United States Patent [19]
`Villhauer
`
`US006166063A
`[11] Patent Number:
`[45] Date of Patent:
`
`6,166,063
`Dec. 26, 2000
`
`[54] N-(SUBSTITUTED GLYCYL)-2
`CYANOPYRROLIDINES,
`PHARMACEUTICAL COMPOSITIONS
`CONTAINING THEM AND THEIR USE IN
`INHIBITING DIPEPTIDYL PEPTIDASE-IV
`
`Yamada, et al. Bulletin of the Chemical Society of Japan,
`vol. 50, No. 7, pp. 1827—1830 (1977).
`
`Yamada, et al. Bulletin of the Chemical Society of Japan,
`vol. 51, No. 3, pp. 878—883 (1978).
`
`[75] Inventor: Edwin Bernard Villhauer, Morristown,
`NJ.
`
`[73] Assignee: Novartis AG, Basel, Switzerland
`
`[21] Appl. No.: 09/458,224
`
`[22]
`
`Filed:
`
`Dec. 9, 1999
`
`DerWent Abstract 95: 302548. (1994).
`
`DerWent Abstract 84: 177689. (1983).
`
`DerWent Abstract 96: 116353. (1994).
`
`Kaspari, et al. Biochimica et Biophysica, vol. 1293, pp.
`147—153 (1996).
`
`AshWorth, et al. Bioorganic and Medicinal Chemistry Let
`ters, vol. 6, No. 10, pp. 1163—1166 (1996).
`
`Coutts, et al. J. Med Chem., vol. 39, pp. 2087—2094 (1996).
`
`Related US. Application Data
`
`Deacon, et al. Diabetes, vol. 44, pp. 1126—1131 (Sep. ’96).
`
`[63] Continuation of application No. 09/209,068, Dec. 10, 1998,
`abandoned.
`
`[51] Int. Cl.7 ......................... .. A61K 31/401; A61P 5/48;
`C07D 207/12; C07D 207/14
`[52] US. Cl. ........................ .. 514/423; 514/428; 548/528;
`548/530
`[58] Field of Search ................................... .. 514/423, 428;
`548/530, 528
`
`[56]
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`4,661,512
`
`4/1987 Laruelle et al. ...................... .. 514/423
`
`FOREIGN PATENT DOCUMENTS
`
`AshWorth, et al. Bioorganic and Medicinal Chemistry Let
`ters, vol. 6, No. 22, pp. 2745—2748 (1996).
`
`Augustyns, et al. Eur J. Med. Chem., vol. 32, pp. 301—309
`(1997).
`
`Hughes, et al. Biochemistry, vol. 38, pp. 11597—11603
`(1999).
`
`Primary Examiner—Robert W. Ramsuer
`Assistant Examiner—Jane C. OsWecki
`Attorney, Agent, or Firm—Joseph J. Borovian
`
`[57]
`
`ABSTRACT
`
`The present invention relates to a compound of formula (I)
`
`555 824 A1 8/1993
`1581 09 12/1982
`296 075 A5 11/1991
`WO90/ 12005 10/1990
`WO91/16339 10/1991
`WO93/08259 4/1993
`WO95/11689 5/1995
`WO95/13069 5/1995
`WO95/15309 6/1995
`WO95/29190 11/1995
`WO95/29691 11/1995
`WO95/34538 12/1995
`WO98/19998 5/1998
`WO99/38501 8/1999
`
`European Pat. Off. .
`Germany .
`Germany .
`
`WIPO .
`
`WIPO .
`
`WIPO .
`
`WIPO .
`
`WIPO .
`
`WIPO .
`
`WIPO .
`
`WIPO .
`
`WIPO .
`
`WIPO .
`
`WIPO .
`
`OTHER PUBLICATIONS
`
`Li, et al. Archives of Biochemistry and Biophysics, vol. 323,
`No. 1, pp. 148—154 (1995).
`
`Li, et al. Journal of Neurochemistry, vol. 66, pp. 2105—2112
`(1996).
