomes
unblocked, and
thus reactive, at that time. Similarly as will be seen below, in order to
selectively react a
group, e.g., a hydroxyl group, located at one position in the molecule, it may
be protected
with a different protecting group than other hydroxyls in the molecule. As
used herein, the
designation "PG" refers to protecting groups that form esters, ethers or
carbonates with
hydroxy groups (i.e., with the oxygen atom of a hydroxy group] or that form
amides or
carbamates with amino groups [i.e. with the nitrogen atom of an amino group.
The
designation t' PG' "is used herein to refer to optionally substituted
phthaloyl groups, for
= example phthaloyl or tetrachlorophthaloyl, and which may be used to
protect an amino group,
as shown. However, in any event, the selection of particular protecting groups
used or
illustrated in the processes described herein is not in any way intended to
limit the invention.
The major products
[0042] The major products produced using the processes and intermediates of
this
invention comprise a group of compounds that include both AGP compounds, which
are
mono-saccharides, and disaccharides of somewhat analogous structure. In
general, the
products can be depicted by the formulas (1) and (1 a -c):
OR9
R90
NH
R10 ¨
?./
R20
(CH2),CH3 (CHACHs
9
CA 02738235 2011-04-18
Cl)
and pharmaceutically acceptable salts and derivatives thereof, wherein Y is -0-
or ¨NH-;
and R2 are each independently selected from saturated and unsaturated (C2-C24)
aliphatic
acyl groups; R8 is -H or ¨P03R11R12, wherein R11 and R12 are each
independently ¨H or (C1-
C4) aliphatic groups; R? is ¨H, -CH3 or -P03R13R14, wherein R13 and R14 are
each
independently selected from ¨H and (C1-C4) aliphatic groups; and wherein at
least one of R8
and R9 is a phosphorus-containing group, but R8 and R9 are not both phosphorus-
containing
groups; and X is a group selected from the formulae:
1--10
HO 0
R5 p R13
NH Rio q'
R4
(CH2)P
OR3 and
R110
12120
(CH2)rCH3 (CH2)rCH3 ( H2),CH3
(La) (1b) (lc)
wherein the subscripts n, m, p, q, n', m', p' and q' are each independently an
integer of from 0 to 6, provided that the sum of p' and m' is an integer from
0 to 6; the
subscript r is independently an integer of from 0 to 14 and may be the same or
different; R3,
and R12 are independently saturated or unsaturated aliphatic (C2-C24) acyl
groups; and
when X is formula (1a) or (1c) one of RI, R2, R3, R11 and R12 is optionally
hydrogen; R4 and
R.5 are independently selected from H and methyl; R6 and R7 are independently
selected from
1-1, OH, (C1-C4) oxyaliphatic groups, -P03H2, -0P03H2, -S03H, -0S0311, -
NR Rits,
CN, -NO2, -CHO, -CO2R15, -CONR15R16, -P03R15R16, -0P03R15R16, -SO3R15 and -
0S03R15,
wherein R15 and R16 are each independently selected from H and (C1-C4)
aliphatic groups;
RI is selected from H, CH3, -P031-12, co-phosphonooxy(C2-C24)allcyl, and w-
carboxy(C1-
C24)alkyl; R13 is independently selected from H, OH, (C1-C4) oxyaliphatic
groups, -
po3RpRi8, _opo3Rt7Ri8, _s03-17, _
OSO3R17, -NRI7R18, -SR17, -CN, -NO2, -CHO, -0O2R17,
and -CONR17R18, wherein RI7 and R18 are each independently selected from H and
(C1-C4)
aliphatic groups; and 2 is ¨0- or ¨S-.
CA 02738235 2011-04-18
The processes and intermediates
[0043] One process of this invention comprises the production of glycosyl
halides that
comprises reacting an 0-silyl glycoside with a dllialomethyl alkyl ether in
the presence of
zinc chloride, zinc bromide, boron trifluoride, or a similar Lewis acid. More
specifically, in
this process, a glycosyl halide is formed by reacting a silyl glycoside having
the formula (PO:
wherein R20 is a trisubstituted silyl group having the formula RaRbR.Si in
which R., Rb and
R. are independently selected from the group consisting of C1-C6 alkyl, C3-C6
cycloalkyl and
optionally substituted phenyl, preferably TBS or TBDPS, and W, X, Y, and Z
independently
represent H, optionally protected hydroxy, optionally protected amino, and
optionally
substituted alkyl groups, with a dihalomethyl alkyl ether, preferably
dichloromethyl methyl
ether, in the presence of zinc chloride, zinc bromide, boron trifluoride, or a
similarly suitable
Lewis acid. The Lewis acid is used in about a stoichiometric amount with
respect to the silyl
glycoside. The reaction to produce the glycosyl halide is conducted at a
temperature of from
about -30 C to about 50 C, preferably from about 0 C to about 30 C, and in
the presence of
a solvent such as chloroform, dichloromethane, dichloroethane, or similar
solvents that are
inert to the conditions required for the reaction. The temperature of the
reaction is selected to
allow the reactants to substantially dissolve and to prevent the dihalomethyl
alkyl ether from
boiling away. Yields of the desired product glycosyl halide are generally from
about 50 to
about 95%. Selection of such solvents is within the knowledge of those of
ordinary skill in
the art. The silyl glycosides are produced conventionally, typically in a
protected form, as is
known in the art. However, certain silyl glycosides, such as certain
triacetylated silyl
glycosides and derivatives thereof; may be produced via novel intermediates
described
below, which form an aspect of the invention.
[0044] One of skill in the art will appreciate that the glycosyl halides may
exist as isomers
if other substituents are present on the glycosyl halide ring. The invention
includes
production of the separate isomers as well as mixtures of both isomers.
Conditions for
reactions of many nucleophiles with glycosyl halides are well known to persons
of ordinary
skill in the art.
[0045] The resulting glycosyl halides thus typically have the formula (1)1)
11
CA 02738235 2011-04-18
010
A
wherein A is Cl, Br, or F and W, X, Y and Z are as defined above.
