U.S. patent number RE35,593 [Application Number 08/585,113] was granted by the patent office on 1997-08-19 for azabicylo oxime compounds.
This patent grant is currently assigned to Beecham Group p.l.c.. Invention is credited to Steven M. Bromidge, Steven Dabbs, Barry S. Orlek.
United States Patent |
RE35,593 |
Orlek , et al. |
August 19, 1997 |
Azabicylo oxime compounds
Abstract
A compound of formula (I) or a pharmaceutically acceptable salt
thereof: ##STR1## wherein R.sup.1 represents ##STR2## in which each
of p and q independently represents an integer of 2 to 4, r
represents an integer of 2 to 4, s represents 1 or 2 and t
represents 0 or 1; R.sub.2 is a group OR.sub.4, where R.sub.4 is
C.sub.1-4 alkyl, C.sub.2-4 alkenyl, C.sub.2-4 alkynyl, a group
OCOR.sub.5 where R.sub.5 is hydrogen or R.sub.4, or a group
NHR.sub.6 or NR.sub.7 R.sub.8 where R.sub.6, R.sub.7 and R.sub.8
are independently C.sub.1-2 alkyl; and R.sub.3 is chloro, fluoro,
bromo, cyclopropyl, C.sub.1-3 alkyl substituted by one, two or
three halogen atoms, or R.sub.3 is a group (CH.sub.2).sub.n R.sub.9
where R.sub.9 is --CN, --OH, --OCH.sub.3, --SH, --SCH.sub.3,
--C.tbd.CH or --CH.dbd.CH.sub.2 and n is O or 1, with the proviso
that when n is 0, R.sub.9 is not --OH or --SH.
Inventors: |
Orlek; Barry S. (Harlow,
GB2), Bromidge; Steven M. (Harlow, GB2),
Dabbs; Steven (Harlow, GB2) |
Assignee: |
Beecham Group p.l.c.
(Brentwood) N/A)
|
Family
ID: |
26295213 |
Appl.
No.: |
08/585,113 |
Filed: |
January 11, 1996 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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508100 |
Apr 11, 1990 |
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Reissue of: |
785884 |
Oct 30, 1991 |
05278170 |
Jan 11, 1994 |
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Foreign Application Priority Data
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Apr 13, 1989 [GB] |
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8908365 |
Oct 16, 1989 [GB] |
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8923299 |
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Current U.S.
Class: |
514/304; 514/305;
514/413; 546/124; 546/133; 548/453 |
Current CPC
Class: |
A61P
25/00 (20180101); C07D 487/08 (20130101); C07D
453/02 (20130101); A61P 25/28 (20180101); A61P
25/02 (20180101); C07D 471/08 (20130101) |
Current International
Class: |
C07D
453/02 (20060101); C07D 453/00 (20060101); C07D
471/00 (20060101); C07D 471/08 (20060101); C07D
487/08 (20060101); C07D 487/00 (20060101); C07D
471/08 (); C07D 453/02 (); A61K 031/435 (); A61K
031/42 () |
Field of
Search: |
;514/304,305,413
;546/124,133 ;548/453 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0094742 |
|
Nov 1983 |
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EP |
|
239445 |
|
Sep 1987 |
|
EP |
|
0261763 |
|
Mar 1988 |
|
EP |
|
0257741 |
|
Mar 1988 |
|
EP |
|
271798 |
|
Jun 1988 |
|
EP |
|
0287356 |
|
Oct 1988 |
|
EP |
|
288394 |
|
Oct 1988 |
|
EP |
|
0291673 |
|
Nov 1988 |
|
EP |
|
308283 |
|
Mar 1989 |
|
EP |
|
308284 |
|
Mar 1989 |
|
EP |
|
0338723 |
|
Oct 1989 |
|
EP |
|
0316713 |
|
Dec 1989 |
|
EP |
|
Primary Examiner: Powers; Fiona
Attorney, Agent or Firm: Hopgood, Calimafde, Kalil &
Judlowe
Parent Case Text
This application is a continuation of application Ser. No. 508,100,
filed Apr. 11, 1990, now abandoned.
Claims
We claim:
1. A compound of formula (I) or a pharmaceutically acceptable salt
thereof: ##STR72## wherein R.sub.1 represents ##STR73## in which
each of p and q independently represents an integer of 2 to 4, r
represents an integer of 2 to 4, s represents 1 or 2 and t
represents 0 or 1;
R.sub.2 is a group OR.sub.4 where R.sub.4 is C.sub.1-4 alkyl,
C.sub.2-4 alkenyl, C.sub.2-4 alkynyl, a group OCOR.sub.5 where
R.sub.5 is hydrogen or R.sub.4, or a group NHR.sub.6 or NR.sub.7
R.sub.8 where R.sub.6, R.sub.7 and R.sub.8 are independently
C.sub.1-2 alkyl; and
R.sub.3 is chloro, fluoro, bromo, C.sub.1-3 alkyl substituted by
one, two or three halogen atoms, --CN, .[.--CN.sub.2 CN.].,
.Iadd.CH.sub.2 CN.Iaddend., --SCH.sub.3, or --O--CH.sub.3.
2. A compound according to claim 1, in which p represents 2 and q
represents 2 or 3, or the combination (r,s,t) takes the value
(2,2,0), (2,1,1), (3,1,1), (2,1,0) or (3,1,0).
3. A compound according to claim 1, in which R.sub.2 is methoxy,
ethoxy, allyloxy, propargyloxy, acetoxy or dimethylamino.
4. A compound according to claim 1, in which R.sub.3 is chloro,
fluoro, bromo, CN, OCH.sub.3, or --CH.sub.2 CN.
5. (.+-.) 1-Azabicyclo[2.2.2]oct-3-yl-N-methoxycarboximidoyl
chloride,
(.+-.) 1-azabicyclo[2.2.2]oct-3-yl-N-methoxycarboximidic acid
methyl ester,
(.+-.)
.alpha.-(methoxyimino)-.alpha.-(1-azabicyclo[2.2.2]oct-3-yl)acetonitrile,
(.+-.) 1-azabicyclo[3.2.1]oct-5-yl-N-methoxycarboximidoyl
chloride,
(.+-.)
.alpha.-(methoxyimino)-.alpha.-(1-azabicyclo[3.2.1]oct-5-yl)acetonitrile,
(.+-.) 1-azabicyclo[3.2.1]oct-5-yl-N-methoxycarboximidoyl
bromide,
(.+-.) exo-1-azabicyclo[2,2,1]hept-3-yl-N-methoxycarboximidoyl
chloride,
(.+-.)
exo-.alpha.-(methoxyimino)-.alpha.-(1-azabicyclo[2,2,1]hept-3-yl)acetonitr
ile,
(.+-.) 1-azabicyclo[2.2.2]oct-3-yl-N-methoxycarboximidoyl
fluoride,
1-azabicyclo[2,2,1]hept-5-yl-N-methoxycarboximidoyl chloride,
.alpha.-(methoxyimino)-.alpha.-(1-azabicyclo[2,2,1]hept-4-yl)
acetonitrile,
1-azabicyclo[2,2,1]hept-4-yl-N-methoxycarboximidoyl bromide,
1-azabicyclo[2,2,1]hept-4-yl-N-methoxycarboximidoyl fluoride,
(.+-.) endo-1-azabicyclo[2,2,1]hept-3-yl-N-methoxycarboximidoyl
chloride,
(.+-.)
endo-.alpha.-(methoxyimino)-.alpha.-(1-azabicyclo[2,2,1]hept-3-yl)acetonit
rile,
(.+-.) exo-1-azabicyclo[2,2,1]hept-3-yl-N-methoxycarboximidoyl
bromide,
(.+-.) endo-1-azabicyclo[2,2,1]hept-3-yl-N-methoxycarboximidoyl
bromide,
(.+-.) exo-1-azabicyclo[2,2,1]hept-3-yl-N-methoxycarboximidoyl
fluoride,
(.+-.) exo-1-azabicyclo[2,2,1]hept-3-yl-N-ethoxycarboximidoyl
chloride,
(.+-.)
exo-.alpha.-(ethoxyimino)-.alpha.-(1-azabicyclo[2,2,1]hept-3-yl)acetonitri
le,
(.+-.) exo-1-azabicyclo[2,2,1]hept-3-yl-N-ethoxycarboximidoyl
bromide, (.+-.)
exo-1-azabicyclo[2,2,1]hept-3-yl-N-prop-2-ynyloxy-carboximidoyl
chloride,
(.+-.)
endo-1-azabicyclo[2,2,1]hept-3-yl-N-prop-2-ynyloxy-carboximidoyl
chloride,
(.+-.)
exo-3-oxo-3-(1-azabicyclo[2,2,1]hept-3-yl)propionitrile-O-methyl
oxime,
(.+-.)
endo-3-oxo-3-(1-azabicyclo[2,2,1]hept-3-yl)propionitrile-O-methyl
oxime,
(-) .alpha.-(methoxyimino)-.alpha.-(1-azabicyclo[2.2.2]oct-3-yl)
acetonitrile,
(+) .alpha.-(methoxyimino)-.alpha.-(1-azabicyclo[2.2.2]oct-3-yl)
acetonitrile or
(.+-.) 1-azabicyclo[3.2.1]oct-5-yl-N-methoxycarboximidoyl fluoride,
or a pharmaceutically acceptable salt of any of the foregoing
compounds.
6. A compound of formula (IIa): ##STR74## wherein R.sub.2 '
represents hydroxy and R.sub.1 and R.sub.3 are as defined in claim
1 .Iadd.with the proviso that R.sub.3 is not Br.Iaddend..
7. A pharmaceutical composition which comprises an effective amount
of a compound according to claim 1 and a pharmaceutically
acceptable carrier.
8. A method of treatment or prophylaxis of dementia in mammals,
which comprises administering to the sufferer an effective amount
of a compound according to claim 1. .Iadd.9. (-)
.alpha.-(Methoxyimino)-.alpha.-(1-azabicyclo[2.2.2]oct-3-yl)acetonitrile
or a pharmaceutically acceptable salt thereof. .Iaddend..Iadd.10.
(+)
.alpha.-(Methoxyimino)-.alpha.-(1-azabicyclo[2.2.2]oct-3-yl)acetonitrile
or a pharmaceutically acceptable salt thereof. .Iaddend..Iadd.11. A
pharmaceutical composition comprising an effective amount of a
compound defined by claim 9 and a pharmaceutically acceptable
carrier therefor. .Iaddend..Iadd.12. A pharmaceutical composition
comprising an effective amount of a compound defined by claim 10
and a pharmaceutically acceptable carrier therefor.
.Iaddend..Iadd.13. A method of treatment or prophylaxis of dementia
in mammals comprising administering to said mammal an effective
amount of a compound defined by claim 9. .Iaddend..Iadd.14. A
method of treatment or prophylaxis of dementia in mammals
comprising administering to said mammal an effective amount of a
compound defined by claim 10. .Iaddend.
Description
This invention relates to compounds having pharmaceutical activity,
to a process for their preparation and their use as
pharmaceuticals.
EP-A-0257741 and EP-A No. 0338723 (Beecham Group p.l.c.) disclose
certain azabicyclic compounds which enhance acetylcholine function
via an action at muscarinic receptors within the central nervous
system. EP-A-0316718 (Ferrosan) discloses certain azabicyclic
muscarinic cholinergic compounds.
A novel group of compounds has now been discovered which also
enhance acetylcholine function via an action at muscarinic
receptors within the central nervous system and are therefore of
potential use in the treatment and/or prophylaxis of dementia in
mammals.
According to the present invention, there is provided a compound of
formula (I) or a pharmaceutically acceptable salt thereof: ##STR3##
wherein R.sub.1 represents ##STR4## in which each of p and q
independently represents an integer of 2 to 4, r represents an
integer of 2 to 4, s represents 1 or 2 and t represents 0 or 1;
R.sub.2 is a group OR.sub.4, where R.sub.4 is C.sub.1-4 alkyl,
C.sub.2-4 alkenyl, C.sub.2-4 alkynyl, a group OCOR.sub.5 where
R.sub.5 is hydrogen or R.sub.4, or a group NHR.sub.6 or NR.sub.7
R.sub.8 where R.sub.6, R.sub.7 and R.sub.8 are independently
C.sub.1-2 alkyl; and
R.sub.3 is chloro, fluoro, bromo, cyclopropyl, C.sub.1-3 alkyl
substituted by one, two or three halogen atoms, or R.sub.3 is a
group (CH.sub.2).sub.n R.sub.9 where R.sub.9 is --CN, --OH,
--OCH.sub.3, --SH, --SCH.sub.3, --C.tbd.CH or --CH.dbd.CH.sub.2 and
n is O or 1, with the proviso that when n is O, R.sub.9 is not --OH
or --SH.
The term halogen includes bromine, chlorine, fluorine and iodine,
preferably fluorine.
Compounds of formula (I) are capable of existing in a number of
stereoisomeric forms including geometric isomers such as syn and
anti and, for certain compounds, enantiomers. The invention extends
to each of these stereoisomeric forms, and to mixtures thereof
(including racemates). The different stereoisomeric forms may be
separated one from the other by the usual methods, or any given
isomer may be obtained by stereospecific or asymmetric
synthesis.
Compounds of formula (I) having two assymetric centres which have
the stereochemical configuration in which the group
--C(R.sub.3).dbd.NR.sub.2 and the (CH.sub.2).sub.s bridge are on
the same side of the plane of the molecule which contains both
bridgehead atoms and the ring carbon atom bonded to the aforesaid
group will hereinafter be referred to as having the exo
configuration.
The compounds of formula (I) can form acid addition salts with
acids, such as the conventional pharmaceutically acceptable acids,
for example hydrochloric, hydrobromic, phosphoric, acetic, fumaric,
salicylic, citric, lactic, mandelic, tartaric, oxalic and
methanesulphonic.
The term pharmaceutically acceptable salt encompasses solvates and
hydrates. Thus where compounds of formula (I) or pharmaceutically
acceptable salts thereof form solvates or hydrates, these also form
an aspect of the invention.
Preferably, p and q each independently represents 2 or 3. Most
preferably p represents 2 and q represents 2 or 3.
Preferred combinations of (r,s,t) include (2,2,0), (2,1,1),
(3,1,1), (2,1,0) and (3,1,0), most preferably (2,2,0).
The groups R.sub.4 and R.sub.5 in R.sub.2 are preferably selected
from methyl, ethyl, allyl and propargyl. R.sub.6, R.sub.7 and
R.sub.8 are preferably methyl. Suitable values for R.sub.2 include
methoxy, ethoxy, allyloxy, propargyloxy, acetoxy and dimethylamino,
preferably methoxy.
Suitable examples for R.sub.3 include cyclopropyl, chloro, fluoro
and bromo and when R.sub.3 is a group (CH.sub.2).sub.n R.sub.9 and
n is O, suitable examples of R.sub.9 include --CN, --OCH.sub.3 or
--C.tbd.CH, preferably CN. When n is 1, an example of R.sub.9 is
CN.