`
`Wherein R is substituted adamantyl; and n is 0 to 3; in free
`form or in acid addition salt form. Compounds of formula I
`inhibit DPP-IV (dipeptidyl-peptidase-IV) activity. They are
`therefore indicated for use as pharmaceuticals in inhibiting
`DPP-IV and in the treatment of conditions mediated by
`DPP-IV, such as non-insulin-dependent diabetes mellitus,
`arthritis, obesity, osteoporosis and further conditions of
`impaired glucose tolerance.
`
`9 Claims, N0 Drawings
`
`AstraZeneca Exhibit 2013
`Mylan v. AstraZeneca
`IPR2015-01340
`
`Page 1 of 12
`
`

`
`6,166,063
`
`1
`N-(SUBSTITUTED GLYCYL)-2
`CYANOPYRROLIDINES,
`PHARMACEUTICAL COMPOSITIONS
`CONTAINING THEM AND THEIR USE IN
`INHIBITING DIPEPTIDYL PEPTIDASE-IV
`
`This application claims the bene?t of Us. application
`Ser. No. 09/209,068, ?led Dec. 10, 1998, noW abandoned,
`and Which is incorporated herein by reference.
`The present invention provides neW dipeptidyl
`peptidase-IV (DPP-IV) inhibitors Which are effective in
`treating conditions mediated by DPP-IV. More recently, it
`Was discovered that DPP-IV is responsible for inactivating
`glucagon-like peptide-1 (GLP-l). Since GLP-1 is a major
`stimulator of pancreatic insulin secretion and has direct
`bene?cial effects on glucose disposal, DPP-IV inhibition
`appears to represent an attractive approach for treating
`conditions such as non-insulin-dependent diabetes mellitus
`(NIDDM).
`The instant invention relates to novel N-(substituted
`glycyl)-2-cyanopyrrolidines of formula I:
`
`Wherein
`R is substituted adamantyl; and
`n is 0 to 3; in free form or in acid addition salt form.
`The compounds of formula I can eXist in free form or in
`acid addition salt form. Pharmaceutically acceptable (i.e.,
`non-toXic, physiologically acceptable) salts are preferred,
`although other salts are also useful, e.g., in isolating or
`purifying the compounds of this invention. Although the
`preferred acid addition salts are the hydrochlorides, salts of
`methanesulfonic, sulfuric, phosphoric, citric, lactic and ace
`tic acid may also be utiliZed.
`The compounds of the invention may eXist in the form of
`optically active isomers or diastereoisomers and can be
`separated and recovered by conventional techniques, such as
`chromatography.
`Listed beloW are de?nitions of various terms used to
`describe this invention. These de?nitions apply to the terms
`as they are used throughout this speci?cation, unless other
`Wise limited in speci?c instances, either individually or as
`part of a larger group.
`The term “alkyl” refers to straight or branched chain
`hydrocarbon groups having 1 to 10 carbon atoms, preferably
`1 to 7 carbon atoms, most preferably 1 to 5 carbon atoms.
`Exemplary alkyl groups include methyl, ethyl, propyl,
`isopropyl, n-butyl, t-butyl, isobutyl, pentyl, heXyl and the
`like.
`The term “alkanoyl” refers to alkyl-C(O)—.
`The term “substituted adamantyl” refers to adamantyl,
`i.e., 1- or 2-adamantyl, substituted by one or more, for
`eXample tWo, substitutents selected from alkyl, —OR1 or
`—NR2R3; Where R1, R2 and R3 are independently hydrogen,
`alkyl, (C1—C8-alkanoyl), carbamyl, or —CO—NR4R5;
`Where R4 and R5 are independently alkyl, unsubstituted or
`substituted aryl and Where one of R4 and R5 additionally is
`hydrogen or R4 and R5 together represent C2—C7alkylene.
`The term “aryl” preferably represents phenyl. Substituted
`phenyl preferably is phenyl substituted by one or more, e.g.,
`tWo, substitutents selected from, e.g., alkyl, alkoXy, halogen
`and tri?uoromethyl.
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`55
`
`60
`
`2
`The term “alkoXy” refers to alkyl-O—.
`The term “halogen” or “halo” refers to ?uorine, chlorine,
`bromine and iodine.
`The term “alkylene” refers to a straight chain bridge of 2
`to 7 carbon atoms, preferably of 3 to 6 carbon atoms, most
`preferably 5 carbon atoms.