[00461 In one preferred embodiment, the silyl glycoside and resulting products
are
substituted at the 3- position (substituent X) by an aliphatic acyl group,
preferably an
alkanoyloxyacyl group, more preferably a 3-n-alkanoyloxyacyl group, and most
preferably a
3-alkanoyloxytetradecanoyl group, in which the aliphatic or alkanoyl group
contains from 2
to 24, preferably from 2 to 18, and most preferably from 6 to 14, carbon
atoms, and the
protecting groups in the compound in question are preferably Troc groups or
similar
alkanoyloxycarbonyl groups. In such embodiments the compounds have the general
formula
(IV) or (V):
OTroc
Ru0
NH
Troc (IV)
OTroc
Troc0 0
R21..`"==\
NH
TrocA (v)
wherein A is Cl, Br, or F; R20 is a trisubstituted silyl group and R21 is an
aliphatic acyl group, preferably a 3-n-alkanoyloxytetradecanoyl group. Note
that in this
formula and those that follow, protecting groups have been specifically
identified for
purposes of illustration and/or clarity. However, as known in the art, other
protecting groups
as defined generally above for "PG" may be used, as suitable. Thus, for
instance, more
generally these compounds can be represented by the formula
0-PG
PG-0 0
R210
NH
PGA(J)
where PG represents protecting groups that form an ether, ester or carbonate
with the
oxygen atom or that form an amide or carbamate with the nitrogen atom,
respectively.
12
CA 02738235 2011-04-18
[0047] In another preferred embodiment, the silyl glycoside has a hydroxyl
group at the 4-
position substituted with a phosphate ester group such as a dialkylphosphonyl
or
diarylphosphon.y1 group, R21 is an alkanoyloxyacyl group, preferably a 3-n-
.
allcanoyloxytetradecanoyl group, and the protecting groups are preferably
"TCBOC" groups,
obtained from 2,2,2-trichloro-1,1-dimethylethyl chloroformate, or similar
alkanoyloxycarbonyl protecting groups such as Troc; i.e., the silyl glycoside
may have the
specific formula (VI):
OTCBOC
(8220)2130 OR20
R23.0
!Prix (V.1)'
wherein R20 is a trisubstituted silyl group, preferably TBS or TBDPS; R21 is
an
aliphatic acyl, preferably an alkanoyloxyacyl, group; and Rn is alkyl, aryl,
or arylalkyI, or
may have a more general formula which allows for the use of other suitable
protecting
groups,
and the glycosyl halide correspondingly has the more specific formula (VII):
vOTCBOC
9 0
(R220)2P0
R211.1
TrocA (vi)
wherein R21 and R22 are as defined above and A is Cl, Br, or F.
[0048] In one aspect of the invention the glycosyl chlorides thus produced are
reacted with
a monosaccharide, preferably in the presence of a silver salt, to produce a
disaccharide by this
two-step process. Monosaccharides that may be used as reactants in this
process include, for
example, those having the formulas (i)-(iii):
OH
HO OBn
TBSO
NH
Troc
(ii):
13
CA 02738235 2011-04-18
OH
HO OBn
TBSO
NH
R23
or
e...OH
Troc0
R23
wherein R23 is an aliphatic acyl group, preferably a 3-n-
alkanoyloxytetradecanoyl group, as described above.
[0049] Disaccharides that can be produced by such processes include those
having the
formulas (iA)-(ivA):
(iA):
OAc
Ac0
Tnx TBSO
NH
Troc
(iiA):
OTroc
0
Troc0 0
R210
NH HO OBn
Troc
NH
Troc
(iiiA):
0
Troc0 0
R230
NH Ho OBn
Tnx TBS
NH
R23
14
CA 02738235 2011-04-18
=
or
(ivA):
OTCBOC
9 0
(R2a0)2P0
R210 0
NH Ho OBn
Troc Two
NH
R23
wherein R21, R22 and R23 are as defined above, and the indicated protecting
groups are exemplary of those that may be used.
100501 Reactions to produce products (iA) -(ivA) according to this invention
are generally
conducted at a temperature of from about ¨30 C to about 30 C, in a
chlorinated or other
solvent in the presence of a silver catalyst such as silver
trifluoromethanesulfonate (triflate)
and under anhydrous conditions, with or without other additives such as
molecular sieves or
buffering agents such as tetramethylurea..
[0051] In another aspect of the invention the silyl glycosides of Formula (R)
are coupled
with a monosacchmide directly, without proceeding through formation of a
glycosyl halide.
The resulting product is again a disaccharide having substituems according to
the starting
materials. Such a process is generally conducted at a temperature of from
about ¨78 C to
about 50 C in the presence of a suitable Lewis acid catalyst such as
trimeth.ylsilyltriflate of
boron trifluoride etherate with or without the addition of drying or buffering
agents. In
another aspect of this invention protecting groups can in effect be removed
from a silyi
glycoside having such groups by reacting it with a dthaloalkyl ether- to
produce the glycosyl
halide, and then reacting the glycosyl halide with a silver salt such as
silver oxide or silver
carbonate in the presence of water to produce the corresponding hemiacetal.
[0052] The disaccharides produced by either process may be further reacted by
silylating
the hydroxyl group at the 4-position of the reducing sugar with a silylating
group such as
TBS in the presence of imidazole and N,N-dimethylformaraide to produce a 3,4-
bis-silylated
compound. Addition of a phosphate group in the 4-position of the non-reducing
sugar is
then achieved by a sequence of steps involving (1) deprotection of the 4,6
protecting groups
(typically acetate or Troc), (2) N-deprotection/acylation, (3) selective
protection of the
CA 02738235 2011-04-18
primary 6-position with a group such as TCBOC, and (4) by reacting the 6-
protected
disaccharide with a phosphonylating agent such as a phosphoramidite reagent,
e.g., dibenzyl
dfisopropylphosphoramidite [providing a dibenzy.lphosphono side chain], or a
chlorophosphate such as bis(2,2,2-trichloroethyl)chlorophosphate [providing a
bis(2,2,2-
trichloroethyl)phosphono side chain] or diphenyl chlorophosphate [providing a
.diphenylphosphono side chain].
[0053] The invention also, analogously, includes processes for the production
of
triacylated disaccharides such as those having the formula (VIII):
o =sac
(R22(3)2Po
R21
TBSO OBn
= R24 'Imo
NH
R23 (\7111)
wherein R21, R23 and R24 are aliphatic acyl, preferably alkanoyloxyacyl,
groups, and Rnis an optionally substituted alkyl, aryl, or arylalkyl group, by
selectively
protecting the C-6 hydroxyl group of a corresponding disaccharide with 2,2,2-
tdchloro-1,1-
dimethylethyl chloroformate in the presence of a tertiary amine such as
pyridine. Preferably,
R32, R23 and R24 are (R)-3-hexadecanoyloxytetradecanoyl, (R)-3-
octadecanoyloxytetradecanoyl, and (R)-3-tetradecanoyloxytetradecanoyl,
respectively, but
they can be the same or different depending on the desired substitutions and
nature of the
monosaccharide donor used in the glycosylation step.