The invention also provides a process for the preparation of a
compound of formula (I), or a pharmaceutically acceptable salt
thereof, which process comprises:
(a) reacting a compound of formula (II): ##STR5## with a compound
of formula (III):
wherein R.sub.2 ' represents R.sub.2 or hydroxy, and R.sub.3 '
represents R.sub.3 or a group convertible thereto, converting
R.sub.2 ' to R.sub.2 when hydroxy, converting R.sub.3 ' when other
than R.sub.3 to R.sub.3, wherein R.sub.1, R.sub.2 and R.sub.3 are
as defined in formula (I), and thereafter optionally forming a
pharmaceutically acceptable salt;
(b) reacting a compound of formula (IV): ##STR6## with a compound
of formula (V):
capable of generating an R.sub.3 ' nucleophile wherein R.sub.3 '
represents R.sub.3 or a group convertible thereto, converting
R.sub.3 ' when other than R.sub.3 to R.sub.3, wherein R.sub.1,
R.sub.2 and R.sub.3 are as defined in formula (I), and thereafter
optionally forming a pharmaceutically acceptable salt; or
(c) reacting a compound of formula (IVa) ##STR7## wherein R.sub.1
and R.sub.2 are as defined in formula (I), with a chlorinating,
brominating or fluorinating agent, optionally converting R.sub.3
when chloro or bromo to other R.sub.3, and thereafter optionally
forming a pharmaceutically acceptable salt.
It will be appreciated that compounds of formula (IV) are identical
to compounds of formula (I) in which R.sub.3 is chloro or bromo,
and as such are themselves part of the invention.
The reaction between the compounds of formulae (II) and (III) is
preferably carried out in a hydroxylic solvent such as methanol or
ethanol, at ambient temperature, or where appropriate, at elevated
temperature.
Where R.sub.2 in compounds of formula (I) is a group OR.sub.4,
NHR.sub.6 or NR.sub.7 R.sub.8, a compound of formula (II) is
conveniently reacted with a compound of formula (III) in which
R.sub.2 ' is R.sub.2.
Where R.sub.2 in compounds of formula (I) is a group OCOR.sub.5, a
compound of formula (II) may be reacted with the compound of
formula (III) in which R.sub.2 ' is hydroxy, with subsequent
acylation of the resulting oxime by treatment with a suitable
acylating agent such as an acyl halide, for example acetyl
chloride.
The reaction between compounds of formulae (IV) and (V) may be
carried out under standard conditions for the displacement of
halogen by a nucleophile.
Where R.sub.3 in compounds of formula (I) is fluoro, the residue M
is suitably caesium, the caesium fluoride reagent being supported
on calcium fluoride in dimethylformamide at elevated temperature
for a prolonged period. This route for introduction of R.sub.3
fluoro is preferred where R.sub.1 represents group (B).
Where R.sub.3 in compounds of formula (I) is a group
(CH.sub.2).sub.n R.sub.9 and n is O, the residue M is suitably an
alkali metal such as sodium or lithium. Where, for example, R.sub.9
is --CN or --OCH.sub.3, the reaction is conveniently carried out at
elevated temperature in an inert solvent such as dimethylsulphoxide
or methanol.
Where R.sub.3 in compounds of formula (I) is a group
(CH.sub.2).sub.n R.sub.9 and n is 1, the compound of formula (V) is
suitably an organolithium or Grignard reagent. The reaction may be
carried out using conditions generally used for reactions with
Grignard reagents, for example using anhydrous reagents under an
inert atmosphere and at reduced temperature.
The product of the reaction of compounds of formulae (II) and (III)
and formulae (IV) and (V) is a compound of formula (IIa): ##STR8##
wherein R.sub.2 ' represents R.sub.2 or hydroxy and R.sub.3 '
represents R.sub.3 or a group convertible thereto, and R.sub.1,
R.sub.2 and R.sub.3 are as defined in formula (I).
Intermediates of formula (IIa) wherein R.sub.2 ' is not R.sub.2
when R.sub.3 ' is R.sub.3, also form part of the invention.
It will be appreciated that the reaction of compounds of formula
(IVa) with a chlorinating, brominating or fluorinating agent will
yield compounds of formula (I) wherein R.sub.3 is chloro, bromo or
fluoro. Suitable chlorinating agents include phosphorus
pentachloride which undergoes reaction in nitromethane at reduced
temperature, for example 0.degree. C., and
dichlorotriphenylphosphine (carbon tetrachloride/triphenyl
phosphine) which undergoes reaction in acetonitrile at elevated
temperature, for example at the boiling point of the solvent.
Suitable brominating agents include dibromotriphenylphosphine
(carbon tetrabromide/triphenylphosphine) which undergoes reaction
in acetonitrile at elevated temperature, for example at the boiling
point of the solvent. Suitable fluorinating agents include
diethylaminosulphur trifluoride (DAST) which also undergoes
reaction in acetonitrile at elevated temperature.
Conversion of the resulting R.sub.3 halogen group when chloro or
bromo to other R.sub.3 groups may be effected by reaction variant
(b) above.
Compounds of formula (II) and compounds of formulae (IV) and (IVa)
may be prepared from an intermediate compound of formula (VI):
##STR9## in which L is a leaving group such as chloro, bromo or
C.sub.1-4 alkoxy and R.sub.1 is as defined in formula (I). A
compound of formula (VI) in which L is preferably chloro or bromo
may be reacted with N,O-dimethylhydroxylamine and the resulting
N-methoxy-N-methylcarboxamide derivative reacted with a compound of
formula (V), suitably an organolithium or Grignard reagent, to
provide a compound of formula (II). Where R.sub.3 is ethnyl, it is
preferably protected in the compound of formula (V) which is
suitably lithium (trimethylsilyl) acetylene. The trimethylsilyl
protecting group is preferably removed after reaction of the
compounds of formulae (II) and (III) by treatment with aqueous
sodium hydroxide.
Where R.sub.3 is cyclopropyl, a compound of formula (VI) in which L
is preferably chloro or bromo may be treated with
cyclopropyltrimethylsilane in the presence of aluminium trichloride
in dichloromethane.
Where R.sub.3 is CH.sub.2 CN, a compound of formula (VI) in which L
is preferably C.sub.1-4 alkoxy may be treated with a suitable
organolithium or Grignard reagent, for example the reaction product
of acetonitrile and lithium diisopropylamide. It will be
appreciated that the resulting compound of formula (lI) will be in
the form of the lithium enolate salt.
A compound of formula (VI) may alternatively be reacted with a
compound of formula (III) wherein R.sub.2 ' is OR.sub.4, in
acetonitrile as solvent, in the presence of a base such as pyridine
or triethylamine, and the resulting derivative of formula (IVa)
treated with a chlorinating or brominating agent to provide a
compound of formula (IV) in which R.sub.2 is OR.sub.4.
Novel compounds of formulae (II) and (Iva) also form part of the
invention.
Compounds of formula (VI) where R.sub.1 represents group (A) may
conveniently be prepared by cyclising a compound of formula (VII):
##STR10## in which (i) A represents a group convertible to COCl and
B represents --(CH.sub.2).sub.j L.sub.1 where L.sub.1 is a leaving
group or A and L.sub.1 together represent --COO--; one of j, k and
l is 1 and the other two independently represent an integer of 2 to
4. and R.sub.10 represents hydrogen or an N-protecting group; to
give a compound of formula (VIIa): ##STR11## in which X represents
a group convertible to COCl or COBr, Z.sup.-- is an anion and the
remaining variables are as previously defined;
or (ii) A represents an electron withdrawing group, B represents
hydrogen and R.sub.10 represents --(CH.sub.2).sub.j L.sub.2 where
L.sub.2 is a leaving group; one of k and l is 1 and the other and j
independently represent an integer of 2 to 4; to give a compound of
formula (VIIb): ##STR12## in which W represents an electron
withdrawing group or X and the remaining variables are as
previously defined;
and thereafter, optionally or as necessary, removing any R.sub.10
N-protecting group, converting W to X and converting X to COCl or
COBr.
The deprotection, conversion and interconversion steps may be
carried out in any appropriate order.
Examples of the leaving groups L.sub.1 and L.sub.2 include halo
such as bromo or chloro, tosyloxy and mesyloxy.
Examples of R.sub.10 when an N-protecting group include benzyl and
substituted benzyl.
Examples of A and X when groups convertible to COCl or COBr include
a C.sub.1-4 alkoxycarbonyl, benzyloxycarbonyl and cyano.
The cyclisation reaction is a nucleophilic substitution which may
be carried out under conventional conditions appropriate to the
groups A and B. Thus, when B is (CH.sub.2).sub.j Br and A is
C.sub.1-4 alkoxycarbonyl, the cyclisation is carried out in an
inert solvent such as toluene or ether at elevated temperature.
When B is (CH.sub.2).sub.j OTos or (CH.sub.2).sub.j OMes, it is
preferably obtained by treatment of a (CH.sub.2).sub.j OH group
with a suitable reagent such as tosyl chloride or mesyl chloride,
in a base such as pyridine, whereupon the cyclisation may proceed
at ambient temperature, or at elevated temperature in an inert
solvent such as toluene. When A and L.sub.1 together represent
--COO--, the cyclisation may be carried out in a lower alkanol such
as ethanol in the presence of acid such as hydrogen bromide. In the
resulting compound of formula (VIIa), X will be an alkoxycarbonyl
group corresponding to the lower alkanol used for the
cyclisation.
Where R.sub.10 is an N-protecting group such as benzyl, this may be
removed by conventional hydrogenation, preferably catalytically
over a suitable catalyst such as Pd/C.
Examples of A when an electron withdrawing group include C.sub.1-4
alkoxycarbonyl and cyano.
When A is an electron withdrawing group such as C.sub.1-4
alkoxycarbonyl, B is hydrogen and R.sub.10 is --(CH.sub.2).sub.j
L.sub.2 where L.sub.2 is, for example, chloro, the cyclisation may
be effected by treatment of the compound of formula (VII) with
lithium diisopropylamide.
Compounds of formula (VI) where R.sub.1 represents group (B) may
conveniently be prepared by:
(a) cyclising a compound of formula (VIIIa): ##STR13## where
R.sub.10 is hydrogen or an N-protecting group, and either C is one,
D is another and E is the remainder of --(CH.sub.2).sub.r --,
--(CH.sub.2).sub.s -- and --(CH.sub.2).sub.t --CHX--CH.sub.2 -- or
groups convertible thereto, X is a group convertible to COCl or
COBr and L.sub.3 is a leaving group, or C is one and E is the other
of --(CH.sub.2).sub.r -- and --(CH.sub.2).sub.s -- or groups
convertible thereto and D represents --(CH.sub.2).sub.t
--CHX--CH.sub.2 -- where X and L.sub.3 together represent --COO--,
and thereafter, optionally or as necessary and in any appropriate
order, converting C, D and E to --(CH.sub.2).sub.r --,
--(CH.sub.2).sub.s -- and --(CH.sub.2).sub.t --CHX--CH.sub.2 --,
removing any R.sub.10 protecting group, and converting X to COCl or
COBr; or
(b) cyclising a compound of formula (VIIIb): ##STR14## where F is
one and G is the other of --(CH.sub.2).sub.r -- and
--(CH.sub.2).sub.s -- or groups convertible thereto, and one of
Y.sup.3 and Y.sup.4 is --(CH.sub.2).sub.m --K and the other is
--(CH.sub.2).sub.n W or (CH.sub.2).sub.n L.sub.4 where K and W are
electron withdrawing groups, L.sub.4 is a leaving group, m is 1 or
2 and n is 0 or 1 with the provisos that, when Y.sup.4 is
--(CH.sub.2).sub.n W, n is 1, and Y.sup.4, is not
--(CH.sub.2).sub.n L.sub.4, and thereafter, optionally or as
necessary and in any appropriate order, hydrolysing and
decarboxylating the cyclisation product and converting the carbonyl
group to --CHX where X is a group convertible to COCl or COBr,
converting W to X as defined, converting X to COCl or COBr,
converting F and G to --(CH.sub.2).sub.r -- and --(CH.sub.2).sub.s
-- as appropriate, m and n being such that the desired compound of
formula (VI) is obtained.
Examples of leaving groups L.sub.3 include halo such as chloro and
hydroxy. Examples of L.sub.4 include those given for L.sub.3 or
C.sub.1-4 alkoxy such as ethoxy. Examples of electron withdrawing
groups K and W include C.sub.1-4 alkoxycarbonyl and cyano. In the
group --(CH.sub.2).sub.t --CHX--CH.sub.2 --, examples of X include
hydroxy and cyano.
In the process variant (a), where L.sub.3 is hydroxy and D is
--CHOH--CH.sub.2 --, the cyclisation may be carried out by
pyrolysis, by the method of D. O. Spry and H. S. Aaron, J. Org.
Chem., 1969, 34. 3674, to yield a compound where X is hydroxy.
Where E is --(CH.sub.2).sub.r COCH.sub.2 --, the cyclisation may be
carried out under basic conditions where R.sub.10 is benzyl (F. I.
Carrol, A. M. Ferguson, and J. B. Lewis, J. Org. Chem. 31, 2957,
1966). The resulting ketone may be reacted with tosylmethyl
isocyanide to yield a compound where X is cyano.
Where L.sub.3 and X together represent --COO--, the cyclisation is
a rearrangement reaction which can be carried out under acid
conditions in a polar solvent, such as hydrogen bromide in ethanol,
at ambient temperature, to yield a compound where X is a carboxy
ester group. It is preferred to protect the nitrogen atom with an
R.sub.10 N-protecting group such as benzyl, which may be
subsequently removed by hydrogenation over a suitable catalyst such
as Pd/C. In the compound of formula (VIIIa) where t=O, C is
--CH.sub.2 -- and E is --(CH.sub.2).sub.2 --, the cyclisation
product is the endo isomer.
In the process variant (b), where Y.sup.3 and Y.sup.4 both contain
carboxy ester groups the cyclisation is a Dieckmann reaction which
is catalysed by a base such as potassium t-butoxide at elevated
temperature in a solvent such as toluene.
The resulting .beta.-keto ester is hydrolysed and decarboxylated
under conventional conditions such as heating at reflux in dilute
hydrochloric acid.
The carbonyl group may then be reduced to an X hydroxy group with a
suitable reducing agent such as sodium borohydride in ethanol at
ambient temperature, or sodium in ethanol at elevated temperature,
such as the boiling point of the solvent, under an inert atmosphere
sphere such as nitrogen, depending upon the stereo-chemistry
required.
Alternatively, the carbonyl group may be converted directly to an X
cyano group with a suitable reagent such as tosylmethylisocyanide
in an inert solvent such as dry dimethoxyethane, at depressed
temperature, under basic conditions such as the presence of
potassium t-butoxide.
In process variant (b) where Y.sup.3 and Y.sup.4 both contain cyano
groups the cyclisation is a Thorpe reaction which is catalysed by a
base such as potassium t-butoxide at elevated temperature in a
solvent such as toluene.
The resulting .beta.-keto nitrile is hydrolysed and decarboxylated
under conventional conditions such as heating at reflux in dilute
hydrochloric acid.
Where Y.sup.3 is --(CH.sub.2).sub.n L.sub.4, the cyclisation may be
carried out as described in EP-A No. 0094742 under basic conditions
such as sodium hydride and potassium t-butoxide, in an inert polar
solvent such as dimethyl formamide.
The conversion of K, W and X to COCl or COBr may be carried out
conventionally.
An X hydroxy group may be converted to cyano by first converting it
to a good laving group such as mesyloxy or tosyloxy and then
displacing it with cyanide ion.
An X carboxy group may be obtained by conventional
de-esterification of an X, K or W alkoxycarbonyl group. Where
R.sub.10 is an N-protecting group and X, K or W is a
benzyloxycarbonyl group, the de-esterification and deprotection
steps may conveniently be effected simultaneously by conventional
hydrogenation such as described above. Alternatively, an X carboxy
group may be obtained by conventional acid hydrolysis of an X, K or
W cyano group. A carboxy group may be treated with thionyl chloride
at elevated temperature to give the chlorocarbonyl group, COCl or
with thionyl bromide to give the bromocarbonyl group, COBr.