`A preferred group of compounds of the invention is the
`compounds of formula I Wherein the substituent on the
`adamantyl is bonded on a bridgehead or a methylene adja
`cent to a bridgehead. Compounds of formula I Wherein the
`the glycyl-2-cyanopyrrolidine moiety is bonded to a
`bridgehead, the R‘ substituent on the adamantyl is preferably
`3-hydroXy. Compounds of formula I Wherein the the glycyl
`2-cyanopyrrolidine moiety is bonded at a methylene adja
`cent to a bridgehead, the R‘ substituent on the adamantyl is
`preferably S-hydroxy.
`The present invention especially relates to a compound of
`formulae (I A) or (I B)
`
`R,
`
`V
`
`R
`
`R"
`
`R,
`
`
`
`T N\)i\ N O
`
`
`
`(IA)
`
`(113)
`
`N
`
`N
`
`PII
`
`O
`
`N\)i\ I: ‘Q
`
`Wherein R‘ represents hydroXy, C1—C7alkoXy, C1—C8
`alkanoyloXy, or R5R4N—CO—O—, Where R4 and R5 inde
`pendently are C1—C7alkyl or phenyl Which is unsubstituted
`or substituted by a substitutent selected from C1—C7alkyl,
`C1—C7alkoXy, halogen and tri?uoromethyl and Where R4
`additionally is hydrogen; or R4 and R5 together represent
`C3—C6alkylene; and R“ represents hydrogen; or R‘ and R“
`independently represent C1—C7alkyl; in free form or in form
`of a pharmaceutically acceptable acid addition salt.
`The compounds of the invention may be prepared eg by
`a process Which comprises coupling a reactive
`(2-cyanopyrrolidino)carbonylmethylene compound With an
`appropriate substituted amine; more particularly, for the
`preparation of the compounds of formula I, it comprises
`reacting a compound of formula II.
`
`Wherein Y is a reactive group (preferably a halogen such as
`bromine, chlorine or iodine) With a compound of formula III
`
`65
`
`Wherein R is as de?ned above, and recovering the resultant
`compound of formula I in free form or in acid addition salt
`form.
`
`Page 2 of 12
`
`

`
`3
`The process of the invention may be effected in conven
`tional manner. For example, the compound of formula II is
`reacted With 1 to 3 equivalents, preferably 3 equivalents, of
`a primary amine of formula III. The reaction is conveniently
`conducted in the presence of an inert, organic solvent, such
`as methylene chloride or a cyclic ether such as tetrahydro
`furan. The temperature preferably is of from about 0° to
`about 35° C., preferably betWeen about 0° and about 25° C.
`The compounds of the invention may be isolated from the
`reaction mixture and puri?ed in conventional manner, eg
`by chromatography.
`The starting materials may also be prepared in conven
`tional manner. The compounds of formula II may be pre
`pared by the folloWing tWo-step reaction scheme:
`
`STEP 1
`
`IL
`
`a“
`.. \
`
`‘I1
`
`C
`Y
`NHZ V \Y
`
`IV
`
`STEP 2
`
`TFAA
`(at least 2 eq.)
`
`V
`
`Step 1 involves the reaction of the pyrrolidine of formula
`IV With a slight molar excess of a haloacetylhalide such as
`bromoacetylbromide or chloroacetylchloride and a base
`such as potassium carbonate or triethylamine. The reaction
`conveniently is conducted in the presence of an inert,
`organic solvent, such as tetrahydrofuran or a chlorinated,
`aliphatic hydrocarbon such as methylene chloride, at a
`temperature of from about 0° to about 25° C., preferably at
`a temperature betWeen about 0° and about 15° C.
`Step 2 concerns the dehydration of the compound of
`formula V, prepared in Step 1, With 1 to 2 equivalents of
`tri?uoroacetic anhydride
`The dehydration prefer
`ably is conducted in the presence of an inert, organic solvent
`such as tetrahydrofuran or a chlorinated, aliphatic hydrocar
`bon such as methylene chloride, at a temperature of from
`about 0° to about 25° C., preferably at a temperature
`betWeen about 0° and about 15° C.