[0054] This invention also relates to processes for producing aminoalkyl and
cyclic
aminoalkyl glucosamim¨de (AGP) compounds, that is compounds of formula (I) in
which Xis
(a) or (1c), in which both the fatty acid and the phosphate groups are
introduced onto the
AGP backbone after the initial glycosylation (coupling) step. These processes
involve the
use of novel glycoside triol intermediates which can be selectively protected
in the sugar 6-
position prior to the introduction of the ester- and amide-linked acyloxyacyl
residues.
[0055] One preferred method of the invention for preparing AG? compounds is
shown in
Scheme 1 below. Scheme 1 depicts the production of specific compounds of
Formula (la)
but is intended to serve only as an example of this aspect of the invention,
as the same or a
similar process could be used to produce other compounds of the type of
Formula (1a) as well
as compounds of Formula (Ic).
16
CA 02738235 2011-04-18
[0056] In this process introduction of the aliphatic acyl, e.g. (R)-3-n-
alkanoyloxy-
tetradecanoyl, and phosphate groups into the glucosamirte and aglycon units is
also
performed subsequent to the coupling reaction but, in contrast to the method
shown in the
prior art patents, the 3-hydroxyl group is selectively esterified with an
alkanoic acid
substituted by an aliphatic acyl group, preferably an (R)-3-n-
alkanoyIoxyalkanoic acid, in the
presence of an unprotected/tmphosphorylated 4-hydroxyl giiiup with the 6-
position blocked.
This is achieved by protecting the 6-hydroxyl group of the sugar unit with a
persistent
protecting group in lieu of temporary protection of the 4,6-hydroxyl positions
with an
acetonide. Preferably, j3-glycoside 8 or the corresponding bis-Troc derivative
9, is de-0-
a.cetylated with a suitable base to give a triol intermediate 10, which is
selectively protected
on the 6-position with a hindered sily1 group such as t-butyldimethylsilyl
(TBS) under
standard conditions known in the art to give silyl-protected intermediate 12.
The triol
intermediate 10 is a novel compound 3-0-Acylation of 12 with (R)-3-n-
alkanoyloxytetradecanoic acid, for instance, followed by
deprotection/acylation of the sugar
and aglycon amino groups, simultaneously (PG=Troc) or sequentially (PG=Aoc),
using either
zinc (PG=Troc) or zinc and Pd(0) (PG=Aoc) in the deprote,ction step and (R)-3-
n-
alkanoyloxytetradecanoic acid in the acylation step, provides hexaacylated
intermediate 13.
Pentaacylated compounds, i.e. in which one of the acyl groups R2, R3, R11
or R12 is
hydrogen, can be prepared by utilizing different protecting groups for the two
amino groups
so that one or the other can be selectively acylated; for instance, using an
Aoc group for one
and a Troc group for the other.
[00571 Phosphorylation of the 4-hydroxyl group is carried out by methods known
in the art
using preferably either a dibenzyl or di-t-butyl protected ch1orophosphate or
phosphoramidite
reagent to give the phosphotziester 14. The phosphate, silyl and any remaining
protecting
groups in 14 are then cleaved under mildly acidic conditions or by other
appropriate means to
give compounds of Formula (Ia). It is important to note that the order in
which the phosphate
and N-linked (R)-3-n-alkanoyloxytetradectmoyl groups in 14 are introduced can
be reversed
by the appropriate selection of orthogonal phosphate and amine protecting
groups.
[0058] A variant of the method shown in Scheme 1 is shown in Scheme 2 and
involves the
use of a commercially available glycosyl donor such as 15 possessing either
acetyl or
phthalimide nitrogen-protecting groups and either an anomeric acetoxy or
halide group.
Again, this Scheme is representative of processes of the invention for
producing compounds
of Formula (Ia) or (Ic).
17
CA 02738235 2011-04-18
[0059] In Scheme 2, glycosyl donor 15 is coupled with a similarly N-protected
acceptor
unit 16 in the presence of a suitable catalyst to give 0-glycoside 17. Since N-
acetyl and
phthalimide groups typically require strongly basic conditions for
deprotection, the use of a
base-stable ether-linked protecting group such as triphenylmethyl (trityl, Tr)
on the 6-position
is generally required. Accordingly, de-O-acetylation of 17 under standard
conditions
followed preferably by selective tritylation of the 6-position gives diol 18.
= Base-induced
cleavage of the N-acetyl or phthalirnide groups followed by simultaneous or
sequential N-
and 0-acylation of the resulting diamino diol intermediate with an (R)-3-n-
alkanoyloxytetradecanoic acid in the presence of suitable coupling reagent(s)
affords the
hexaacylated derivative 19. The diamino diol intermediate formed by treating
compound 18
with base has the formula:
OTr
HO
NH2
Phosphorylation of 19 with a chlorophosphate or phosphoramidite reagent as in
Scheme 1
followed by deprotection under mildly acidic conditions or by other
appropriate means gives
compounds of Formula (La).
18
CA 02738235 2011-04-18
_
SCHEME 1 .
OAc
Ac0A00 x
---.0\1........\.......... Rs
----..----4-4-N A- R7 NH4OH, Me0H
_________________________________________________ al,
NHTroc PG
R4 (C112.)p
I
8 PG=Aoc R6
9 PG=Troc -
OH
Rs
.......õx TBS-CI, base
HO is'N'ie".*,n NA R7
NHTroc PG
. R4 (CHip
PG=Aoc or Trot R6
OTBS
1. 4 R=R
HO
x
--....00\ii......\,...... Rs
1
2. Pd(0) and/or Zn in
3.4 R=R2or R3
NHTroc PG
R4 (CH)p
R6
12 PG=Aoc or Troc
OTBS
Rs
7Ek
n ni N q Ri benzyl phosphoramidite
0 NH
R4 (CH2)p 0 or (Bn0)2P(0)0, bas:
R1C, 1
R20R6 nnOR3
n-Cii.H23
n-0O23 n-CLiH23
13
OTBS
0
(Bn0)2(0)P0 X
0 cl R7
0
1
NH Y n L')5An A'k aa)
0 R4 (CHOp 0
RIO I
R20 R6 iiiioR3
n-con
n-con n-CE.H23
14
19
CA 02738235 2011-04-18
,
SCHEME 2
OAc
Rs
Ac0
..--0100\b06...\...... + )1X IY.(in NAR7 catB" I.
Ac0 PG
NHPG 4:2 Rs (C1-I 2)p
15 PG=Ac or Phth R6
Q=ballde, OAc, etc 16 PORAc or Phth
'
125
Ac0".1...\........x,y4N....4R7 Me0Na, Me0H
Ac0 ____________________________________ r
NHPG PG
R4 (CH2)p
I
17 R6
......1DH=\46....\...........