Compounds of formula (VII) may be prepared conventionally.
Where A is C.sub.1-4 alkoxycarbonyl, B is (CH.sub.2).sub.j L.sub.1
and R.sub.10 is hydrogen or an N-protecting group, the compound of
formula (VII) may be prepared by treating a compound of formula
(IX): ##STR15## where R.sub.11 is C.sub.1-4 alkyl and the remaining
variables are as previously defined, with lithium diisopropylamide,
prepared in situ from diisopropylamine and n-butyllithium followed
by reaction with a compound L.sub.5 (CH.sub.2).sub.j L.sub.1 where
L.sub.5 is a leaving group, in an inert solvent such as ether at
depressed to elevated temperature. Both L.sub.1 and L.sub.5 are
suitably bromo.
Where A and L.sub.1 together represent --COO-- and j is 2, the
compound of formula (VII) may be prepared by reacting the compound
of formula (IX), treated with lithium diisopropylamide as before,
with ethylene oxide in an inert solvent such as ether at depressed
to elevated temperature.
Alternatively, the compound of formula (VII) where A and L.sub.1
together represent --COO, j is 2, k is 2 and 1 is 1 may be prepared
by a 1,3-dipolar cycloaddition reaction which involves reacting a
compound of formula (X): ##STR16## with a compound of formula (XI):
##STR17## in which R.sub.10 is an N-protecting group in the
presence of a catalytic amount of trifluoroacetic acid.
Where A is an electron withdrawing group such as C.sub.1-4
alkoxycarbonyl, B is hydrogen and R.sub.10 is (CH.sub.2).sub.j
L.sub.2, the compound of formula (VII) may be prepared by reacting
the compound of formula (IX) where R.sub.10 is hydrogen with a
compound L.sub.5 (CH.sub.2).sub.j L.sub.2 where L.sub.5 is as
previously defined, in a solvent such as acetone in the presence of
a base such as potassium carbonate. The leaving group L.sub.5 is
preferably bromo and L.sub.2 is preferably chloro.
Compounds of formula (IX) are known compounds or may be prepared by
analogous methods to those for preparing known compounds. The
compound of formula (IX) where k is 2, l is 1 and R.sub.10 is
benzyl may be prepared by the cyclisation of di-C.sub.1-4 alkyl
itaconate in the appropriate alkanol with benzylamine at elevated
temperature, followed by reduction of the resulting oxo group at
the 2-position of the pyrrolidine ring with BH.sub.3 in
tetrahydrofuran, at ambient to elevated temperature.
Intermediates of formulae (VIIIa) and (VIIIb) are known compounds
(e.g. as described in EP-A-0094742) or may be prepared
analogously.
Intermediates of formula (VIIa) where X and L.sub.3 together
represent --COO--, t=O, C is is --(CH.sub.2).sub.2 -- and E is
--CH.sub.2 -- are described in, for example, Kuthan et al., Coll.
Czechoslov. Chem. Comm., 1977, 42, 283 or may be prepared therefrom
by conventional hydrogenation of the pyridine ring over 5% Pt/C,
and benzylation of the nitrogen atom by treatment with benzyl
bromide and potassium carbonate in dry acetone.
The compound of formula (VIIIa) where X and L.sub.3 together
represent --COO--, t=O, C is --CH.sub.2 -- and E is
--(CH.sub.2).sub.2 -- may be prepared by a 1,3-dipolar
cycloaddition reaction of a compound of formula (XI) with
5,6-dihydro-2H-pyran-2-one in the presence of a catalytic amount of
trifluoroacetic acid.
Intermediates of formula (VIIIa) where L.sub.3 is a leaving group
are described in, for example, Spry et al., J. Org. Chem., 1969,
34, 3674 and Hasse et at., Chem. Ber., 1960, 93. 1686.
Intermediates of formula (VIIIb) are described in, for example,
Martell et al., J. Pharm. Sci., 1963, 52(4), 331 Sternbach et al.,
J.A.C.S., 1952, 74, 2215, Thill et al., J. Org. Chem., 1968, 33,
4376 and EP-A No. 0094742.
Compounds of formula (III) are known compounds or may be prepared
by analogous methods to those for preparing known compounds.
Certain compounds of formula (III) are commercially available.
Compounds of formulae (X) and (XI) may be prepared conventionally.
Thus, a compound of formula (X) may be obtained by the reaction of
.gamma.-butyrolactone with ethyl formate in the presence of base
such as sodium hydride followed by reaction of the resulting formyl
derivative (as the enol salt) with formaldehyde. A compound of
formula (XI) may be obtained by the reaction of the primary amine
R.sub.10 NH.sub.2 successively with chloromethyltrimethylsilane and
formaldehyde followed by methanol and anhydrous potassium
carbonate.
Where applicable, an exo isomer may be obtained by epimerisation of
a corresponding endo isomer and vice versa, the epimerisation
reaction being effected by standard procedures at any convenient
stage in the process.
The different stereoisomeric forms of compounds of formula (I) may
be separated one from the other by the usual methods, for example
using chromatographic methods. Enantiomers may be separated using
chiral resolving agents such as (S)-(+)- and
(R)-(-)-1,1'-binaphthyl-2,2'-diyl hydrogen phosphate, or chiral
chromatography, or any given isomer may be obtained by
stereospecific or asymmetric synthesis.
Pharmaceutically acceptable salts of the compounds of formula (I)
may be formed conventionally by reaction with the appropriate acid
such as described above under formula (I).
The compounds of the present invention enhance acetylcholine
function via an action at muscarinic receptors within the central
nervous system and are therefore of potential use in the treatment
and/or prophylaxis of dementia.
The present invention also provides a pharmaceutical composition,
which comprises a compound of formula (I) or pharmaceutically
acceptable salt thereof, and a pharmaceutically acceptable
carrier.
The compositions may be in the form of tablets, capsules, powders,
granules, lozenges, suppositories, reconstitutable powders, or
liquid preparations such as oral or sterile parenteral solutions or
suspensions.
In order to obtain consistency of administration it is preferred
that a composition of the invention is in the form of a unit
dose.
Unit dose presentation forms for oral administration may be tablets
and capsules and may contain conventional excipients such as
binding agents, for example syrup, acacia, gelatin, sorbitol,
tragacanth, or polyvinylpyrrolidone; fillers, for example lactose,
sugar, maize-starch, calcium phosphate, sorbitol or glycine;
tabletting lubricants, for example magnesium stearate;
disintegrants, for example starch, polyvinylpyrrolidone, sodium
starch glycollate or microcrystalline cellulose; or
pharmaceutically acceptable wetting agents such as sodium lauryl
sulphate.
The solid oral compositions may be prepared by conventional methods
of blending, filling, tabletting or the like. Repeated blending
operations may be used to distribute the active agent throughout
those compositions employing large quantities of fillers. Such
operations are of course conventional in the art. The tablets may
be coated according to methods well known in normal pharmaceutical
practice, in particular with an enteric coating.
Oral liquid preparations may be in the form of, for example,
emulsions, syrups, or elixirs, or may be presented as a dry product
for reconstitution with water or other suitable vehicle before use.
Such liquid preparations may contain conventional additives such as
suspending agents, for example sorbitol, syrup, methyl cellulose,
gelatin, hydroxyethylcellulose, carboxymethylcellulose, aluminium
stearate gel, or hydrogenated edible fats; emulsifying agents, for
example lecithin, sorbitan monooleate, or acacia; non-aqueous
vehicles (which may include edible oils), for example almond oil,
fractionated coconut oil, oily esters such as esters of glycerine,
propylene glycol, or ethyl alcohol; preservatives, for example
methyl or propyl p-hydroxybenzoate or sorbic acid; and if desired
conventional flavouring or colouring agents.
For parenteral administration, fluid unit dosage forms are prepared
utilizing the compound and a sterile vehicle, and, depending on the
concentration used, can be either suspended or dissolved in the
vehicle. In preparing solutions the compound can be dissolved in
water for injection and filter sterilized before filling into a
suitable vial or ampoule and sealing. Advantageously, adjuvants
such as a local anaesthetic, a preservative and buffering agents
can be dissolved in the vehicle. To enhance the stability, the
composition can be frozen after filling into the vial and the water
removed under vacuum. Parenteral suspensions are prepared in
substantially the same manner, except that the compound is
suspended in the vehicle instead of being dissolved, and
sterilization cannot be accomplished by filtration. The compound
can be sterilized by exposure to ethylene oxide before suspending
in the sterile vehicle. Advantageously, a surfactant or wetting
agent is included in the composition to facilitate uniform
distribution of the compound.
The compositions may contain from 0.1% to 99% by weight, preferably
from 10-60% by weight, of the active material, depending on the
method of administration.
The invention also provides a method of treatment and/or
prophylaxis of dementia in mammals including humans, which
comprises administering to the sufferer an effective amount of a
compound of formula (I) or a pharmaceutically acceptable salt
thereof.
The dose of the compound used in the treatment of such disorders
will vary in the usual way with the seriousness of the disorders,
the weight of the sufferer, and the relative efficacy of the
compound. However, as a general guide suitable unit doses may be
0.05 to 100 mg, for example 0.2 to 50 mg and such unit doses may be
administered more than once a day, for example two or three times a
day, so that the total daily dosage is in the range of about 0.01
to 5 mg/kg and such therapy may extend for a number of weeks or
months.
Within the above indicated dosage ranges no toxicological effects
are indicated for the compounds of the invention.
In a further aspect the invention provides a compound of formula
(I) or a pharmaceutically acceptable salt thereof for use as an
active therapeutic substance.
The invention further provides a compound of formula (I) or a
pharmaceutically acceptable salt thereof, for use in the treatment
and/or prophylaxis of dementia.
In another aspect the invention provides the use of a compound of
formula (I) or a pharmaceutically acceptable salt thereof for the
preparation of a medicament for the treatment and/or prophylaxis of
dementia.
The following examples illustrate the invention and the following
descriptions illustrate the preparation of intermediates
thereto.
DESCRIPTION 1
(.+-.) 3-Cyano-1-azabicyclo[2.2.2]octane (D1) ##STR18##
A mixture of 3-quinuclidinone (12.5 g; 0.10 moles), tosylmethyl
isocyanide (25.4 g; 0.13 moles) and dry ethanol (10 ml; 0.17 moles)
in dry dimethoxyethane (350 ml) was cooled in ice and treated
portionwise with potassium t-butoxide (28.0 g; 0.25 moles) while
maintaining the temperature between 5.degree. C. and 10.degree. C.
After addition was complete the ice bath was removed and stirring
was continued for a further 30 min. The reaction was then heated at
40.degree. C. for 2.5 h. After cooling the precipitate was filtered
off and the flitrate concentrated in vacuo. Purification on neutral
alumina (Brockmann grade 1) using 2% methanol in ethyl acetate as
eluant afforded the title compound (D1) as a syrup (10.0 g; 74%)
which crystallised on cooling.
DESCRIPTION 2
(.+-.) 1-Azabicyclo[2.2.2]oct-3-yl-N-methoxycarboxamide (D2)
##STR19##
A solution of (.+-.) 3-cyano-1-azabicyclo[2.2.2]octane (D1) (15 g,
0.1103 mole) in concentrated hydrochloric acid (300 ml) was heated
under reflux for 4 h and then concentrated in vacuo to leave a
yellow gum. This was dissolved in methanolic hydrogen chloride (200
ml) and heated under reflux for 2 h, then concentrated in vacuo to
give an orange oil. This oil was treated with excess saturated
potassium carbonate solution and extracted with chloroform
(3.times.100 ml). The combined extracts were dried (Na.sub.2
SO.sub.4) and evaporated to give the methyl ester (18 g) as a
yellow oil. A solution of this ester (17.5 g, 0.956 mole) in 8M
hydrochloric acid (200 ml) was heater under reflux for 3 h. The
reaction was then concentrated in vacuo to a solid which was
dissolved in thionyl chloride (250 ml) and heated under reflux for
1 h when the copious evolution of sulphur dioxide and hydrogen
chloride ceased. The reaction was then concentrated in vacuo to a
gum, which was freed from excess thionyl chloride by co-evaporation
with toluene. The residue was dissolved in dry acetonitrile (700
ml) under an atmosphere of nitrogen and treated with methoxylamine
hydrochloride (8.14 g, 0.0975 mole). After cooling to 0.degree. C.
triethylamine (40.8 ml, 0.293 mole) was added dropwise over 0.5 h
and the mixture was stirred at 0.degree. C. for 3 h. Triethylamine
hydrochloride was removed by filtration, the solvent was removed in
vacuo and the residue partitioned between saturated aqueous
potassium carbonate solution (200 ml) and chloroform (5.times.150
ml). The combined organic extracts were dried (Na.sub.2 SO.sub.4)
and evaporated to a gum, which was chromatographed on neutral
alumina using 1-10% methanol/chloroform as eluant to afford the
title compound (D2) (8.28 g, 54%) as a semi-crystalline solid.
.sup.1 H NMR (CDCl.sub.3) .delta.: 1.41 (1H, m), 1.63 (2H, m), 1.95
(2H, m), 2.70-3.12 (6H, m), 3.35 (1H, m), 3.76 (3H, s), 6.6 (1H,
br).
DESCRIPTION 3
(.+-.) Ethyl 1-(2-chloroethyl)-3-piperidylcarboxylate (D3)
##STR20##
A solution of ethyl 3-piperidylcarboxylate (100 g, 0.64 mole) in
acetone (800 ml) was treated with 1-bromo-2-chloroethane (106.5 ml,
1.28 mole) and anhydrous potassium cabonate (138 g, 1.00 mole) and
the mixture stirred at room temperature for 24 h. The mixture was
concentrated in vacuo and the residue treated with water (300 ml)
and extracted with ether (2.times.200 ml). The combined ether
extracts were dried (Na.sub.2 SO.sub.4) and concentrated in vacuo
to leave a yellow oil, which was purified by chromatograpny on
silica gel eluting with 50% ether/60-80 petrol to give the title
compound (D3) as a pale yellow oil (78.2 g, 56%).
.sup.1 H Nmr (CDCl.sub.3) .delta.1.25 (3H, t, J=7Hz), 1.40-3.10
(11H, m), 3.58 (2H, t, J=7 Hz), 4.15 (2H, q, J=7Hz)
DESCRIPTION 4
(.+-.) Ethyl 1-azabicyclo[3.2.1]oct-5-ylcarboxylate (D4)
##STR21##
A solution of diisopropylamine (33.6 ml, 0.24 mole) in dry ether
(1500 ml) at -65.degree. C. under nitrogen was treated with 1.5M
n-butyllithium in hexane (150 ml, 0.225 mole) and the solution
stirred for 15 mins, before adding
N,N,N',N'-tetramethylethylenediamine (68 ml, 0.45 mole). After
stirring for a further 15 mins, the solution was treated with a
solution of ethyl 1-(2-chloroethyl)-3-piperidylcarboxylate (D3,
44.7 g, 0.204 mole) in dry ether (100 ml) and the mixture allowed
to warm up to room temperature over 2 h. The reaction mixture was
treated with potassium carbonate solution (300 ml) and the ether
layer separated, dried (Na.sub.2 SO.sub.4) and concentrated in
vacuo to leave an orange oil. This was purified by chromatography
on silica gel eluting with 10% methanol/chloroform to give the
title compound (D4) as a yellow oil (31.9, 84%), b.p.
120.degree.-130.degree. C..sub.0.4mmHg (Kugelrohr apparatus).