`Insofar as its preparation is not particularly described
`herein, a compound used as starting material is knoWn or
`may be prepared from knoWn compounds in knoWn manner
`or analogously to knoWn methods or analogously to methods
`described in the Examples.
`For example, the primary amine compounds of formula
`III are knoWn and may be prepared by procedures docu
`mented in the literature, for example, Khim. -Farm. Zh.
`(1986), 20(7), 810—15.
`Finally, compounds of the invention are either obtained in
`the free form, or as a salt thereof if salt forming groups are
`present.
`Compounds of the invention having basic groups can be
`converted into acid addition salts, especially pharmaceuti
`cally acceptable acid addition salts. These are formed, for
`example, With inorganic acids, such as mineral acids, for
`example sulfuric acid, a phosphoric or hydrohalic acid, or
`With organic carboxylic acids. Preferred are salts formed
`With hydrochloric acid.
`
`6,166,063
`
`4
`In vieW of the close relationship betWeen the free com
`pounds and the compounds in the form of their salts,
`Whenever a compound is referred to in this context, a
`corresponding salt is also intended, provided such is pos
`sible or appropriate under the circumstances.
`The compounds, including their salts, can also be
`obtained in the form of their hydrates, or include other
`solvents used for their crystalliZation.
`The instant invention also includes pharmaceutical
`compositions, for example, useful in inhibiting DPP-IV,
`comprising a pharmaceutically acceptable carrier or diluent
`and a therapeutically effective amount of a compound of
`formula I, or a pharmaceutically acceptable acid addition
`salt thereof.
`In still another embodiment, the instant invention pro
`vides a method of inhibiting DPP-IV comprising adminis
`tering to a mammal in need of such treatment a therapeuti
`cally effective amount of a compound of formula I, or a
`pharmaceutically acceptable acid addition salt thereof.
`In a further embodiment, the instant invention provides a
`method of treating conditions mediated by DPP-IV inhibi
`tion comprising administering to a mammal in need of such
`treatment a therapeutically effective amount of a compound
`of formula I above, or a pharmaceutically acceptable acid
`addition salt thereof.
`The present invention also relates to the use of a com
`pound according to the instant invention or a pharmaceuti
`cally acceptable salt thereof, e.g., for the manufacture of a
`medicament for the prevention or treatment of diseases or
`conditions associated With elevated levels of DPP-IV.
`As indicated above, all of the compounds of formula I,
`and their corresponding pharmaceutically acceptable acid
`addition salts, are useful in inhibiting DPP-IV. The ability of
`the compounds of formula I, and their corresponding phar
`maceutically acceptable acid addition salts, to inhibit DPP
`IV may be demonstrated employing the Caco-2 DPP-IV
`Assay Which measures the ability of test compounds to
`inhibit DPP-IV activity from human colonic carcinoma cell
`extracts. The human colonic carcinoma cell line Caco-2 Was
`obtained from the American Type Culture Collection (AT CC
`HTB 37). Differentiation of the cells to induce DPP-IV
`expression Was accomplished as described by Reisher, et al.
`in an article entitled “Increased expression of intestinal cell
`line Caco-2” in Proc. Natl. Acad. Sci., Vol. 90, pgs.
`5757—5761 (1993). Cell extract is prepared from cells solu
`biliZed in 10 mM Tris HCl, 0.15 M NaCl, 0.04 t.i.u.
`aprotinin, 0.5% nonidet-P40, pH 8.0, Which is centrifuged at
`35,000 g for 30 min. at 4° C. to remove cell debris. The assay
`is conducted by adding 20 pg solubiliZed Caco-2 protein,
`diluted to a ?nal volume of 125 pl in assay buffer (25 mM
`Tris HCl pH 7.4, 140 mM NaCl, 10 mM KCl, 1% bovine
`serum albumin) to microtiter plate Wells. After a 60 min.