HO 0 Rs Tr-CI, base
HO a
X t..)AN"...OrNAR7 _________________________________
NHPG PG
Ri (12)p
17a R6
4r
Aµkq
n m N R7 1. base
NHPG PG _______________ ,
R4 (012)p 2.4 RoltecR2wR3
= I
Rs
18
0Ø....\l'r õ,.......
HO 0
0 X
0 NH
R4 (CH2)p 0
Ra0 I
Rs ono%
n-C13,1123R20
n-C11H23 ri-CiiH23
19
In the above Schemes I and 2 the various groups R1-1t7, n, p and q are as
defmed above.
CA 02738235 2011-04-18
ROW The
invention is further illustrated by the examples that follow. These examples
are presented solely as illustrative of the invention and do not in any way
limit its definition
or scope.
Example 1: Production of 2-Deoxv-4-0-diphenviphosphono-3-04(R1-3-
tetradecanovloxytetradecanov11-6-042,2,2-trichloro-1.1-dimethylethoxycarbonvi)-
2-
(2.2.2-trichloroethoxvcarbonvlamino)-a-D-aluco-pyranosv1 Chloride
[0061] This process is depicted in scheme A, below, and includes novel
intermediates (iv),
(vi) and (vii), which comprise aspects of this invention.
21
CA 02738235 2011-04-18
Scherng A
HO./..x. Oix0H Ac0 0 OTBDPS
. --0.- ----0.
HO NH2 Ac0 NHTroc
OH OAc
V iv
x0x OTBDPS 0 0 OTBDPS
i
Ac0 NHTroc
.......
"....... 6........Ø.. .1).......
0 NI1Troc
OAc OH
vi
0 0 CI
TCBOCO OTBDPS. TCBOCO
------i-
0NHTroc ---0- (C6H50)2(0)P NHTroc
....õ..
(C81-150)2(0)P
0..,..r........r.CiiHz3 0......r.,rc1
11-123
0 0)(C131127 0
0,....r0131127
0
0
vii viii
(a) Production of t-Butyldiphenylsilyl 2-Deoxy-4.6-0-isopropylidene-2-(2,2.2-
tricbloroethcegcarbonylamingl-a-D-glucouyranoside (Scheme A. compound vi).
[00621 (1) 2,2,2-Trichloroethorycarbonyl chloride (200 g, 0.944 mol) is added
portionwise to a solution of D-glucosamine hydrochloride (r, 200 g, 0.927 mol)
and NaHCO3
(200 g, 2.4 mol) in water (4 L) in a 10 L 3-neck round-bottom flask and the
resulting mixture
is mechanically stirred overnight at room temperature. The white precipitate
that forms is
collected by filtration using a 2 L fitted funnel, washed with ether (2 L),
and dried at high
22
CA 02738235 2011-04-18
vacuum for 3 hours to give 297 g (90%) of 2-deoxy-2-(2,2,2-
trichloroethoxycarbonylamino)-
D-gIucose as a white solid (MW 354.57).
[0063) (2) A solution of 2-deoxy-2-(2,2,2-hichloroethoxycarbonylamino)-D-
glucose (297
g, 0.838 mol) obtained in (1) above in a mixture of pyridine (1 L, 12.4 mol)
and acetic
anhydride (1 L, 10.6 mol) in a 10 L round-bottom flask is mechanically stirred
at room
temperature overnight. The reaction mixture is concentrated under reduced
pressure to give
an oil which is azeotroped with toluene (2 x 1L) and dried at high vacuum
overnight to give
438 g (-100%; 90% from y.) of the tetraacetate as a syrup (MW 522.71, TLC
(Et0Ac) RI
0.75).
[00641 (3) The tetraacetate obtained in (2) above (438 g, 0.838 mol) is
dissolved in Et0Ac
(4 L) and transferred to a 10 L 3-neck round-bottom flask, treated with
morpholine (200 mLõ
2.29 mol), and mechanically stirred for 8 hours at room temperature. Reaction
completion
determined by TLC (50% Et0Ac/hexanes). 3 N aq HC1 (2 L) is added and the
resulting
= mixture is stirred for 30 minutes. The mixture is transferred to a 6 L
separatory funnel and the
layers are separated. The organic phase is washed with saturated aq NaC1 (1
L), dried
(Na2SO4), and concentrated to give 373 g (93%, 84% from y). of the 1-0-
deprotected
derivative (hemiacetal) as a white foam (MW 480.67; TLC (50% Et0Ac/hexanes) RI
0.22).
[00651 (4) A solution of hemiacetal obtained in (3) above (373 g, 0.776 mol)
and
imidazole (132 g, 1.94 mol) in N,N-dimethylfonnamide (DMF, 430 mL, 1.8 M) is
treated
with t-butylchlorodiphenylsilane (242 mL, 0.931 mol), and stirred for 48 hours
at room
temperature. Reaction completion is confirmed by TLC (50% Et0Ac/hexanes). The
reaction
mixture is partitioned between ethyl ether (4 L) and water (1 L) in a 6 L
separatory funnel
and the layers separated. The ether layer is washed with water (1L), dried
(Na2SO4), and
concentrated to give a bronze-colored oil which is crystallized from Et0Ac-
hexanes (-4:2
v/v) in three crops to provide 474 g (85%, 71% from ir) of the t-
butyldiphenylsilyl glycoside
iv as a white solid (MW 719.08; TLC (50% Et0Ac/hexanes) RI 0.44).
100661 (5) A solution of the silyl glycoside obtained in (4) above (474 g,
0.659 mol) in
Me0H (2 L) in a 3 L 3-neck round-bottom flask is treated with ammonium
hydroxide (300
mL, 4.5 mol) (some precipitation occurs) and stirred at room temperature
overnight, and then
heated with a second portion of ammonium. hydroxide (50 ml.,, 0.75 mol) and
again stirred
overnight. Reaction completion is determined by TLC (Et0Ac). The reaction
mixture is
concentrated and the resulting residue is dissolved in Et0Ac (500 mL), placed
on a pad. of
23
CA 02738235 2011-04-18
silica gel (1 kg) in a 3 L flitted glass funnel, and elated with 50% Et0Ac-
hexanes (5 L) and
Et0Ac (7 L). The fractions containing the product are concentrated in a 3 L
round-bottom
flask to give 329 g (84%, 60% from y) of the triol (MW 592.97, TLC (Et0Ac)
R10.35).
[0067] (6) A slurry of the triol obtained in (5) above (329 g, 0355 mol) in
2,2-
dimethoxypropane (1.5 L) in a 3 L round-bottom flaRk is treated with
camphorsulfonic acid
(6.4 g, 0.028 mol) and magnetically stirred at room temperature overnight,
giving a light
yellow solution. Solid NaHCO3 (4.6 g, 0.055 mol) is added and the resulting
mixture is
stirred for 2 hours at room temperature and then concentrated to dryness. The
crude product
obtained is dissolved in dichloromethane (1.2 L), divided into two equal
portions, and placed
on silica gel (1 kg, pre-wetted with 30% Et0Ac/hexanes) in two separate 3 L
flitted glass
funnels, and elated with 30% Et0Ac/hexanes (10 L) and 50% Et0Ac/hexanes (8 L).