.sup.1 H Nmr (CDCl.sub.3) .delta.1.25 (3H, t, J=7Hz), 1.10-2.20
(6H, m), 2.60-3.25 (6H, m), 4.20 (2H, q, J=7Hz)
DESCRIPTION 5
(.+-.) 1-Azabicyclo[3.2.1]oct-5-yl-N-methoxy-N-methylcarboxamide
(D5) ##STR22##
(.+-.) Ethyl-1-azabicyclo[3.2.1]oct-5-ylcarboxylate (D4, 5 g, 0.027
mole) in hydrochloric acid (5N, 150 ml) was heated under reflux for
1.5 h. The reaction was then concentrated in vacuo to a hygroscopic
solid which was dissolved in thionyl chloride (100 ml) and heated
under reflux for 0.5 h. The mixture was then concentrated in vacuo
to a gum, which was freed from excess thionyl chloride by
co-evaporation with toluene. The residue was dissolved in absolute
chloroform (100 ml) and treated with N,O-dimethylhydroxylamine
hydrochloride (2.92 g, 0.030 mole). After cooling to 0.degree. C.
pyridine (10.9 ml, 0.135 mole) was added dropwise. The reaction was
allowed to warm to room temperature and stirred for 1 h. The
reaction mixture was poured into saturated aqueous potassium
carbonate solution (100 ml) and the mixture was extracted with
chloroform (4.times.100 ml). The combined organic extracts were
dried (Na.sub.2 SO.sub.4) and evaporated to give an oil which was
distilled in vacuo to afford the title compound (D5) (3.77 g, 69%)
b.p. 160.degree. C. at 0.5 mmHg.
.sup.1 H Nmr (CDCl.sub.3) .delta.: 1.47 (1H, m), 1.68-2.13 (7H, m),
2.78-3.15 (6H, m), 3.17 (3H, s), 3.67 (3H, s).
DESCRIPTION 6
(.+-.) 1-Azabicyclo[3.2.1]oct-5-yl trimethylsilylethynyl ketone
(D6) ##STR23##
n-Butyllithium (7.3 ml of a 1.6M solution in hexane, 0.0117 mole)
was added dropwise to (trimethylsilyl)acetylene (1.57 ml, 0.0111
mole) in dry THF (50 ml) at -70.degree. C. The resulting solution
was stirred at -70.degree. C. for 0.5 h then added dropwise by
cannula to (.+-.)
1-azabicyclo[3.2.1]oct-5-yl-N-methoxy-N-methylcarboxamide (D5, 1.83
g, 0.0092 mole) in dry THF (50 ml) at -70.degree. C. The mixture
was allowed to warm to -50.degree. C., stirred at this temperature
for 1 h, then poured into ice-cold 1M hydrochloric acid. After 15
mins at 0.degree. C. the mixture was made just basic by addition of
potassium carbonate and extracted with chloroform (3.times.100 ml).
The combined extracts were dried (Na.sub.2 SO.sub.4) and evaporated
to give the title compound (D6) as a clear mobile oil (1.65 g,
76%).
.sup.H Nmr (CDCl.sub.3) .delta.: 0.24 (9H, s), 1.00-1.91 (5H, m),
2.29 (1H, m), 2.70-3.28 (6H, m).
DESCRIPTION 7
(.+-.) 1-Azabicyclo[3.2.1]oct-5-yl -trimethylsilylethynyl
ketone-O-methyloxime (D7) ##STR24##
1-Azabicyclo[3.2.1]oct-5-yl trimethylsilylethynyl ketone (D6, 0.85
g, 0.0036 mole) was added to a mixture of methanol (50 ml) and
glacial acetic acid (1.5 ml). Methoxylamine hydrochloride (0.36 g,
0.0043 mole) was added and the reaction mixture stirred at room
temperature for 18 h then evaporated under reduced pressure.
Saturated potassium carbonate (25 ml) was added to the residue and
the mixture was extracted with chloroform (4.times.50 ml). The
combined organic extracts were dried (Na.sub.2 SO.sub.4) and
evaporated to give the title compound (D7) as a 6:1 mixture of cis
and trans oxime ethers (0.77 g, 81%).
.sup.1 H Nmr (major isomer, CDCl.sub.3): 0.25 (9H, s), 1.53 (1H,
m), 1.68-1.95 (4H, m), 2.07 (1H, m), 2.72-3.16 (6H, m), 3.96 (3H,
s).
.sup.13 C Nmr (major isomer, CDCl.sub.3): -0.29, 19.77, 34.49,
35.02, 47.61, 52.08, 54.57, 62.45, 63.47, 93.86, 107.40, 145.41
DESCRIPTION 8
(.+-.) 1-Azabicyclo[3.2.1]oct-5-yl-N-methoxycarboxamide (D8)
##STR25##
(.+-.) Ethyl-1-azabicyclo[3.2.1]oct-5-ylcarboxylate (D4, 7.33 g,
0.040 mole) in hydrochloric acid (8N, 100 ml) was heated under
reflux for 4 h and then concentrated in vacuo to give a white solid
which was dissolved in thionyl chloride (100 ml) and heated under
reflux for 1.5 h. The mixture was concentrated in vacuo to a gum,
which was freed from excess thionyl chloride by co-evaporation with
toluene. The residue was dissolved in dry acetonitrile (200 ml) and
methoxylamine hydrochloride (3.51 g, 0.042 mole) was added. After
cooling to -20.degree. C., triethylamine (27.9 ml, 0.200 mole) was
added dropwise over 0.5 h and the reaction mixture was allowed to
warm to room temperature overnight. The solvent and excess
triethylamine were removed in vacuo and the residue was partitioned
between saturated aqueous potassium carbonate solution (100 ml) and
chloroform (5.times.100 ml). The combined organic extracts were
dried (Na.sub.2 SO.sub.4) and evaporated to a gum, which was
chromatographed on neutral alumina using 3-15% methanol/chloroform
as eluant to afford the title compound (D8) (2.86 g, 39%) as a
low-melting solid.
.sup.1 H Nmr (CDCl.sub.3) .delta.: 1.55 (1H, m), 1.67-2.00 (4H, m),
2.12 (1H, m), 2.73-3.01 (5H, m), 3.12 (1H, m), 3.76 (3H, s), 5.60
(1H, broad).
DESCRIPTION 9
(.+-.) exo-Ethyl 1-azabicyclo[2.2.1]hept-3-ylcarboxylate (D9)
##STR26##
(.+-.) exo-Ethyl
1-benzyl-1-azoniabicyclo[2.2.1]hept-3-yl-carboxylate bromide (EP A
No. 0257741 Description 9) (54 g 0.16 mole) was dissolved in
ethanol (400 ml) and hydrogenated over 10% Pd-C (8.5 g) at
atmospheric pressure and 25.degree. C. After 2 h the solution was
filtered and concentrated in vacuo to leave a gum. This was
partitioned between chloroform and saturated aqueous potassium
carbonate solution and the organic phase separated, dried (Na.sub.2
SO.sub.4) and concentrated in vacuo to leave a gum. This gum was
distilled to give the title compound (D9) as a colourless oil (23
g, 85%) b.p. 150.degree. C. at 0.5 mmHg.
.sup.1 H Nmr (CDCl.sub.3) .delta.: 1.10-1.20 (1H, m), 1.25 (3H, t,
J=7Hz), 1.54-1.67 (.sup.1 H, m), 2.15-2.25 (1H, m), 2.28-2.35 (1H,
m), 2.38-2.50 (1H, m), 2.60-2.67 (1H, m), 2.70-2.90 (3H, m),
2.93-3.03 (1H, m), 4.13 (2H, q, J=7Hz).
DESCRIPTION 10
(.+-.) exo-1-Azabicyclo[2.2.1]hept-3-yl-N-methoxycarboxamide (D10)
##STR27##
(.+-.) exo-Ethyl-1-azabicyclo[2.2.1]hept-3-ylcarboxylate (D9, 1 g,
0.0059 mole) was converted to the acid chloride hydrochloride salt
and treated with methoxylamine hydrochloride (0.54 g, 0.0065 mole)
and triethylamine as in the method of Description 8 to give the
title compound (D10) (0.40 g, 40%) as a low melting solid.
.sup.1 H Nmr (CDCl.sub.3) .delta.: 1.18 (1H, m), 1.63 (1H, m),
2.40-2.58 (2H, m), 2.63-2.98 (5H, m), 3.06 (1H, m), 3.73 (3H,
s).
DESCRIPTION 11
N-Benzyl-N-[(trimethylsilyl)methyl]amine (D11) ##STR28##
A mixture of chloromethyltrimethylsilane (325 g, 370 ml, 2.65 mole)
and benzylamine (835 g, 850 ml, 7.78 mole) was heated at
120.degree.C. (oil bath temperature) for 2 h. A white solid began
appearing after only 10 minutes and a viscous mixture eventually
resulted. The reaction mixture was allowed to cool, then basified
with potassium carbonate solution and extracted twice with ether.
The combined extracts were dried (Na.sub.2 SO.sub.4) and
concentrated in vacuo to leave a yellow oil, which was purified by
distillation. The excess benzylamine was removed in the first
fractions (b.p. 47.degree.-62.degree.C. at 2 mmHg). The title
compound (D11) was obtained as a colourless oil (380 g, 74%) b.p.
75.degree.-80.degree.C. at 2 mmHg.
.sup.1 H Nmr (CDCl.sub.3) .delta.: 0.10 (9H, s), 1.40 (1H, br.s,
NH), 2.10 (2H, s), 3.85 (2H, s), 7.27-7.43 (5H, m)
DESCRIPTION 12
N-Benzyl-N-(methoxymethyl)-N-[(trimethylsilyl)methyl]amine (D12)
##STR29##
A stirred 37% aqueous formaldehyde solution (230 g, 215 ml, 2.8
mole) was cooled to -5.degree. C. and treated dropwise over 20
minutes with N-benzyl-N-[(trimethylsilyl)methyl]amine (D11, 380 g,
1.96 mole), whilst keeping the temperature between -5.degree. and
0.degree. C. After completing the addition, the mixture was treated
with methanol (230 ml), saturated with potassium carbonate and
stirred at room temperature for 2 h. The mixture was treated with
ether (500 ml) and the organic phase separated, dried (K.sub.2
CO.sub.3) and concentrated in vacuo to give a colourless oil (480
g), which was about 75% title compound (D12). This material was
used in the next stage without purification.
.sup.1 H Nmr (CDCl.sub.3) .delta.: 0.10 (9H, s), 2.23 (2H, s), 3.30
(3H, s), 3.82 (2H, s), 4.05 (2H, s), 7.25-7.40 (5H, m)
DESCRIPTION 13
.alpha.-Formyl-.gamma.-butyrolactone sodium salt (D13)
##STR30##
A stirred suspension of sodium hydride (300 g of 80% oil
dispersion, 10 moles) in dry ether (8l) under nitrogen was treated
slowly with absolute ethanol (60 ml, 1.1 mole), followed
immediately by a mixture of ethyl formate (808 ml, 10 moles) and
.gamma.-butyrolactone (770 ml, 10 moles) over about 1.25 h. The
rate of addition of the reagents was regulated to give a steady
reflux and evolution of hydrogen (about 220 l). After completing
the addition, the mixture was stirred for a further 0.5 h and the
solid then filtered off, washed with ether and dried in vacuo to
give the title compound (D13) as a white solid (1.32 kg, 97%).
DESCRIPTION 14
.alpha.-Methylene-.gamma.-butyrolactone (D14) ##STR31##
A stirred suspension of paraformaldehyde (270 g, 9.0 mole) in THF
(3.5 L) at room temperature in a 20 L flask under nitrogen was
treated with .alpha.-formyl-.gamma.-butyrolactone sodium salt (D13,
270 g, 2.0 mole). The mixture was then immediately heated to reflux
temperature for 1 h. Evolution of a small quantity of gas was
observed. The mixture was cooled to around 10.degree. C., treated
with saturated aqueous potassium carbonate solution (500 ml) and
ether (1.5 L), and the organic layer separated, dried (Na.sub.2
SO.sub.4) and concentrated in vacuo to leave a pale yellow oil.
This material was distilled to give the title compound (D14) as a
colourless oil (125 g, (64%) b.p. 76.degree.-80.degree. C. at 8
mmHg.
.sup.1 H Nmr (CDCl.sub.3) .delta.: 2.95-3.03 (2H, m), 4.40 (2H, t,
J=7Hz), 5.69 (1H, t, J=3Hz), 6.25 (1H, t, J=3Hz)
DESCRIPTION 15
(.+-.)-7-Benzyl-7-aza-2-oxaspiro[4.4]nonan-1-one (D15)
##STR32##
A stirred solution of
N-benzyl-N-(methoxymethyl)-N-[(trimethylsilyl)methyl]amine (D12,
160 g of 75% purity, assume 0.51 mole) and
.alpha.-methylene-.gamma.- butyrolactone (D14, 50 g, 0.51 mole) in
dichloromethane (11 L) under nitrogen was cooled to 0.degree. C.
and then treated with a 1M solution of trifluoroacetic acid in
dichloromethane (50 ml, 0.05 mole), keeping the temperature below
5.degree. C. The reaction mixture was allowed to warm to room
temperature over 2 h, then washed with saturated sodium bicarbonate
solution. The aqueous wash was extracted with dichloromethane and
the organic solutions then combined, washed with brine, dried
(Na.sub.2 SO.sub.4) and concentrated in vacuo to leave a pale
yellow oil. This was distilled in vacuo to give the title compound
(D15) as a colourless oil (96 g, 81%) b.p. 160.degree.-170.degree.
C. at 1 mmHg.
.sup.1 H Nmr (CDCl.sub.3) .delta.: 1.77-1.92 (1H, m), 2.15-2.40
(3H, m), 2.48-2.78 (3H, m), 2.85-2.98 (1H, m), 3.55-3.70 (2H, m),
4.10-4.30 (2H, m), 7.15-7.35 (5H, m)
DESCRIPTION 16
Ethyl 1-benzyl-1-azoniabicyclo[2.2.1]hept-4-ylcarboxylate bromide
(D16) ##STR33##
A stirred solution of 7-benzyl-7-aza-2-oxaspiro[4.4]nonan-1-one
(D15, 96 g, 0.42 mole) in ethanol (150 ml) was saturated with
hydrogen bromide gas and then left to stand for 18 h. The solution
was concentrated in vacuo and the residue basified with saturated
potassium carbonate solution and extracted with chloroform. The
organic extract was dried (Na.sub.2 SO.sub.4) and concentrated in
vaeuo to leave a pale brown oil. This was treated with ether and
the resulting solid filtered off, washed with ether and dried to
give the title compound (D16) as a white solid (130 g, 91%).
DESCRIPTION 17
Ethyl 1-azabicyclo[2.2.1]hept-4-ylcarboxylate hydrobromide salt
(D17) ##STR34##
A suspension of ethyl
1-benzyl-1-azoniabicyclo[2.2.1]hept-4-ylcarboxylate bromide (D16,
130 g, 0.38 mole) in ethanol (500 ml) was hydrogenated over 10%
palladium on charcoal catalyst (8 g) at atmospheric temperature and
pressure for 18 h. The catalyst was removed by filtering through
celite, washing several times with hot ethanol, and the filtrate
concentrated in vacuo to give the title compound (D17) as a
crystalline white solid (80.1 g, 84%).