`incubation at room temperature, the reaction is initiated by
`adding 25 pl of 1 mM substrate (H-Alanine-Proline-pNA;
`pNA is p-nitroaniline). The reaction is carried out at room
`temperature for 10 minutes after Which time a 19 pl volume
`of 25% glacial acetic acid is added to stop the reaction. Test
`compounds are typically added as 30 pl additions and the
`assay buffer volume is reduced to 95 pl. Astandard curve of
`free p-nitroaniline is generated using 0—500 pM solutions of
`free pNA in assay buffer. The curve generated is linear and
`is used for interpolation of substrate consumption (catalytic
`activity in nmoles substrate cleaved/min). The endpoint is
`determined by measuring absorbance at 405 nm in a
`Molecular Devices UV Max microtiter plate reader.
`The potency of the test compounds as DPP-IV inhibitors,
`expressed as ICSO, is calculated from 8-point, dose-response
`curves using a 4-parameter logistic function.
`
`10
`
`15
`
`20
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`Page 3 of 12
`
`

`
`5
`The following IC5O Was obtained:
`
`Compound
`
`Caco-2 DPP-IV (nM)
`
`Ex. 1
`Ex. 4
`
`3.5 r 1.5
`8
`
`The ability of the compounds of formula I, and their
`corresponding pharmaceutically acceptable acid addition
`salts, to inhibit DPP-IV may also be demonstrated by
`measuring the effects of test compounds on DPP-IV activity
`in human and rat plasma employing a modi?ed version of
`the assay described by Kubota, et al. in an article entitled
`“Involvement of dipeptidylpeptidase IV in an in vivo
`immune response” in Clin. Exp. Immunol., Vol. 89, pgs.
`192—197 (1992). Brie?y, 5 pl of plasma are added to 96-Well
`?at-bottom microtiter plates (Falcon), folloWed by the addi
`tion of 5 pl of 80 mM MgCl2 in incubation buffer (25
`mMHEPES, 140 mM NaCl, 1% RIA-grade BSA, pH 7.8).
`After a 60 min. incubation at room temperature, the reaction
`is initiated by the addition of 10 pl of incubation buffer
`containing 0.1 mM substrate (H-Glycine-Proline
`AMC;AMC is 7-amino-4-methylcoumarin). The plates are
`covered With aluminum foil (or kept in the dark) and
`incubated at room temperature for 20 min. After the 20 min.
`reaction, ?uorescence is measured using a CytoFluor 2350
`?uorimeter (Excitation 380 nm Emission 460 nm; sensitivity
`setting 4). Test compounds are typically added as 2 pl
`additions and the assay buffer volume is reduced to 13 pl. A
`?uorescence-concentration curve of free AMC is generated
`using 0—50 pM solutions of AMC in assay buffer. The curve
`generated is linear and is used for interpolation of substrate
`consumption (catalytic activity in nmoles substrate cleaved/
`min). As With the previous assay, the potency of the test
`compounds as DPP-IV inhibitors, expressed as ICSO, is
`calculated from 8-point, dose-response curves using a 4
`parameter logistic function.
`The folloWing IC5O Was obtained:
`
`15
`
`25
`
`35
`
`Compound
`
`human plasma DPP-IV (nM) rat plasma DPP-IV (nM)
`
`Ex. 1
`Ex. 8
`
`2.7 r 0.1
`6
`
`2.3 r 0.1
`12
`
`45
`
`In vieW of their ability to inhibit DPP-IV, the compounds
`of formula I, and their corresponding pharmaceutically
`acceptable acid addition salts, are useful in treating condi
`tions mediated by DPP-IV inhibition. Based on the above
`and ?ndings in the literature, it is expected that the com
`pounds disclosed herein are useful in the treatment of
`conditions such as non-insulin-dependent diabetes mellitus,
`arthritis, obesity, allograft transplantation and calcitonin
`osteoporosis. In addition, based on the roles of glucagon-like
`peptides (such as GLP-1 and GLP-2) and their association
`With DPP-IV inhibition, it is expected that the compounds
`disclosed herein are useful for example, to produce a seda
`tive or anxiolytic effect, or to attenuate post-surgical cata
`bolic changes and hormonal responses to stress, or to reduce
`mortality and morbidity after myocardial infarction,or in the
`treatment of conditions related to the above effects Which
`may be mediated by GLP-1 and/or GLP-2 levels.