Fractions containing purified product are combined and concentrated to give
compound vi as
an amorphous solid. The product can be further purified by crystallization
from hexanes, if
necessary.
Molecular Formula: C23}136C13NO7Si
Molecular Weight 633.04
Theoretical Yield: 587 g (based on y)
Expected Yield: 306 g (87%, 52% from y)
TLC: Rf 0.60 (Et0Ac)
(b) Production of t-Butyldiphenvlsilyl 2-Deoxy-4-0-diphenylphosphono-3-0-1(R)-
3-
tetradecanoyloxytetradecanoy11-6-0-(2.2.2-trichloro-1,1-
dimethylethoxycarbonv1)-2-(2,2,2-
trichloroethoxycarbonylaminol-a-D-gluconyranoside (Scheme A, compound vii).
[0068] (1) A solution of compound yj (141 g, 0223 mol) in. CH2C12 (1 L) in a 2
L round-
bottom flask is treated with 3-(R)-(tetradecanoyloxy)tetradecanoic acid (101.7
g, 0.224 mol),
DCC (55 g, as a melt, 0.267 mol) and 4-pyrrolidinopyridine (3.3 g, 0.022 mol),
and stirred at
room temperature overnight Reaction completion is determined by TLC (20%
Et0Adhexanes). The reaction mixture is filtered, concentrated to ca. one-
hnlfvolume,
divided into two equal portions, and placed on silica gel (1 kg, pre-wetted
with 2.5%
Et0Ac/hexanes) in two separate 3 L flitted glass funnels. Gradient elution
with 2.5%, 5%,
and 10% Et0Ac/hexanes (8 L each) and concentration of the fractions containing
the product
in a 3 L round-bottom flask gives 220 g (92%) of the ester (MW 1069.72, TLC
(20%
Et0Adhexanes) Rf 033).
24
CA 02738235 2011-04-18
[0069] (2) The ester obtained in (1) above (218 g, 0.204 mol) is suspended in
90% aq
AcOH (1 L) in a 3 L round-bottom flask and stirred (on rotary evaporator) at
70 C for 2.5
hours, giving a milky solution. Reaction completion is determined by TLC (20%
Et0Ac/hexanes). Th6 reaction mixture is concentrated and residual AcOH is
removed
szeotropically with toluene (2 x 500 mL). The crude product obtained is
dissolved in 10%
Et0Adhexanes (400 mL), divided into two equal portions, and placed on silica
gel (1 kg) in
two separate 3 L fitted glass funnels. Gradient elution with 10% Et0Ac/hexanes
(10 L) and
15%, 20%, and 30% Et0Ac/hexanes (5 L each) and concentration of the fractions
containing
the product gives 193 g (92%, 85% from Li) of the diol (MW 1029.66, TLC (20%
Et0Ac) RI
0.10) containing a small amount (<5% by TLC) of 6-0-acetyl by-product (RI
0.25). (Note:
The 6-acetate by-product is readily separated by radial compression
chromatography as the 4.
diphenylphosphate derivative in step (3) below.)
[00701 (3) A magnetically stirred solution of the diol obtained in (2) above
(193 g, 0.187
mol) in CH2Cl2 (1 L) at 0 C is treated with pyridine (18.2 mL, 0.225 mol)
followed by 1,1-
dimethy1-2,2,2-trichloroethyl chloroframate (49.5 g, 0.206 mol). Progress of
the reaction is
monitored by TLC (20% Et0Ac/hexanes). Once the reaction is completed by TLC
(typically
30-60 minutes, but longer reaction times may be required), triethylamine (55
mL, 0.39 mol),
4-pyrrolidinopyridine (13.9 g, 0.094 mol), and diphenyl chlorophosphate (58.2
mL, 0.281
mol), are added sequentially and the resulting mixture is stirred at room
temperature
overnight. Reaction completion is determined by TLC (20% Et0Ac/hexanes). The
reaction
mixture is concentrated to dryness and the residue obtained is partitioned
between Et0Ac
(1.5 L) and 1.2 N aq HC1 (2 L) in a 6 L separatory funnel and the layers
separated. The
Et0Ac layer is washed with water (2 L), dried (Na2SO4), and concentrated. The
residue
obtained is dissolved in 10% Et0Ac/hexa.nes (500 mL) and purified by gradient
elution on a
Biotage 150 Hi system (150L column) with 10% Et0Adhexanes (50 L), collecting
950 mL
fractions. The fractions containing compound vii are combined and
concentrated.
Molecular Formula: C70H95CI6NO15ni
Molecular Weight: 1465.30
Theoretical Yield: 326.8 g (based on yl)
Expected Yield: 211 g (77%, 65% from y_i)
TLC: RI 0.47(20% Et0Actexanes)
CA 02738235 2011-04-18
(e) Production of 2-Deoxy-4-0-diphenylphosphono-3-0-YRI-3-tetradecanoyloxy-
tetradecanoy13-6-0-(2.2.2-trichloro-1.1-dimethylethoxycarbony1)-2-(272,2-
trichloroethoxycarbonylamino)-a-D-glocopyranosyl Chloride (scheme A.. compound
viii).
[0071] A solution of compound vii (192 g, 0.131 mol) in CHCI3 (2 L) at 0 C in
a 5 L
round-bottom flask is treated with oe,ot-dichloromethyl methyl ether (78 mL,
0.87 mol),
followed by ZnCl2 (1.0 M in ether, 100 ml., 0.1 mol) dropwise via an addition
funnel. The
cold bath is removed and the resulting mixture is stirred at room temperature
overnight.
Reaction completion is determined by TLC (20% Et0Ac/hexanes). The reaction
mixture is
treated with cold saturated aq NaHCO3 (1 L), stirred for 1 hour, and the
layers are separated
in a 6 L separatory funnel. The organic layer is dried (MgSO4) and
concentrated. The residue
obtained is purified on a Biotage 150 Hi system (150L column) eluting with 10%
Et0Ac/hexanes (80 L, 950 ml. fractions). The fractions containing pure product
are
combined and concentrated.