.sup.1 H Nmr (CD.sub.3 OD) .delta.: 1.3 (3H, t, J=7Hz), 2.0-2.18
(2H, m), 2.3-2.5 (2H, m), 3.35-3.5 (2H, m), 3.45 (2H, s), 3.5-3.7
(2H, m), 4.25 (2H, q, J=7Hz)
DESCRIPTION 18
1-Azabicyclo [2.2.1 ]hept-4-yl-N-methoxycarboxamide (D18)
##STR35##
Ethyl 1 -azabicyclo[2.2.1]hept-4-ylcarboxylate hydrobromide salt
(D17, 16.85 g, 0.067 mole) was converted to the acid chloride
hydrochloride salt and treated with methoxylamine hydrochloride
(6.19 g, 0.074 mole) and triethylamine as in the method of
Description 8 to give the title compound (D18) as a pale brown
crystalline solid (4.60 g, 40%) m.p. 129.degree.-134.degree. C.
.sup.1 H Nmr (CDCl.sub.3) .delta.: 1.48 (2H, m), 1.97 (2H, m), 2.66
(4H, m), 3.05 (2H, m), 3.80 (3H, s).
DESCRIPTION 19
(.+-.) 1-Azabicyclo[2.2.2oct-3-yl cyclopropyl ketone (D19)
##STR36##
(.+-.) 3-Cyano-1-azabicyclo[2.2.2]octane (D1) (5 g, 0.0368 mole)
was converted to the acid chloride hydrochloride salt as in the
method of Description 2. To a mixture of this material (1 g, 0.0048
mole) and cyclopropyltrimethylsilane* (0.54 g, 0.0047 mole) in
dichloromethane (100 ml) at room temperature was added aluminium
chloride (1.27 g, 0.0095 mole) in portions with cooling. After
stirring at room temperature for 16 h the reaction mixture was
poured into saturated potassium carbonate (75 ml) and extracted
with chloroform (3.times.75 ml). The combined extracts were dried
(Na.sub.2 SO.sub.4) and evaporated to an oil which was
chromatographed on silica gel using 10% methanol/chloroform as
eluant to give the ketone (D19) as a pale yellow oil (0.16 g,
19%).
.sup.1 H Nmr (CDCl.sub.3) .delta.: 0.76-1.06 (4H, m), 1.33 (2H, m),
1.62 (2H, m), 1.89 (1H, m), 2.60-2.92 (6H, m), 3.22-3.49 (2H,
m).
.sup.13 C Nmr (CDCl.sub.3) .delta.: 10.60, 10.92, 19.83, 22.14,
24.17, 27.12, 46.93, 47.17, 47.93, 49.89, 211.37
DESCRIPTION 20
(.+-.) cis-2-Benzyl-hexahydropyrano[3,4-c]pyrrole-4(1H)-one (D20)
##STR37##
To a stirred solution of 5,6-dihydro-2H-pyran-2-one* (136 g, 1.39
mole) in dichloromethane (2 L) at -20.degree. C. was added
N-benzyl-N-(methoxymethyl)-N-trimethylsilylmethyl amine (80% pure)
(D12, 450 g, 1.5 mole). To this solution was added trifluoroacetic
acid in dichloromethane (140 ml, 1 molar solution) at -20.degree.
C. The reaction was then transferred at -20.degree. C. under a
small positive pressure of nitrogen via a double ended needle to a
second flask on a water bath at 30.degree. C. As the cold mixture
warmed up an exothermic reaction occurred and the rate of addition
was controlled to maintain gentle reflux. When addition was
complete and the reaction had subsided the solution was allowed to
stand at room temperature for 2 h. The reaction was then washed
with saturated aqueous potassium carbonate solution, dried
(Na.sub.2 SO.sub.4) and concentrated in vacuo to a gum. Vacuum
distillation afforded the title compound as a single main fraction
b.p. 180.degree.-190.degree. C. .sub.0.5mmHg (D20, 180.9 g, 0.73
mole, 56%).
.sup.1 H NMR (CDCl.sub.3) .delta.: 1.55-1.72 (1H, m), 1.95-2.10
(1H, m), 2.23-2.34 (1H, m), 2.63-3.0 (4H, m), 3.05-3.2 (1H, m),
3.55 and 3.65 each (1H, d, J=12Hz), 4.22 (1H, t, J=12Hz), 4.35-4.48
(1H, m), 7.30 (5H, brs).
.sup.13 C NMR CDCl.sub.3 .delta.: 28.4, 35.1, 42.1, 57.5, 59.6,
60.2, 67.2, 127.2, 128.4, 128.7, 138.6, 173.3
DESCRIPTION 21
(.+-.) endo
Ethyl-1-azabicyclo[2.2.1]hept-3-ylcarboxylate (D21) ##STR38##
(.+-.) cis-2-benzyl-hexahydropyrano[3,4-c]pyrrole-4(1H)-one (D20)
(180 g, 0.78 mole) in ethanol (400 ml) was stirred and cooled to
0.degree. C. and hydrogen bromide gas introduced at such a rate
that the temperature did not rise above 20.degree. C. until the
solution was saturated. The reaction was allowed to stand at room
temperature for 6 h. The reaction was then poured into a well
stirred mixture of chloroform (2 L) and saturated aqueous potassium
carbonate solution (1.5 L) which was cooled by the addition of
solid carbon dioxide. The organic layer was separated and the
aqueous layer extracted with chloroform (4.times.1 L). The combined
organic extracts were dried (Na.sub.2 SO.sub.4) concentrated in
vacuo to a gum. The gum was then stirred with ether (3.times.750ml)
to remove any unreacted starting material and the ether insoluble
gum dissolved in ethanol (1 L). Palladium on charcoal 10% (20 g)
was then added and the mixture stirred under an atmosphere of
hydrogen at 50.degree. C. for 6 h when the uptake of hydrogen was
complete. The reaction was then filtered through Kieselguhr and
concentrated in vacuo to a gum. This was partitioned between
chloroform and saturated aqueous potassium carbonate solution. The
organic phase was separated, dried over sodium sulphate and
concentrated in vacuo to a gum. Distillation in vacuo afforded the
title compound (D21, 75 g, 0.44 mole, 56%) as an oil b.p.
90.degree.-95.degree. C..sub.0.5mmHg
.sup.1 H NMR (CDCl.sub.3) .delta.: 1.28 (3H, t, J=8Hz), 1.3-1.45
(1H, m), 1.5-1.65 (1H, m), 2.5-2.7 (3H, m), 2.85-3.05 (5H, m), 4.15
(2H, q, J=8Hz)
.sup.13 C NMR CDCl.sub.3 .delta.: 14.2 (CH.sub.3), 25.3 (C-5), 40.9
and 46.3 (C-3 and C-4), 53.2, 55.7, 60.5, 61.2 (C-2, C-6, C-7,
CH.sub.2 O), 173.2 (C.dbd.O)
DESCRIPTION 22
(.+-.) exo- and
endo-1-Azabicyclo[2.2.1]hept-3-ylcarbonyl chloride
hydrochloride salt (D22) ##STR39##
(.+-.) endo-Ethyl-1-azabicyclo[2.2.1]hept-3-yl carboxylate (D21)
(4.0 g, 0.02 mole) in ethanol (20 ml) was added to a refluxing
solution of sodium ethoxide prepared by adding sodium (0.4 g, 0.017
mole) to ethanol (80 ml). The mixture was heated under reflux for 4
h, cooled and evaporated to dryness to give a mixture of the exo
and endo esters (D9) and (D21) in the ratio of 7:2. This was
treated with hydrochloric acid (5N, 100 ml) and then thionyl
chloride (50 ml) as in the method of Description 8 to yield a
mixture of the title compounds (D22) as a yellow oil (4.7 g,
100%).
DESCRIPTION 23
(.+-.)
endo-1-Azabicyclo[2.2.1]hept-3-yl-N-methoxycarboxamide (D23)
##STR40##
(.+-.) endo-Ethyl-1-azabicyclo[2.2.1]hept-3-yl carboxylate (D21)
(3.0 g, 0.018 mole) was converted to the acid chloride
hydrochloride salt and treated with methoxylamine hydrochloride
(1.42 g, 0.017 mole) and pyridine as in the method of Description 8
to give the title compound (D23) (2.00 g, 66%) as a low melting
solid.
.sup.1 H NMR (CDCl.sub.3) .delta.: 1.40-1.65 (2H, m), 2.49-3.05
(9H, m), 3.77 (3H, s).
When a mixture of (.+-.) exo and
endo-1-azabicyclo[2.2.1]hept-3-ylcarbonyl chloride hydrochloride
salt (D22, 4.76 g, 0.02 mole) was employed in the above reaction
the product was a 7:2 mixture (3.15 g, 78%) of the exo and endo
N-methoxycarboxamide (D10) and (D23).
DESCRIPTION 24
(.+-.)
exo-1 -Azabicyclo[2.2.1]hept-3-yl-N-ethoxycarboxamide (D24)
##STR41##
(.+-.) exo and endo-1-Azabicyclo[2.2.1]hept-3-ylcarbonyl chloride
hydrochloride salt (D22) (4.66 g, 0.024 mole) was treated with
ethoxylamine hydrochloride (2.4 g, 0.024 mole) and pyridine as in
the method of Description 8 to give the title compound (D24) (2.0
g, 46%) as an oil. The endo isomer was not isolated.
.sup.1 H NMR (CDCl.sub.3) .delta.: 1.05-1.22 (1H, m), 1.28 (3H, t,
J=7Hz), 1.55-1.71 (1H, m), 2.28-3.12 (9H, m), 3.93 (2H, q, J
=7Hz)
DESCRIPTION 25
(.+-.) exo and
endo-1-Azabicyclo[2.2.1]hept-3-yl-N-prop-2-ynyloxycarboxamide (D25)
##STR42##
(.+-.) exo and endo-1-Azabicyclo[2.2.1]hept-3-ylcarbonylchloride
hydrochloride salt (D22) (11.8 g, 0.06 mole) was treated with
propargyloxylamine* hydrochloride (6.5 g, 0.06 mole) and pyridine
as in the method of Description 8 to give the title compounds (D25)
as a 7:2 mixture of exo and endo isomers (2.02 g, 16%).
DESCRIPTION 26
(.+-.) endo-1-Azabicyclo[2.2.1]hept-3-ylcyclopropyl ketone (D26)
##STR43##
(.+-.) endo-Ethyl-1-azabicyclo[2.2.1]hept-3-ylcarboxylate (D21, 4
g, 23.7 mmole) was converted to the acid chloride hydrochloride
salt as in the method of Description 2. To a mixture of this
material (4.6 g, 23.7 mmole) and cyclopropyltrimethylsilane (1.92
g, 35 mmole) in dry dichloromethane (250 ml), under nitrogen,
cooled in ice, was added aluminium chloride (7.89 g, 59 mmole) in
portions. After refiuxing for 17 h, the reaction mixture was cooled
on ice, treated with saturated aqueous potassium carbonate (50 ml)
and water (50 ml). The aqueous and organic phases were separated,
and the aqueous phase extracted with chloroform (3.times.200 ml).
The combined organic extracts were dried (Na.sub.2 SO.sub.4) and
evaporated to an oil which was chromatographed on silica gel in a
gradient of 0-20% methanol in chloroform to afford the title
compound (D26) as an oil (0.13 g, 3%).
DESCRIPTION 27
(.+-.) exo- and
endo-3-Oxo-3-(1-azabicyclo[2.2.1]hept-3-yl)propionitrile lithium
salt (D27) ##STR44##
A solution of diisopropylnmine (0.35 g, 5.92 mmole) in
tetrahydrofuran (20 ml), under nitrogen, was cooled to -78.degree.
C. then treated with n-butyl lithium (3.7 ml of a 1.6M solution in
hexane, 5.92 mmole) and N,N,N',N'- tetramethylethylenediamine (0.69
g, 5.92 mmole). The solution was allowed to warm up to -20.degree.
C. over about five minutes, then cooled back down to -78.degree.
C.
The solution was treated with acetonitrile (0.24 g, 5.92 mmole),
then after fifteen minutes treated with (.+-.)
endo-ethyl-1-azabicyclo[2.2.1]hept-3-ylcarboxylate (D21, 0.5 g,
2.95 mmole) in tetrahydrofuran (2 ml). After 0.5 h the solution was
concentrated in vacuo to afford the title compound (D27) as a beige
solid (1.5 g) which was used without further purification.
EXAMPLE 1
(.+-.)
1-Azabicyclo[2.2.2]oct-3-yl-N-methoxycarboximidoyl
chloride oxalate salt (E1) ##STR45##
(.+-.) 1-Azabicyclo[2.2.2]oct-3-yl-N-methoxycarboxamide (D2, 2.77
g, 0.0151 mole) in nitromethane (50 ml) was treated with
phosphorous pentachloride at -10.degree. C. After 0.25 h the
reaction mixture was poured into saturated aqueous potassium
carbonate solution (30 ml) and extracted with chloroform
(4.times.50 ml). The combined extracts were dried (Na.sub.2
SO.sub.4) and evaporated to give an oil which was chromatographed
on neutral alumina using 1% methanol/chloroform as eluant to yield
the imidoyl chloride as a mobile oil (0.853 g, 28%).
.sup.1 H Nmr (CDCl.sub.3) .delta.: 1.42 (1H, m), 1.68 (3H, m), 2.23
(1H, m), 2.63-2.96 (5H, m), 3.05 (1H, dt, J=10Hz, 1Hz), 3.35 (1H,
dd, J=10Hz, 5Hz), 3.98 (3H, s).
.sup.13 C Nmr (CDCl.sub.3) .delta.: 21.62, 25.03, 27.33, 44.69,
47.41, 47.49, 50.62, 63.10, 140.82.
Ir (film) 1660, 1040 cm.sup.-1.
A portion of this material was converted to the oxalate salt which
was recrystallised from methanol/acetone to give the title compound
(E1) as a white crystalline solid. m.p. 143.degree.-146.degree.
C.
.sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.73 (2H, m), 1.92 (2H, m),
2.39 (1H, m), 3.08-3.30 (5H, m), 3.46 (2H, m), 3.94 (3H, s).
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 18.26, 22 58, 23.27, 40.79,
45.14, 45.22, 47.19, 62.77, 137.95.
Analysis C.sub.9 H.sub.15 N.sub.2 OCl.C.sub.2 H.sub.2 O.sub.4
requires C: 45.14; H: 5.85; N: 9.57; found C: 45.08; H: 5.84; N:
9.74
EXAMPLE 2
(.+-.)
1-Azabicyclo2.2.2]oct-3-yl-N-methoxycarboximidic acid methyl ester
oxidate salt (E2) ##STR46##
(.+-.) 1-Azabicyclo[2.2.2]oct-3-yl-N-methoxycarboximidoyl chloride
(E1) (0.063 g, 0.0031 mole) in dry methanol (10 ml) was treated
with sodium methoxide (0.0252 g, 0.0047 mole) at reflux for 48 h.
The reaction mixture was concentrated in vacuo and the residue
partitioned between saturated aqueous potassium carbonate solution
(15 ml) and chloroform (5.times.50 ml). The combined organic
extracts were dried (Na.sub.2 SO.sub.4) and evaporated to an oil,
which was chromatographed on neutral alumina using 2-20%
methanol/chloroform to afford 3-cyano-1-azabicyclo[2.2.2]octane
(0.097 g, 23%, spectral properties identical to D1) and the acid
ester as a gum (0.129 g, 21%).
.sup.1 H Nmr (CDCl.sub.3) .delta.: 1.52 (.sup.1 H, m), 1.77 (2H,
m), 1.94 (1H, m), 2.12 (1H, m), 2.66 (1H, m), 2.85-3.15 (5H, m),
3.40 (1H, dd, J=10Hz, 5Hz), 3.78 (3H, s), 3.92 (3H, s).
.sup.13 C Nmr (CDCl.sub.3) .delta.: 21.03, 24.27, 26 29, 37.10,
46.97, 47.19, 49.43, 58.70, 62.58, 155.48.
MS (CI) M.sup.+ +1-199.
A portion of this material was converted to the oxalate salt which
was recrystallised from methanol/acetone to give the title compound
(E2) as a white crystalline solid. m.p. 90.degree.-93.degree.
C.
.sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.61-1.93 (4H, m), 2.19 (1H,
m), 3.00-3.23 (5H, m), 3.34 (2H, m), 3.68 (3H, s), 3.85 (3H,
s).
.sup.13 C Nmr (d.sub.6 DMSO) 4: 18.49, 22.61, 22.76, 34.13, 45.08,
45.38, 47.04, 57.87, 61.60, 154.18.
Analysis C.sub.10 H.sub.18 N.sub.2 O.sub.2.C.sub.2 H.sub.2 O.sub.4
requires C: 49.99; H: 6.99; N: 9.72; found C: 49.92; H: 7.09; N:
9.62
EXAMPLE 3
(.+-.)
.alpha.-(Methoxyimino)-.alpha.-(1-azabicyclo[2.2.2]oct-3-yl)acetonitrile
hydrochloride salt (E3) ##STR47##
(.+-.) 1-Azabicyclo[2.2.2oct-3-yl-N-methoxycarboximidoyl chloride
(E1) (0.067g, 0.33 mmol) in dry DMSO (5 ml) was treated with sodium
cyanide (0.019 g, 0.40 mmol) at 100.degree. C. for 5 h. The solvent
was evaporated in vacuo and the residue partitioned between
saturated aqueous potassium carbonate solution (10 ml) and
chloroform (5.times.30 ml). The combined organic extracts were
dried (Na.sub.2 SO.sub.4) and evaporated to an oil, which was
chromatographed on silica using 7% methanol/chloroform to afford
3-cyano-1-azabicyclo[2.2.2]octane (0.008 g, 19%, spectral
properties identical to D1) and the imidoyl cyanide as
crystallising oil (0.016 g, 27%).
.sup.1 H Nmr (CDCl.sub.3) .delta.: 1.46 (1H, m), 1.56-1.77 (3H, m),
2.14 (1H, m), 2.62-3.00 (5H, m), 3.06 (1H, dt, J=10Hz, 1Hz), 3.27
(1H, dd, J=10Hz, 5Hz), 4.01 (3H, S).
.sup.13 C Nmr (CDCl.sub.3) .delta.: 20.79, 25.01, 26.59, 39.22,
46.90, 47.00, 48.87,
A portion of this material was converted to the hydrochloride salt
which was recrystallised from acetone/ether to give the title
compound (E3) as a white crystalline solid. m.p.
176.degree.-182.degree. C.
.sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.63-2.02 (4H, m), 2.32 (1H,
m), 3.01-3.67 (7H, m), 4.07 (3H, s).
.sup.13 C Nmr (D.sub.6 DMSO) .delta.: 18.1, 22.7, 23.3, 35.9, 44.9,
45.2, 46.2, 64.0, 109.9, 131.7
Analysis: C.sub.10 H.sub.15 N.sub.3 O.HCl requires C: 52.29; H:
7.02; N: 18.29; found: C: 51.98; H: 7.10; N: 18.33
EXAMPLE 4
(.+-.) 1-Azabicyclo[3.2.1]oct-5-yl ethynyl ketone
O-methyloxime oxalate salt (E4) ##STR48##
Aqueous 12M sodium hydroxide (15 ml) at 0.degree. C. was added to a
mixture of 1-azabicyclo[3.2. ]oct-5-yl trimethylsilylethynyl ketone
O-methyloxime (D7, 0.63 g, 0.0024 mole) and triethylbenzylamine
bromide (0.22 g, 0.80 mole) in acetonitrile (15 ml) at 0.degree. C.
The reaction mixture was stirred at 0.degree. C. for 10 minutes
then diluted with ether (100 ml). The organic phase was separated,
dried (Na.sub.2 SO.sub.4), and evaporated. The residue was taken-up
in dry ether (200 ml) and filtered through Kieselguhr, then
evaporated to give the ethynyl oxime as a pale yellow oil. This
material was converted to the oxalate and recrystallised from
acetone to yield the title compound (E4) as a 6:1 mixture of cis
and trans isomers (0.62 g, 93%) m.p. 119.degree.-121.degree. C.
Oxalate salt: .sup.1 H Nmr (major isomer, d.sub.6 DMSO) .delta.:
1.65-2.25 (6H, m), 3.09-3.57 (6H, m), 3.86 (3H, s), 5.04 (1H,
s)
.sup.13 C Nmr (major isomer, d.sub.6 -DMSO) 16.77, 31.04, 32.50,
46.86, 49.47, 51.33, 58.51, 62.34, 72.71, 93.45, 141.98
MS Calculated mass for C.sub.1 H.sub.6 N.sub.2 O=192.1263
Observed mass=192.1263
EXAMPLE 5
(.+-.) 1-Azabicyclo[3.2.1]oct-5-yl-N-methoxycarboximidoyl
chloride oxalate salt (E5) ##STR49##
Triphenylphosphine (2.20 g, 0.0084 mole) was added in a single
portion to 1-azabicyclo[3.2.1]oct-5-yl-N-methoxycarboxamide (D8,
1.54 g, 0.0084 mole) and carbon tetrachloride (2 ml) in
acetonitrile (50 ml) at reflux. After 2 minutes the reaction
mixture was poured into saturated aqueous potassium carbonate
solution (30 ml) and extracted with chloroform (4.times.50 ml). The
combined extracts were dried (Na.sub.2 SO.sub.4) and evaporated to
give an oil which was chromatographed on silica using 10%
methanol/chloroform as eluant to give the imidoyl chloride as a
crystallising oil (0.84 g, 50%). A portion of this material was
converted to the oxalate salt and recrystallised from
methanol/acetone to give the title compound (E5) as colourless
flakes m.p. 130.degree.-132.degree. C.
Oxalate: .sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.72-2.29 (6H, m),
3.16-3.56 (6H, m), 3.90 (3H, s).
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 16.68, 31.09, 32.44, 49.20,
49.34, 51.32, 58.58, 62.63, 139.74
Analysis: C.sub.9 H.sub.15 N.sub.2 OCl.C.sub.2 H.sub.2 O.sub.4
requires C: 45.14; H: 5.85; N: 9.57; found C: 44.98; H: 5.76; N:
9.45
EXAMPLE 6
(.+-.)
.alpha.-(Methoxyimino)-.alpha.-(1-azabicyclo[3.2.1]oct-5-yl)
acetonitrile hydrochloride salt (E6) ##STR50##
(.+-.) 1-Azabicyclo[3.2.1]oct-5-yl-N-methoxycarboximidoyl chloride
(E5, 0.65 g, 0.0032 mole) was treated with sodium cyanide (0.23 g,
0.0047 mole) as in the method of Example 3 to give the cyano-oxime
as an oil (0.41 g, 66%). A portion of this material was converted
to the hydrochloride salt and recrystsllised from acetone/ether to
give the title compound (E6) as a white crystalline solid m.p.
196.degree.-198.degree. C.
Hydrochloride: .sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.76-2.33 (6H,
m), 3.18-3.28 (2H, m), 3.33-3.56 (4H, m), 4.05 (3H, s).
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 16.51, 30.37, 31.92, 45.70,
49.31, 50.94, 57.84, 64.06, 109.01, 133.57.
Analysis: C.sub.10 H.sub.15 N.sub.3 O.HCl requires C: 52.29; H:
7.02; N: 18.29; found C: 52.10; H: 7.05; N: 18.04.
EXAMPLE 7
(.+-.) 1-Azabicyclo[3.2. ]oct-5-yl-N-methoxycarboximidonyl
bromide oxalate salt (E7) ##STR51##
Triphenylphosphine (0.86 g, 0.0033 mole) was added to a mixture of
1-azabicyclo[3.2.1]oct-5-yl-N-methoxycarboxamide (D8, 0.6 g, 0.0033
mole) and carbon tetrabromide (1.09 g, 0.0033 mole) in acetonitrile
(30 ml) at reflux. The reaction mixture was refluxed for 4 h then
poured into saturated potassium carbonate (30 ml) and extracted
with chloroform (5.times.50 ml). The combined extracts were dried
(Na.sub.2 SO.sub.4) and evaporated to give an oil which was
chromatographed on silica using 12% methanol/chloroform as eluant
to afford the imidoyl bromide as an oil. This material was
converted to the oxalate salt and recrystallised from acetone/ether
to give the title compound (E7) as a white crystalline solid (0.15
g, 14%) m.p. 145.degree.-147.degree. C.
Oxalate salt: .sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.72-2.26 (6H,
m), 3.15-3.55 (6H, m), 3.93 (3H, s).
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 16.74, 31.82, 33.14, 49.10,
50.39, 51.33, 58.94, 62.55, 133.70.
Analysis: C.sub.9 H.sub.15 N.sub.2 OBr.Chdb 2H.sub.2 O.sub.4
requires C: 39.19; H: 5.08; N: 8.31; found C: 39.14; H: 5.13; N:
8.09
EXAMPLE 8
(.+-.)
exo-1-Azabicyclo[2.2.1]hept-3-yl-N-methoxycarboximidoyl chloride
oxalate salt (E8) ##STR52##
exo-1-Azabicyclo[2.2.1]hept-3-yl-N-methoxycarboxamide (D10, 0.4 g,
0.0024 mole) was treated with triphenylphosphine (0.62 g, 0.0024
mole) and carbon tetrachloride (1 ml) in acetonitrile (30 ml) as in
the method of Example 5 to give the imidoyl chloride as a
colourless oil (0.15 g, 34%). A portion of this material was
converted to the oxalate salt and recrystallised from
acetone/methanol to yield the title compound (E8) as a white
crystalline solid m.p. 118.degree.-120.degree. C.
Oxalate salt: .sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.68 (1H, m),
1.98 (1H, m), 3.02-3.53 (8H, m), 3.91 (3H, s).
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 26.73, 38.58, 39.81, 46.91,
51.43, 54.78, 56.54, 62.69, 137.73.
Analysis: C.sub.8 H.sub.13 N.sub.2 OCl.C.sub.2 H.sub.2 O.sub.4
requires C: 43.10; H: 5.43; N: 10.05; found C: 42.98; H: 5.50; N:
9.74.
EXAMPLE 9
(.+-.)
exo-.alpha.-(Methoxyimino)-.alpha.-(1-azabicyclo[2.2.1]hept-3-yl)acetonitr
ile hydrochloride salt (E9) ##STR53##
(.+-.)1-Azabicyclo[2.2.1]hept-3-yl-N-methoxycarboximidoyl chloride
(E8, 0.14 g, 0.0007 mole) was treated with sodium cyanide (0.06 g,
0.0012 mole) as in the method of Example 3 to give the cyano-oxime
as a pale yellow oil (0.09 g, 68%). A portion of this material was
converted to the hydrochloride salt and recrystallised from
methanol/acetone to give the title compound (E9) as a white
crystalline solid m.p. 213.degree.-215.degree. C.
Hydrochloride: .sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.76 (1H,m),
2.04 (1H, m), 3.03-3.38 (5H, m), 3.52 (2H, m), 4.04 (3H, s).
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 26.72, 39.67, 42.05, 51.50,
53.97, 56.55, 64.25, 110.44, 131.86
Analysis C.sub.9 H.sub.13 N.sub.3 O.HCl requires C: 50.12; H: 6.54;
N: 19.48; found C: 49.82; H: 6.60; N: 19.16.
EXAMPLE 10
(.+-.)
1-Azabicyclo[2.2.2]oct-3-yl-N-methoxycarboximidoyl
fluoride oxalate salt (E10) ##STR54##
A mixture of 1-azabicyclo[2.2.2]oct-3-yl-N-methoxycarboximidoyl
chloride (E1, 0.1 g, 0.0005 mole) and cesium fluoride supported on
calcium fluoride (5 g prepared by slowly evaporating to dryness a
slurry of calcium fluoride in a solution of cesium flouride in
methanol for 1 h at 80.degree. C. under reduced pressure in a mole
ratio of 5:1)* in DMF (15 ml) were neared at 145.degree. C. for 5
days. The reaction mixture was filtered, concentrated in vacuo, and
partitioned between saturated potassium carbonate and chloroform
(4.times.50 ml). The combined organic extracts were dried (Na.sub.2
SO.sub.4) and evaporated to give an oil which was chromatographed
on silica gel using 10% methanol/chloroform as eluant to yield the
imidoyl fluoride as an oil. Conversion to the oxalate salt afforded
the title compound (E10) as a white crystalline solid (0.042 g,
31%)m.p. 102.degree.-108.degree. C.
Oxalate: .sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.70-1.97 (5H, m),
3.10-3.37 (6H, m), 3.46 (1H, m), 3.79 (3H, s).
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 18.57, 21.99, 22.28, 33.62
(d, .sup.2 J.sub.CF =28Hz), 45.08, 45.34, 46.09, 62.60, 151.40 (d,
.sup.1 J.sub.CF =329Hz).
M.S. Calculated mass for C.sub.9 H.sub.15 N.sub.2 OF=186.1168
Observed mass=186.1162
EXAMPLE 11
1-Azabicyclo[2.2.1]hept-4-yl-N-methoxycarboximidoyl chloride
oxalate salt (E11) ##STR55##
1-Azabicyclo[2.2.1]hept-4-yl-N-methoxycarboxamide (D18, 2 g, 0.0118
mole) was treated with triphenylphosphine (3.09, 0.0118 mole) and
carbon tetrachloride (4 ml) in acetonitrile (100 ml) as in the
method of Example 5 to give the imidoyl chloride as a low-melting
solid (1.70 g, 77%). A portion of this material was converted to
the oxalate salt and recrystallised from methanol/acetone to give
the title compound (E11) as a white crystalline solid m.p.
128.degree.-130.degree. C.
Oxalate salt: .sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.96 (2H, m),
2.20 (2H, m), 3.22-3.34 (4H, m), 3.45 (2H, m), 3.92 (3H, s).
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 31.59 (2C), 52.24 (2C),
52.73, 59.92, 62.72, 136.54.
Analysis C.sub.8 H.sub.13 N.sub.2 OCl.C.sub.2 H.sub.2 O.sub.4
requires C: 43.10; H: 5.43; N: 10.05; found C: 43.06; H: 5.47; N:
10.04.
EXAMPLE 12
.alpha.-(Methoxyimino)-.alpha.-(1
-azabicyclo[2.2.1]hept-4-syl)acetonitrile hydrochloride salt (E12)
##STR56##
1 -Azabicyclo[2.2.1 ]hept-4-yl-N-methoxycarboximidoyl chloride
oxalate salt (E11, 0.4 g, 0.0021 mole) was treated with sodium
cyanide (0.16 g, 0.0033 mole) as in the method of Example 3 to give
the imidoyl cyanide as a crystallising oil. Conversion to the
hydrochloride salt afforded the title compound (E12) as a white
crystalline solid (0.20 g, 44%) m.p. 186.degree.-187.degree. C.
Hydrochloride: .sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.99 (2H, m)
2.24 (2H, m), 3.32-3.44 (4H, m), 3.53 (2H, m), 4.09 (3H, s).
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 30.66 (2C), 48.94, 51.89
(2C), 59.33, 64.16, 109.00, 130.10.