Molecular Foimula: C34H79C17N0I4P
Molecular Weight: 1245.36
Theoretical Yield: 163.2 g
Expected Yield: 141 g (86%)
TLC: Rf 0.42 (20% Et0Ac/hexanes)
Example 2¨ Preparation of (N-11R1-3-Decanovloxvtetradecanov11-042-deoxv-4-0-
phosphono-24(R)-3-decanovlorytetradecanovlaminol-3-0-1(R)-3- -
decanovloxytetradecanov11-B-D-glueopyranosv11-L-serine Triethvlammonium Salt
[a
compound of Formula (Ia) in which RI=R2=R3=n-C9H13CO, Z=Y=0, n=nr=p=q=0, 1=10,
R4=Rs=R7=R9=1-1, R6=CO2H, Rs=P03H2A, namely
26
CA 02738235 2011-04-18
JOH
CO2H
H203P0-0
NH
0 NH
0
0
00
0110 0
ol
[0072] This example utilizes a process as shown in Scheme 1.
[0073] (1) A solution of 1,3,4,6-tetra-0-acety1-2-deoxy-2-(2,2,2-
trichloroethoxy-
carhonylamino)-13-D-glucopyranoside (5.33g, 10.2 mmol) and benzyl N-(2,2,2-
trichloroethoxycarbonyI)-L-serine (4.16g, 11.2 mmol) in anhydrous CH2C12 (15
mL) was
treated dropwise with boron trifluoride etherate (2.59 mlõ 20.4 mmol) and then
stirred at
room temperature for 2 h. The reaction mixture was quenched with saturated aq.
NaHCO3
(20 mL) and the layers separated. The aqueous layer was extracted with CHC13
(2x10 mL)
and the combined organic layers were washed with H20 (10 mL), dried (Na2SO4),
and
concentrated in vacuo. Flash chromatography on silica gel (gradient elution,
20-)50%
AcOEt/hexanes) afforded 7.42 g (87%) of N-(2,2,2-trichloroethoxycarbony1)-
043,4,6-tetra-
=
0-acety1-2-deoxy-2-(2,2,2-trichloroethoxycarbonylamino)13-D-gincopyranosyl]-L-
serine
benzyl ester as a white solid (compound 9; Xkl, n=m=p=q*:), r=10, R4=R5=R7=}1,
R6=02Bn).
[0074] (2) A solution of the compound prepared in (1) above (408 mg, 0.49
mmol) in
tetahydrofuran (Till?; 20 mL) was hydrogenated in the presence of 10%
palladium on carbon
(30 mg) at room temperature and atmospheric pressure for 3 h. The reaction
mixture was
TM
filtered through Celite and the filtrate was concentrated in vacuo. Flash
chromatography on
silica gel with 2% Me0H-CHC13 followed by 10% Me0H-CHCI3 afforded 347 mg (98%)
of
N-(2,2,2-trichloroethoxycarbony1)-043,4,6-tetra-0-acetyl-2-deoxy-2-(2,2,2-
27
CA 02738235 2011-04-18
trich1oroeth.oxycarbony1aminol-13-D-g1ucopyranosy11-L-serine as a white solid.
(compound
9; Xt:), n.--gn=p=q=0, R4=125=R7,---H, R6-02H)
[00751 (3) A solution of the compound prepared in (2) above (998 mg, 1.34
mmol) in
methanol (15.5 mL) was treated with ammonium hydroxide (021 m1õ 5.37 mmol) at
room
temperature for 16 h, followed by additional ammonium hydroxide (0.21 mL, 5.37
mmol) for
24 h. The reaction mixture was concentrated in vacuo and to eve a white solid.
A suspension
of the white solid in CH2Cl2 (33.5 mL) was treated with benzyl bromide (0.80
ml,, 6.7
mmol), tetrabutylammonium bromide (432 mg, 1.34 mmol) and saturated NaHCO3
(33.5
raL) and the resulting biphasic mixture was stirred vigorously at room
temperature for 24 h
and the layers separated. The aqueous layer was extracted with CHC13 (2x15mL)
and the
combined organic layers were washed with 1120 (10 mL), dried (Na2SO4), and
concentrated
in vacuo. The resulting residue was dissolved in anhydrous pyridine (10 mL),
treated with t-
butyldimethylsilyl chloride (242 mg, 1.61 mmol), and stirred at room
temperature for 1.5 h.
The reaction mixture was treated with additional t-buryldimethylsily1 chloride
(242 mg, 1.61
mmol) and stirred 1.5 h. The reaction mixture was partitioned between CHCI3(10
mL) and
H20 (10 mL). The aqueous layer was extracted with CHC13 (2x15 mL) and the
combined
organic layers were washed with H20 (15 mL), dried (Na2SO4) and concentrated
in vacuo.
Flash chromatography on silica gel using gradient elution (1.0 3 1.25%
CH3OH/CHC13)
afforded 724 mg (66%) of N-(2,2,2-trichloroethoxycarbony1)-046-0-t-
butyldimethylsily1-2-
deoxy-2-(2,2,2-trichloroethoxycarbonylamino)-13-D-glueopyranosyli-L-serine
benzyl ester as
a white solid. (compound 12 PG=Troc, R6-02H)
[0076] (4) A solution of the compound prepared in (3) above (892 mg, 1.09
mmol) in
anhydrous CH2C12 (10.5 raL) was treated with (R)-3-decanoyloxytetra.decanoic
acid (476 mg,
1.20 mmol), 1-(3-dimethylaminopropy1)-3-ethylcarbodiimide methiodide (EDC-MeI;
355
mg, 1.20 mmol), and 4-pyrrolidinopyridine (8 mg, 0.054 mmol) at 0 C for 1 h.
The reaction
mixture was treated with additional (R)-3-decanoyloxytetradecanoic acid (60
mg) and
EDC.MeI (60 mg) at 0 C, stirred 30 min, and concentrated in vacua. Flash
chromatography
on silica gel with 1:6 AcOEt-hexanes afforded 1.10 g (85%) of N-(2,2,2-
trichloroethoxy-
carbony1)-046-0-t-butyldimetbylsily1-3-0-[(R)-3-decanoyloxytetradecanoy11-2-
deoxy-2-
(2,2,2-trichloroethoxycarbonylamino)-13-D-glucopyranosyli-L-serine benzyl
ester as a
colorless oil.