M.S. Calculated mass for C.sub.9 H.sub.13 N.sub.3 O=179.1059
Observed mass=179.1057
EXAMPLE 13
1-Azabicyclo[2.2.1]hept-4-yl-N-methoxycarboximidoyl bromide oxalate
salt (E13) ##STR57##
1-Azabicyclo[2.2.1]hept-4-yl-N-methoxycarboxamide (D18, 0.7 g,
0.0041 mole) was converted to the hydrobromide salt and treated
with triphenylphosphine (1.08 g, 0.004 mole) and carbon
tetrabromide (1.37 g, 0.0041 mole) in acetonitrile (50 ml) at
reflux for 1 h. The reaction mixture was poured into saturated
potassium carbonate (30 ml) and extracted with chloroform
(5.times.50 ml). The combined organic extracts were dried (Na.sub.2
SO.sub.4) and evaporated to an oil which was chromatographed on
silica using 2-3% methanol/chloroform as eluant to afford the
imidoyl bromide as an oil (0.49 g, 51%). A portion of this material
was converted to the oxalate salt and recrystallised from
acetone/ether to give the title compound (E13) as colourless flakes
m.p. 133.degree.-134.degree. C.
Oxalate salt: .sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.96 (2H, m),
2.18 (2H, m), 3.22-3.36 (4H, m), 3.46 (2H, m), 3.94 (3H, s).
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 32.14 (2C), 52.17 (2C),
54.07, 60.35, 62.61, 129.66.
Analysis C.sub.8 H.sub.13 N.sub.2 OBr.C.sub.2 H.sub.2 O.sub.4
requires C: 37.17; H: 4.68; N: 8.67; found C: 37.38; H: 4.67; N:
8.83
EXAMPLE 14
1-Azabicyclo[2.2.1]hept-4-yl-N-methoxycarboximidoyl fluoride
oxalate salt (E14) ##STR58##
1-Azabicyclo[2.2.1]hept-4-yl-N-methoxycarboxamide (D18, 1.6 g,
0.0094 mole) was converted to the hydrofluoride salt by the
addition of hydrogen fluoride-pyridine (Aldrich). The salt was
dissolved in refluxing acetonitrile (150 ml) and
diethylaminosulphur trifluoride (DAST) (1.25 ml, 0.0095 mole) in
acetonitrile (5 ml) was added in a single portion. The reaction
mixture was immediately cooled and poured into saturated potassium
carbonate (100 ml) and extracted with chloroform (4.times.100 ml).
The combined organic extracts were dried (Na.sub.2 SO.sub.4) and
evaporated to an oil which was chromatographed on silica using 2-3%
methanol/chloroform as eluant to yield the imidoyl fluoride as an
oil (0.40 g, 25%). Addition of oxalic acid and recrystallisation
from methanol/acetone gave the title compound (E14) as a white
crystalline solid m.p. 114.degree.-116.degree. C.
Oxalate salt: .sup.1 H Nmr (d.sub.6 DMSO) .delta.: 1.89 (2H, m),
2.17 (2H, m), 3.16-3.29 (4H, m), 3.42 (2H, m), 3.77 (3H, s)
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 29.86 (2C), 46.78 (d, .sup.2
J.sub.CF =29Hz), 52.08 (2C), 59.22, 62.66, 150.60 (d, .sup.1
J.sub.CF= 330Hz)
Analysis C.sub.8 H.sub.13 N.sub.2 OF.C.sub.2 H.sub.2 O.sub.4
requires C: 45.80; H: 5.77; N: 10.68; found C: 45.79; H: 5.78; N:
10.72
EXAMPLE 15
(.+-.) 1-Azabicyclo[2.2.2]oct-3-yl cyclopropyl ketone
trans-O-methyloxime hydrochloride salt (E15) ##STR59##
(.+-.) 1-Azabicyclo[2.2.2]oct-1-yl cyclopropyl ketone (D19, 0.1 g,
0.0006 mole) in methanol (15 ml) was treated with methoxylamine
hydrochloride (0.15 g, 0.0018 mole) at reflux for 20 h. After
cooling, the reaction mixture was concentrated in vacuo, saturated
potassium carbonate (20 ml) was added and the mixture was extracted
with chloroform (4.times.30 ml). The combined organic extracts were
dried (Na.sub.2 SO.sub.4) and evaporated to give an oil which was
chromatographed on silica gel using 15-20% methanol/chloroform as
eluant to afford the oxime as an oil (0.062 g, 53%). This was
converted to the hydrochloride salt and recrystallised from
methanol/acetone to give the title compound (E15) as a white
crystalline solid m.p. 225.degree.-228.degree. C. (decomp.).
Hydrochloride: .sup.1 H Nmr (d.sub.6 DMSO) .delta.: 0.66-0.89 (4H,
m), 1.66 (1H, m), 1.80-2.06 (5H, m), 2.45 (1H, m), 3.03-3.25 (6H,
m), 3.82 (3H, s).
.sup.13 C Nmr (d.sub.6 DMSO) .delta.: 4.61, 5.16, 8.80, 17.89,
22.85, 23.52, 32.58, 44.95, 45.28, 47.34, 61.43, 157.66
M.S. Calculated mass for C.sub.12 H.sub.20 N.sub.2 O=208.1576
Observed mass=208.1576
EXAMPLE 16
(.+-.) endo-1-Azabicyclo[2.2.1]hept-3-yl -N-methoxycarboximidoyl
chloride oxalate salt (E16) ##STR60##
(.+-.) endo-1-Azabicyclo[2.2.1]hept-3-yl-N-methoxycarboxamide (D23)
(1.42 g, 0.0083 mole) was treated with triphenylphosphine (2.19 g,
0.0083 mole) and carbon tetrachloride (2 ml) in acetonitrile (50
ml) as in the method of Example 5 to give the imidoyl chloride as a
colourless oil (0.6 g, 38%). A portion of this material was
converted to the oxalate salt and crystallised from ethanol/diethyl
ether to yield the title compound (E16) as a white crystalline
solid m.p. 123.degree.-125.degree. C.
Oxalate salt: .sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.55-1.68 (1H,
m), 1.95-2.05 (1H, m), 3.10-3.70 (8H, m), 4.01 (3H, s).
.sup.13 C NMR (d.sub.6 DMSO) .delta.: 22.13, 39.27, 45.61, 51.91,
52.59, 58.47, 62.78, 136.78
Analysis: C.sub.8 H.sub.13 N.sub.2 OCl.C.sub.2 H.sub.2 O.sub.4
requires C: 43.10; H: 5.43; N: 10.05; found C: 42.99; H: 5.47; N:
9.86
EXAMPLE 17
(.+-.)
endo-.alpha.-(Methoxyimino)-.alpha.-(1-azabicyclo[2.2.1]hept-3-yl)acetonit
rile oxalate salt (E17) ##STR61##
(.+-.) endo-1-Azabicyclo[2.2.1]hept-3-yl-N-methoxycarboximidoyl
chloride (E16) (0.5 g, 0.0027 mole) was treated with sodium cyanide
(0.2 g, 0.004 mole) as in the method of Example 3 to give the
cyano-oxime as an oil (0.035 g, 7%). This material was converted to
the oxalate salt and crystallised from ethanol/diethyl ether to
give the title compound (E17) as a white crystalline solid m.p.
125.degree.-130.degree. C.
Oxalate salt: .sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.59-1.72 (1H,
m), 1.97-2.11 (1H, m), 3.11-3.73 (8H, m), 4.17 (3H, s)
.sup.13 C NMR (d.sub.6 DMSO) .delta.: 22.05, 39.06, 40.88, 52.03,
52.18, 58.93, 64.05, 110.10, 130.36
M.S. Calculated mass for C.sub.9 H.sub.13 N.sub.3 O=179.1058
Observed mass=179.1062
EXAMPLES 18 AND 19
(.+-.) exo- and
endo-1-Azabicyclo[2.2.1]hept-3-yl-N-methoxycarboximidoyl bromide
oxalate salts (E18) and (E19) ##STR62##
A 7:2 mixture of (.+-.) exo- and
endo-1-azabicyclo[2.2.1]hept-3-yl-N-methoxycarboxamide (D10) and
(D23) (1.5 g, 0.0088 mole) was converted to the hydrobromide salts
by addition of one equivalent of HBr in acetone. The mixture was
evaporated to dryness and the residue dissolved in refluxing
acetonitrile (50 ml). Carbon tetrabromide (2.9 g, 0.0088 mole) was
added followed by triphenylphosphine (2.3 g, 0.0088 mole). The
mixture was heated under reflux for 30 min. A further amount of
carbon tetrabromide (1.0 g, 0.003 mole) and triphenylphosphine (0.8
g, 0.003 mole) was added to drive the reaction to completion
followed by a further 30 min at reflux. The mixture was allowed to
cool slightly and saturated potassium carbonate solution (50 ml)
was added with vigorous stirring. The mixture was extracted with
chloroform (3.times.100 ml) and the combined organic extracts were
washed with 2N hydrochloric acid (2.times.100 ml). The combined
acid extracts were then saturated by careful addition of potassium
carbonate. The oil which separated was extracted into chloroform
(2.times.100 ml) which was dried (Na.sub.2 SO.sub.4), filtered and
evaporated to dryness.
The residue was chromatographed on silica gel eluting with 0-5%
methanol/chloroform. This gave the exo compound as the less polar
fraction (0.37 g, 18%) which was converted to the oxalate salt.
Trituration with diethyl ether gave the title compound (E18) (0.47
g) as a white crystalline solid m.p. 98.degree.-102.degree. C.
The more polar fraction gave the endo isomer (0.07 g, 4%) which was
converted to the oxalate salt. Crystallisation from ethanol/diethyl
ether gave the title compound (E19) (0.068 g) as a white
crystalline solid m.p. 144.degree.-148.degree. C.
(E18) Oxalate salt
.sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.72-1.83 (1H, m), 2.01-2.15
(1H, m), 3.12-3.62 (8, m), 4.02 (3H, s).
.sup.13 C NMR (d.sub.6 DMSO) .delta.: 26.94, 40.39, 49.45, 51.70,
55.56, 56.70, 62.92, 131.27
Analysis: C.sub.8 H.sub.13 N.sub.2 OBr.C.sub.2 H.sub.2 O.sub.4
requires C: 37.17; H: 4.68; N: 8.67; found C: 37.14; H: 4.64; N:
8.66
(E19) Oxalate salt
.sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.55-1.70 (1H, m), 1.91-2.07
(1H, m), 3.09-3.73 (8H, m), 4.04 (3H, s)
.sup.13 C NMR (d.sub.6 DMSO) .delta.: 22.03, 40.12, 47.64, 51.91,
52.96, 58.20, 62.68, 129.87
Analysis: C.sub.8 H.sub.13 N.sub.2 OBr.C.sub.2 H.sub.2 O.sub.4
requires C: 37.17; H: 4.68; N: 8.67; found C: 37.31; H: 4.67; N:
8.60
EXAMPLE 20
(.+-.) exo-1-Azabicyclo[2.2.1]hept-3-yl-N-methoxy carboximidoyl
fluoride oxalate salt (E20) ##STR63##
(.+-.) exo-1-Azabicyclo[2.2.1]hept-3-yl-N-methoxycarboximidoyl
bromide (E18) (0.14 g, 0.0006 mole) in dry dimethylformamide (10ml)
was heated at 140.degree. C. for 20 h with cesium fluoride
supported on calcium fluoride (6.0 g)*. The mixture was allowed to
cool and then filtered washing the filter cake with
dimethylformamide (10 ml). The filtrate was evaporated to dryness
and the residue chromatographed on silica eluting with 0-5%
methanol/chloroform. This gave the fluoro compound as an oil (0.025
g, 24%). This material was converted to the oxalate and
crystallised from ethanol/diethyl ether to yield the title compound
(E20) as a white crystalline solid m.p. 115.degree.-117.degree.
C.
Oxalate salt .sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.59-1.83 (1H,
m), 1.88-2.03 (1H, m), 2.95-3.41 (8H, m), 3.77 (3H, s).
M.S. Calculated mass for C.sub.8 H.sub.12 N.sub.2 OF=172.1012
Observed mass=172.1012
EXAMPLE 21
(.+-.) exo-1-Azabicyclo[2.2.1]hept-3-yl-N-ethoxy carboximidoyl
chloride oxalate salt (E21) ##STR64##
(.+-.) exo-1-Azabicyclo[2.2.1]hept-3-yl-N-ethoxycarboxamide (D24)
(0.5 g, 0.0027 mole) was treated with triphenylphosphine (0.72 g,
0.0027 mole) and carbon tetrachloride (1 ml) in acetonitrile (20
ml) as in the method of Example 5 to give the imidoyl chloride as a
colourless oil (0.15 g, 27%). This material was converted to the
oxalate and crystallised from ethanol/diethyl ether to give the
title compound (E21) as a white crystalline solid m.p.
126.degree.-128.degree. C.
Oxalate salt .sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.34 (3H, t,
J=7Hz)), 1.70-1.83 (1H, m), 2.00-2.15 (1H, m), 3.11-3.64 (8H, m),
4.27 (2H, q, J=7Hz).
.sup.13 C NMR (d.sub.6 DMSO) .delta.: 14.27, 26.68, 39.65, 47.03,
51.40, 54.77, 56.51, 70.41, 137.31
Analysis: C.sub.9 H.sub.15 N.sub.2 OCl.C.sub.2 H.sub.2 O.sub.4
requires C: 45.14; H: 5.85; N: 9.57: found C: 44.90: H: 5.80: N:
9.34
EXAMPLE 22
(.+-.) exo-.alpha.-(Ethoxyimino)-.alpha.-(1-azabicyclo[2.2.
1]hept-3-yl)acetonitrile oxalate salt (E22) ##STR65##
(.+-.) exo-1-Azabicyclo[2.2.1]hept-3-yl-N-ethoxycarboximidoyl
chloride (E21) (0.415 g, 0.002 mole) was treated with sodium
cyanide (0.16 g, 0.003 mole) as in the method of Example 3 to give
the cyano-oxime as an oil (0.2 g, 51%). This material was converted
to the oxalate salt sad crystallised from acetone/diethyl ether to
give the title compound (E22) as a white crystalline solid m.p.
110.degree.-112.degree. C.
Oxalate salt .sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.37 (3H, t,
J=7Hz), 1.72-1.85 (1H, m), 2.01-2.15 (1H, m), 3.05-3.65 (8H, m),
4.40 (2H, q, J=7Hz).
.sup.13 C NMR (d.sub.6 DMSO) .delta.: 14.19, 26.83, 39.62, 42.14,
51.46, 54.23, 56.39, 71.92, 110.32, 131.58
Analysis: C.sub.10 H.sub.15 N.sub.3 O.C.sub.2 H.sub.2 O.sub.4
requires C: 50.88; H: 6.05; N: 14.83; found C: 50.70; H: 6.04; N:
14.61
EXAMPLE 23
(.+-.) exo-1-Azabicyclo[2.2.1]hept-3-yl-N-ethoxy carboximidoyl
bromide oxalate salt (E23) ##STR66##
(.+-.) 1-Azabicyclo[2.2.1]hept-3-yl-N-ethoxycarboxamide (D24) (2.72
g, 0.0147 mole) was converted to the hydrobromide salt and treated
with carbon tetrabromide (6.3 g, 0.19 mole) and triphenylphosphine
(5.0 g, 0.019 mole) as in the method of Example 13 to give the
imidoyl bromide as an oil (0.338 g, 9%). A portion of this material
was converted to the oxalate salt and crystallised from
ethanol/diethyl ether to give the title compound (E23) as a white
crystalline solid m.p. 138.degree.-140.degree. C.
Oxalate salt: .sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.33 (3H, t,
J=7Hz), 1.71-1.85 (1H, m), 2.00-2.17 (1H, m), 3.12-3.61 (8H, m),
4.30 (2H, q, J=7Hz)
.sup.13 C NMR (d.sub.6 DMSO) .delta.: 14.33, 26.64, 40.12, 49.32,
51.48, 55.41, 56.47, 70.35, 130.56
M.S. calculated mass for C.sub.9 H.sub.15 N.sub.2 O.sup.79
Br=246.0366
Observed mass=246.0363
Calculated mass for C.sub.9 H.sub.15 N.sub.2 O.sup.81
Br=248.0345
Observed mass=248.0348
EXAMPLES 24 AND 25
(.+-.) exo- and
endo-1-Azabicyclo[2.2.1]hept-3-yl-N-prop-2-ynyloxycarboximidoyl
chloride oxalate salts (E24) and (E25) ##STR67##
(.+-.) exo- and
endo-1-Azabicyolo[2.2.1]hept-3-yl-N-prop-2-ynloxycarboxamide (D25)
(1.0 g, 0.0051 mole) was treated with triphenylphospine (1.35 g,
0.0051 mole) and carbon tetrachloride (2.0 ml) in acetonitrile as
in the method of Example 5. This gave the imidoyl chlorides which
were separated by chromatography on silica eluting with 0-5%
methanol/chloroform. This gave the exo compound as the less polar
fraction (0.108 g, 10%) which was converted to the oxalate salt.
Crystallisation from ethanol/diethyl ether gave the title compound
(E24) (0.12 g) m.p. 103.degree.-105.degree. C.
The more polar fraction gave the endo isomer (0.046 g, 4%) which
was converted to the oxalate salt. Crystallisation from
ethanol/diethyl ether gave the title compound (E25) (0.055 g) m.p.
150.degree.-156.degree. C.
(E24) Oxalate salt
.sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.71-1.86 (1H, m), 2.01-2.15
(1H, m), 3.09-3.61 (8H, m), 3.69-3.74 (1H, m), 4.90 (2H, s).
.sup.13 C NMR (d.sub.6 DMSO) .delta.: 26.68, 39.73, 47.09, 51.46,
54.80, 56.50, 62.40, 78.71, 79.12, 139.46
Analysis: C.sub.10 H.sub.13 N.sub.2 OCl.C.sub.2 H.sub.2 O.sub.4
requires C: 47.61; H: 4.99; N: 9.25; found C: 47.63; H: 5.00; N:
9.05
(E25) Oxalate Salt
.sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.57-1.70 (1H, m), 1.95-2.04
(1H, m), 3.04-3.68 (8H, m), 3.68-3.72 (1H, m), 4.92 (2H, s).
.sup.13 C NMR (d.sub.6 DMSO) .delta.: 22.22, 39.31, 45.80, 51.86,
52.76, 58.54, 62.45, 78.62, 79.20, 138.61
Analysis: C.sub.10 H.sub.13 N.sub.2 OCl.C.sub.2 H.sub.2 O.sub.4
requires C: 47.61; H: 4.99; N: 9.25; found C: 47.26; H: 4.92; N:
8.95
EXAMPLE 26
(.+-.) exo-1-Azabicyclo[2.2.1]hept-3-yl cyclopropyl ketone
O-methyloxime oxalate salt (E26) ##STR68##
A solution of (.+-.) endo-1-azabicyclo[2.2.1]hept-3-yl cyclopropyl
ketone (D26) (0.13 g, 1.6 mmole) in dry methanol (7 ml), under
nitrogen, was treated with methoxylamine hydrochloride (0.13 g, 3.2
mmole) then tefluxed for 41 h. Additions of further methoxylamine
hydrochloride (0.39 g, 9.6 mmole) and pyridine (0.186 g, 4.8 mmole)
were made during this period. The reaction was concentrated in
vacuo, treated with saturated aqueous potassium carbonate (10 ml)
then extracted with chloroform (4.times.30 ml). The combined
organic extracts were dried (Na.sub.2 SO.sub.4), concentrated in
vacuo and the residue chromatographed on silica eluting with 10%
methanol in chloroform to afford the oxime ether as a clear gum (19
mg, 25%). This was converted to the oxalate salt which was
recrystallised from methanol/ether to give the title compound (E26)
as a white solid m.p. 124.degree. C. (decomp).
.sup.1 H NMR (CDCl.sub.3) (free base) .delta.: 0.58-0.75 (2H, m),
0.79-0.95 (2H, m), 1.19-1.32 (2H, m), 1.63-1.82 (2H, m), 2.41-2.50
(1H, m), 2.58-2.77 (4H, m), 2.95-3.15 (2H, m), 3.86 (3H, s).
M.S. Calculated mass for C.sub.11 H.sub.18 N.sub.2 O=194.1419
Observed mass=194.1428
EXAMPLE 27 AND 28
(.+-.) exo- and
endo-3-Oxo-3-(1-azabicyclo[2.2.1]hept-3-yl)propionitrile-O-methyl
oxime oxalate salts (E27) and (E28) ##STR69##
A solution of (.+-.) exo- and
endo-3-oxo-3-(1-azabicy-clo[2.2.1]hept-3-yl)propionitrile lithium
salt (D27) (1.5 g, approximately 2.95 mmoles) in dry methanol (15
ml), under nitrogen, was cooled to 0.degree. C. then treated with
methoxylamine hydrochloride (0.49 g, 5.9 mmole) and acetic acid
(0.18 g, 0.295 mmole). The reaction was allowed to warm to room
temperature over 17 h then heated at reflux for 1 h. The reaction
mixture was concentrated in vacuo, treated with saturated aqueous
potassium carbonate (20 ml) then extracted with chloroform (20
ml.times.4). The combined organic extracts were dried (Na.sub.2
SO.sub.4) then concentrated in vacuo and the residue
chromatographed on silica in a gradient of 0-5% methanol in
chloroform. This afforded the exo-oxime (85 mg, 15%) and endo-oxime
(19 mg, 3%) as gums.
The endo-isomer was converted to the oxalate salt and
recrystallised from methanol/ether to give the title compound (E28)
as a white solid m.p. 127.degree. C. (decomp).
The exo-isomer was converted to the oxalate salt and recrystallised
from acetone/ether to give the title compound (E27) as a
hygroscopic solid.
(E28) Free base
.sup.1 H NMR (CDCl.sub.3) .delta.: 1.26-1.38 (1H, m), 1.47-1.63
(1H, m), 2.55-2.70 (2H, m), 2.76-3.18 (6H, m), 3.35 (2H, ABq), 3.87
(3H, s).
M.S. Calculated mass for C.sub.10 H.sub.15 N.sub.3 O=193.1215
Observed mass=193.1212
(E27) Oxalate salt
.sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.5-1.76 (1H, m), 1.94-2.12
(1H, m), 2.87-3.42 (8H, m), 3.74 (2H, ABq), 3.87 (3H, s)
.sup.13 C NMR (d.sub.6 DMSO) .delta.: 17.65, 26.92, 38.88, 43.96,
51.47, 53.31, 55.88; 62.14, 110.62, 148.24
M.S. Calculated mass for C.sub.10 H.sub.15 N.sub.3 O=192.1215
Observed mass=193.1215
EXAMPLES 29 AND 30
(-) .alpha.-(Methoxyimino)-.alpha.-(1
-azabicyclo[2.2.2]oct-3-yl)-acetonitrile oxalate salt (E29) and
(+)
.alpha.-(methoxyimino)-.alpha.-(1-azabicyclo[2.2.2]oct-3-yl)acetonitrile
oxalate salt (E30) ##STR70##
A solution of (.+-.)
.alpha.-(methoxyimino)-.alpha.-(1-azabicyclo[2.2.2]oct-3-yl)acetonitrile
(E3) (0.3 g, 1.55 mmol) in methanol (10 ml) was treated with
(S)-(+)-1,1'-binapht- hyl-2,2'-diyl hydrogen phosphate (0.38 g,
1.09 mmol) and the resulting solution concentrated in vacuo to
leave a colourless oil. This material was dissolved in hot acetone
(15 ml), diluted with ether (5 ml) and left to stand at room
temperature for 24 h. The white crystalline solid was filtered off
(372 mg) and recrystallised a further three times from
methanol/acetone to give 260 mg of white solid. This material was
treated with saturated potassium carbonate (50 ml) and extracted
with chloroform (3.times.50 ml). The combined extracts were dried
(Na.sub.2 SO.sub.4) and concentrated in vacuo to give a colourless
oil (90 mg), which was converted to its oxalate salt and
recrystallised from methanol/acetone to give the title compound
(E29) as a white solid m.p. 151.degree.-153.degree. C.
Oxalate salt: [.alpha.].sup.20.sub.D =-13.4.degree. (C=0.932% in
ethanol).
The purity of the enantiomer was confmned as >95% by chiral HPLC
[2.times.(chiral - AGP, 100.times.4.0 mm) coupled in series to make
a total column length of 200 mm using 0.02M of phosphate (pH 7.0)
as eluant].
The mother liquors from the above recrystallisations were combined,
concentrated in vacuo and the residue partitioned between saturated
potassium carbonate (50 ml) and chloroform (3.times.50 ml). The
combined extracts were dried (Na.sub.2 SO.sub.4) and concentrated
in vacuo to leave a colourless oil (188 mg), which was dissolved in
methanol (10 ml) and treated with (R)-(-)-1,1'-binaphthyl-2,2'-
diyl hydrogen phosphate (0.27 g, 0.78 mmol). The resulting solution
was concentrated in vacuo to give a colourless oil which was
taken-up in hot acetone (15 ml), treated with ether (5 ml) and left
to stand at room temperature for 24 h. The white crystalline solid
was filtered off (416 mg) and recrystallised twice from
methanol/acetone to give 297 mg of a white solid. This material was
treated with saturated potassium carbonate (50 ml) and extracted
with chloroform (3.times.50 ml). The combined organic extracts were
dried (Na.sub.2 SO.sub.4) and concentrated in vacuo to give a
colourless oil (94 mg), which was converted to the oxalate salt and
recrystallised from methanol/acetone to give the title compound
(E30) as a white solid m.p. 154.degree.-156.degree. C.
Oxalate salt: [.alpha.].sup.20.sub.D =-14.4.degree. (C=0.424% in
ethanol)
EXAMPLE 31
(.+-.)
1-Azabicyclo[3.2.1]oct-5-yl-N-methoxycarboximidoyl fluoride oxalate
salt (E31) ##STR71##
Pyridine (3 ml, 0.037 mole) was added to a solution of (.+-.)
1-azabicyclo[3 2.1]oct-5-yl-N-methoxycarboxamide (D8, 5.4 g, 0.029
mole) in acetone (100 ml). The solution was then made just acidic
by the addition of hydrogen fluoride-pyridine (Aldrich) and
evaporated in vacuo. The resultant gum was co-evaporated with
toluene, dried under vacuum and then taken-up in refluxing dry
acetonitrile (300 ml). Diethylaminosulphur trifluoride (DAST) (4.26
ml, 0.032 mole) in acetonitrile (20 ml) was added in a single
portion and the reaction mixture was immediately cooled and poured
into saturated potassium carbonate (150 ml). The mixture was
extracted with chloroform (3.times.200 ml) and the combined
extracts were dried (Na.sub.2 SO.sub.4) and evaporated to an oil.
Chromatography on silica using 4% methanol/chloroform as eluant
afforded the imidoyl fluoride as a yellow oil (1.62 g, 31%).
Addition of oxalic acid and recrystallisation from methanol/acetone
gave the title compound (E31) as a white crystalline solid m.p.
104.degree.-107.degree. C.
Oxalate salt: .sup.1 H NMR (d.sub.6 DMSO) .delta.: 1.70-2.30 (6H,
m), 3.10-3.55 (6H, m), 3.76 (3H, s).
.sup.13 C NMR (D.sub.6 DMSO) .delta.: 16.31, 29.78, 30.52, 43.82
(d, .sup.2 J.sub.CF =27Hz), 49.55, 51.33, 57.63, 62.50, 152.36 (d,
.sup.1 J.sub.CF =333Hz).
Analysis C.sub.9 H.sub.15 N.sub.2 OF.C.sub.2 H.sub.2 O.sub.4
requires C: 47.82; H: 6.2; N: 10.14; found C: 47.74; H: 6.15; N:
10.09
BIOLOGICAL ACTIVITY
Radio ligand Binding
Cerebral cortex from Hooded Lister rats (Olac, UK) is homogenised
in 2.5 vols ice-cold 50 mM tris buffer pH 7.7 (at 25.degree. C.).
After centrifugation at 25,000.times.g at 4.degree. C. for 15 min
the pellet is resuspended in 2.5 vols buffer and the wash repeated
3 times more. The final resuspension is in 2.5 volumes and the
homogenates are stored in 1 ml aliquots at -20.degree. C.
Incubations (total volume 2 ml) are prepared using the above buffer
with the addition of 2 mM magnesium chloride in the
3H-Oxotremorine-M (3H-OXO-M) experiments. For 3H-Quinuclidinyl
Benzilate (3H-QNB), 1 ml of stored membranes is diluted to 30 ml
and 0.1 ml mixed with test compound and 0.27 nM (c. 25,000 cpm)
3H-QNB (Amersham International). For 3H-OXO-M, 1 ml of membranes is
diluted to 6 ml and 0.1 ml mixed with test compound and 2 nM (c.
250,000 cpm) 3H-OXO-M (New England Nuclear).
Non-specific binding of 3H-QNB is defined using 1 .mu.M Atropine
sulphate (2 .mu.M Atropine) and of 3H-OXO-M using 10 .mu.M
Oxotremorine. Non-specific binding values typically are 5% and 25%
of total binding, respectively. Incubations are carried out at
37.degree. C. for 30 min and the samples filtered using Whatman
GF/B filters. (In the 3H-OXO-M experiments the filters are
presoaked for 30 min in 0.05% polyethylenimine in water). Filters
are washed with 3.times.4 ml ice-cold buffer. Radioactivity is
assessed using a Packard BPLD scintillation counter, 3 ml
Pico-Fluor 30 (Packard) as scintillant.
This test provides an indication of the muscarinic binding activity
of the test compound. The results are obtained as IC.sub.50 values
(i.e. the concentration which inhibits binding of the ligand by
50%) for the displacement of the muscarinic agonist 3H-OXO-M and
the muscarinic antagonist 3H-QNB. The ratio IC.sub.50
(3H-QNB)/IC.sub.50 (3H-OXO-M) gives an indication of the agonist
character of the compound. Agonists typically exhibit a large
ratio; antagonists typically exhibit a ratio near to unity. The
results are shown in Table 1.
TABLE 1 ______________________________________ [3H]-OXO-M [3H]-QNB
Compound IC.sub.50 (nM) IC.sub.50 (nM)
______________________________________ E1 93 897 E2 1000 8000 E3 29
493 E4 162 1458 E5 72 3816 E6 114 251 E7 190 2850 E8 64 3328 E9 25
2100 E10 34 2108 E11 38 9000 E12 21 1995 E13 170 10030 E14 48 15504
E15 386 22237 E16 99 7000 E17 16 3600 E18 46 11000 E19 127 3600 E20
11 3000 E21 570 15500 E22 233 10000 E24 112 2100 E27 71 1100 E28
750 16500 E29 180 1800 E30 20 340
______________________________________
* * * * *