28
CA 02738235 2011-04-18
[0077] (5) A solution of the compound prepared in (4) above (1.162 g, 0.967
mmol) in
20% aq. THF (16 mL) was treated with zinc dust (632 mg, 9.67 mmol) and acetic
acid (0.12
mlõ 2.13 mnil,p1) and stirred for 1 h at room temperature. The reaction
mixture was filtered
through Celite and the filtrate concentrated in vacuo. The resulting off-white
solid was
dissolved in CHC13 (15 rn.L) and washed successively vvith 15 mL portions of
0.1M HO,
saturated aq Nal1CO3, and 1120. The organic layer was dried (Na2SO4) and
concentrated in
vacuo and the resulting residue was dried overnight under high vacuum. A
solution of the
residue in anhydrous CH2C12 (9.5 mL) was treated with (R)-3-
dec,anoyloxytetradecanoic acid
(848 mg, 2.13 mmol) and EDC.Mei (632 mg, 2.13 mmol) and stirred at room
temperature for
2 h. The reaction mixture was concentrated in vacuo and the residue obtained
purified by
flash chromatography on silica gel (gradient elution; 20325% AcOEt/hexanes) to
give 1.03
g (66%) of N-[(R)-3-decanoyloxytetradecanoy1]-046-0-t-butyldimethylsily1-2-
deoxy-2-[(R)-
3-decanoyloxytetradecanoylaraino]-3-0-[(R)-3-decanoyloxytetradecanoy11-11-D-
glucopyranosyll-L-serine benzyl ester as a glassy solid. (compound 13
Iti=R2=R3=n-
C9HisCO3 X=0, n=1w=p=q=0, r=10, ReR5=R7=11, R5---0O2Bn).
100781 (6) A solution of the compound prepared in (5) above (112 mg, 0.069
mmol) in
anhydrous dichloromethane (1 mL) under argon was treated with dibenzyl
diisopropyl
phosphoramidite (3911,L, 0.12 mmol) and tetrazole (12 mg, 0.173 mmol) and
stirred at room
temperature for 1 h. The reaction mixture was cooled to 0 C and treated with m-
chloroperbenzoic acid (m-CPBA; 33 mg, 0193 mmol) for 30 min. The reaction
mixture was
quenched by addition of saturated aq NaHCO3 (5 mL) and stirred at room
temperature for 15
min. The aqueous layer was extracted with chloroform (3x5 mL) and the combined
organic
layers were washed with water (5 mL), dried (Na2SO4), and concentrated in
vacuo. Flash
chromatography with 25% AcOEt-hexanes gave partially purified product which
was
rechromatographed on silica gel with 20% AcOEt-hexane,s to give 122 mg (93%)
of N-[(R)-
3-decanoyloxytetradecanoy1]-046-0-t-butyldimethylsily1-2-deoxy-4-0-
diphenylphosphono-
2-[(R)-3-decanoyloxytetra.decanoylamino)-3-0-[(R)-3-decanoyloxytetradecanoy1].-
(3-D-
glucopyranosyli-L-serine benzyl ester as a colorless oil.
[0079] (7) A solution of the compound prepared in (6) above (232 mg, 0.124
mmol) in
anhydrous THE? (10 mL) was hydrogenated in the presence of 20% palladium
hydroxide on
carbon (46 mg) at room temperature and atmospheric pressure for 36 h. The
reaction mixture
was filtered through Celite and the filtrate concentrated under vacuum. The
resulting oil (181
mg) was dissolved in CH2C12 (2.5 mL) and treated with nifluoroacetic acid (29
ilL) and
29
CA 02738235 2011-04-18
stirred under argon at room temperature for 18 h. The reaction mixture was
concentrated and
co-evaporated with hexanes (2x5 mL). Flash chromatography on silica gel with
chloroform-
methanol-water-triethylamine (gradient elution; 87:12:0.5:0.5477:22.5:0.5:0.5)
afforded 102
mg (55%) of NA(R)-3-decanoyloxytetGradecanoyl]-042-deoxy-4-0-phosphono-2-[(R)-
3-
decanoyloxytetradecanoylamino]-3-0-[(R)-3-decanoyloxytetradecanoyll-p-D-
glucopyranosyl]-L-serine triethylammonium salt (RC-527) as a colorless solid.
Example 3.- Preparation of (S)-2-11R1-3-Hexanoylovetetradecanovlaminol-3-
phosphonooxypropvl 2-Deoxv-4-0-phosphono-3-0-f(R)-3-bexanovloxytetradecanov11-
2-r(R)-3-bexanovloxytetradecanovlaminoJ-13-D-Elueopyranoside
Bis(triethvflammonium
Salt [a compound of Formula (1) in which X is (1a), namely RI=R2=R3=n-05HIIC0,
Z=Y=0, n=m=p=q=0, r=10, R4=R5=R7=R9=H, R6sH2OPO3H2, R8=P03H21, namely:
OH
CH2OPO3Hz
H203P0
0
NH
010
0 0
0
0 0
01
=
[0080] This example utilizes a process as shown in Scheme 1.
[0081] (1) In the same manner as described in Example 2-(3), 1,3,4,6-tetra-0-
acety1-2-
deoxy-2-(2,2,2-trichloroethoxycarbonylamino)-p-D-glucopyranoside (0.62 g, 1.18
mmol) and
(S)-2-(2,2,2-trichloroethoxycarbonylamino)-3-benzy1oxy-1-Propanol (0.46 g,
1.30 mmol)
were coupled in the presence of boron trifluoride etherate (0.3 mL, 2.4 mmol)
to give (R)-2-
(2,2,2-trichloroethoxycarbonylaraino)-3-benzy1oxy-1-propyl 2-deoxy-3,4,6-tetra-
0-acety1-2-
CA 02738235 2011-04-18
(212,2-trich1oroethoxycarbonylamino)-3-D-g1ucopyranoside as a light yellow
solid.
= (compound 9; X=0, n=m=p=q=0, r=10, R4=R5=R7=H, R6=CH20Bn). A solution of
this
compound in methanol (15 mL) was treated with ammonium hydroxide (0.21 ml,,
5.37
ramol) at room temperature for 19 h, followed by additional ammonium hydroxide
(0.20 mlõ
5.1 mmol) for 25 h. The reaction mixture was concentrated in vacuo and to give
a white solid.
Flash chromatography on silica gel (gradient elution 536% CH3OH/CHC13)
afforded 0.57 g
(63%) of 3-benzyloxy-(R)-2-(2,2,2-trichloroethoxycarbonylamino)propyl 2-deoxy-
2-(2,2,2-
trichloroethoxycarbonylamino)-P-D-glucopyranoside as a glassy solid.
[0082] (2) A solution of the compound prepared in (2) above (0.57 g, 0.83
mmol) in
anhydrous pyridine (8.5 mL) was treated with t-butyldimethylsilyl chloride
(0.15 g, 0.99
mmol) and stirred at room temperature for 1.5 h. Additional t-
butyldimethylsily1 chloride
(0.15 g, 0.99 mmol) was added and after another 1.5 h the reaction mixture was
partitioned
between CHCI3 (10 mL) and H20 (10 mL) and the layers separated. The aqueous
layer was
extracted CHCb (2x10 mL) and the combined organic layers were washed with 1120
(10
mL), dried (Na2SO4), and concentrated in vacuo. Flash chromatography on silica
gel
(gradient elution; 80:1360:1 CHC13/CH3OH) afforded 0.65 g (98%) of 3-benzyloxy-
(R)-2-
(2,2,2-trichloroethoxycarbonylamino)propyl 6-0-t-butyldimethylsily1-2-deoxy-2-
(2,2,2-
trichloroethoxycarboiaylamino)-13-D-glucopyranoside as a white solid.
[0083] (3) hi the same manner as described in Example 2-(4), the compound
prepared in
(2) above (0.47 g, 0.59 mmol) was acylated with (R)-3-hexanoyloxytetradecanoic
acid (0.22
g, 0.64 mmol) in the presence of EDC-Mel (0.21 g, 0.70 mmol) and 4-
pyrrolidinopyridine (4
mg, 0.03 mmol) to afford 0.58 8(88 %) of 3-benzyloxy-(R)-2-(2,2,2-
trichloroethoxy-
carbonylamino)propyl 6-0-t-butyldimethylsily1-3-0-[(R)-3-
hexanoyloxytetradecanoy1]-2-
deoxy-2-(2,2,2-trichloroethoxycarbonylamino)-13-D-glucopyranoside as a
colorless oil.
[0084] (4) In the same manner as described in Example 2-(5), the compound
prepared in
(3) above (0.58 g, 0.51 mmol) was deprotected with zinc (0.34 g, 5.14 mmol)
and acylated
with (R)-3-hexanoyloxytetradecanoic acid (0.39 g, 1.13 mmol) in the presence
of EDC.MeI
(0.34 g, 1.13 roma) to afford 0.41 g (56%) of 3-benzyloxy-(R)-2-{(R)-3-
hexanoyloxy-
tetradecanoylamino}propyl 6-0-t-butyldimethylsily1-3-0-[(R)-3-
hexanoyloxytetradecanoy1]-
2-deoxy-2-[(R)-3-hexanoyloxytetradecanoylaminol-P-D-glucopyranoside as a
colorless oil
(compound 13 It1=rt2=R3=n-05H11CO, X=0, ni--ra=p=q=0, r=10, R4=R5=R7=H,
R6H20Bn).
31
CA 02738235 2011-04-18
[00851 (5) A solution of the compound prepared in (4) above (0.41 g, 0.29
minol) in THF
(18 mL) was hydrogenated in the presence of palladium hydroxide (0.04 g) at
room
temperature and atmospheric pressure for 17 h. The reaction mixture was
filtered through
TM
Celite, and the filtrate concentrated in vacuo. Flash Chromatography on silica
gel (gradient
elution; 1:241:8 ethyl acetate/heptan.e) provided 0.3 g (77%) of 3-hydroxy-(R)-
2-[(R)-3-
hexanoyloxytetradecanoylaminoipropyl 6-0-t-butyldimethyLsily1-3-0-[(R)-3-
hexanoyloxytetradecanoy13-2-deoxy-2-[(R)-3-hexan.oyloxytetradecanoylaminol-13-
D-
glucopyranoside as a colorless oil (compound 13 RI=R2=R3=n-C3H11CO3 X=0,
n=m97--q=0, r=10, R.4=R3=R7=H, ReCI-120H).
[0086] (6) In the same manner as described in Example 2-(6), the compound
prepared in
(5) above (0.30 g, 0.22 pamol) was phosphorylated with dibenzyl
diisopropylphosphoramidite
(0.25 mL, 0.75 mmol), tetrazole (0.08 g, 1.11 mmol), and m-CPBA (0.33 g, 1.95
mmol) to
give 0.30 g (73%) of 3-dibenzylphosphonooxy-(R)-2-[(R)-3-hexanoyloxy-
tetradecanoylamino]propyl 4-dibenzylphosphono-6-0-t-butyldimethylsily1-3-0-
[(R)-3-
hexanoyloxytetradecanoy1]-2-deoxy-2-1(R)-3-hexanoyloxytetradecanoylaminol-13-D-
glucopyranoside as a colorless oil.
[00871 (7) A solution of the compound prepared in (6) above (302 mg, 0.16
mmol) in
anhydrous TBF (13 mL) was hydrogenated in the presence of 20% palladium
hydroxide on
carbon (60 mg) at room temperature and atmospheric pressure for 27 h. The
reaction mixture
TM
was filtered through Celite and the filtrate concentrated in vacuo. A solution
of the resulting
oil (226 mg) in CH2C12 (3.5 inL) was treated with trifluoroacetic acid (0.04
m1,, 0.49 imnol)
and stirred under argon at room temperature for 16 h. The reaction mixture was
concentrated
and co-evaporated with hexanes (2x5 mL), and the resulting residue dried under
high vacuum
to give crude product (226 mg). A portion of the crude product (102 mg) was
dissolved in
1:2 CHC13/CH3OH (9 mL), loaded onto a DEAE-cellulose column (15 g, fast flow,
Sigma),
and. eluted with 2:3:1 CHC13:CH3OH:H20 using a 0 to 0.1 MNH40Ac salt gradient.
The
fractions containing purified product were combined, washed with 0.1 N aq HCI,
and
concentrated in vacuo. The residue obtained was lyophilized from 1% aq
triethylamine
(pyrogen free) to give 82 mg (81%) (S)-2-[(R)-3-hexanoyloxytetradecanoy1amino]-
3-
phosphonooxypropyl 2-deoxy-4-0-ph.osphono-3O-[(R)-3-hexanoyloxytetradecanoyfl-
2-
. [(R)-3-hercanoyloxytetradecattoylaminol-p-D-glucopyranoside
bis(triethyl)amraonium salt as
a white powder: positive FAB-MS calcd for [M+Nar 1407.8534, found 1407.8689;
1}1
NMR (CDC13/ CD30D): 8 (ppm) 5.23-5.16 (m, 4H), 4.67 (d, 111), 4.38 (dd, 1H),
4.19-3.83
=
32
CA 02738235 2012-10-19
(3n, 7H), 3.49 (m, 2H), 3.06 (m, 1211), 2.64-2.23. (m, 1210, 1.584.56 (m,
1210, 1.23 (in, 94
HI 0.88-0.87 (m, 18H). 13C MR (CDC13/ CD30D): (ppm) 173.7, 173.3, 173.2,
170.3,
170.1, 100.0, 74.6, 74.0, 70.9, 70.8, 70.3, 66.6, 63.5, 60.4, 54.2, 45.8,
41.1, 40.7, 39.3, 34.4,
34.3, 31.9, 313, 2.9.7, 29.4, 25.3, 24.7, 22.7, 22.3, 14.1, 13.9, 8.5.
=
=
33