`More speci?cally, for example, the compounds of formula
`I, and their corresponding pharmaceutically acceptable acid
`addition salts, improve early insulin response to an oral
`glucose challenge and, therefore, are useful in treating
`
`55
`
`65
`
`6,166,063
`
`6
`non-insulin-dependent diabetes mellitus. The ability of the
`compounds of formula I, and their corresponding pharma
`ceutically acceptable acid addition salts, to improve early
`insulin response to an oral glucose challenge may be mea
`sured in insulin resistant rats according to the folloWing
`method:
`Male Sprague-DaWley rats that had been fed a high fat
`diet (saturated fat=57% calories) for 2—3 Weeks Were fasted
`for approximately 2 hours on the day of testing, divided into
`groups of 8—10, and dosed orally With 10 pmol/kg of the test
`compounds in CMC. An oral glucose bolus of 1 g/kg Was
`administered 30 minutes after the test compound directly
`into the stomach of the test animals. Blood samples,
`obtained at various timepoints from chronic jugular vein
`catheters, Were analyZed for plasma glucose and immunore
`active insulin (IRI) concentrations, and plasma DPP-IV
`activity. Plasma insulin levels Were assayed by a double
`antibody radioimmunoassay (RIA) method using a speci?c
`anti-rat insulin antibody from Linco Research (St. Louis,
`M0). The RIA has a loWer limit of detection of 0.5 pU/mL
`With intra- and inter-assay variations of less than 5%. Data
`are expressed as % increase of the mean of the control
`animals. Upon oral administration, each of the compounds
`tested ampli?ed the early insulin response Which led to an
`improvement in glucose tolerance in the insulin resistant test
`animals. The folloWing results Were obtained:
`
`Compound
`
`Ex. 1
`
`Increase of Insulin Response
`at 10 ,umol/kg
`
`64%
`
`The precise dosage of the compounds of formula I, and
`their corresponding pharmaceutically acceptable acid addi
`tion salts, to be employed for treating conditions mediated
`by DPP-IV inhibition depends upon several factors, includ
`ing the host, the nature and the severity of the condition
`being treated, the mode of administration and the particular
`compound employed. HoWever, in general, conditions medi
`ated by DPP-IV inhibition are effectively treated When a
`compound of formula I, or a corresponding pharmaceuti
`cally acceptable acid addition salt, is administered enterally,
`e.g., orally, or parenterally, e.g., intravenously, preferably
`orally, at a daily dosage of 0.002—5, preferably 0.02—2.5
`mg/kg body Weight or, for most larger primates, a daily
`dosage of 0.1—250, preferably 1—100 mg. A typical oral
`dosage unit is 0.01—0.75 mg/kg, one to three times a day.
`Usually, a small dose is administered initially and the dosage
`is gradually increased until the optimal dosage for the host
`under treatment is determined. The upper limit of dosage is
`that imposed by side effects and can be determined by trial
`for the host being treated.
`The compounds of formula I, and their corresponding
`pharmaceutically acceptable acid addition salts, may be
`combined With one or more pharmaceutically acceptable
`carriers and, optionally, one or more other conventional
`pharmaceutical adjuvants and administered enterally, e.g.,
`orally, in the form of tablets, capsules, caplets, etc. or
`parenterally, e.g., intravenously, in the form of sterile inject
`able solutions or suspensions. The enteral and parenteral
`compositions may be prepared by conventional means.
`The compounds of formula I, and their corresponding
`pharmaceutically acceptable acid addition salts, may be
`formulated into enteral and parenteral pharmaceutical com
`positions containing an amount of the active substance that
`is effective for treating conditions mediated by DPP-IV
`
`Page 4 of 12
`
`

`
`6,166,063
`
`7
`inhibition, such compositions in unit dosage form and such
`compositions comprising a pharmaceutically acceptable car
`r1er.
`The compounds of formula I (including those of each of
`the subscopes thereof and each of the examples) may be
`administered in enantiomerically pure form (e.g., ee >98%,
`preferably >99%) or together With the R enantiomer, e.g., in
`racemic form. The above dosage ranges are based on the
`compounds of formula I (excluding the amount of the R
`enantiomer).
`10
`The folloWing examples shoW representative compounds
`encompassed by this invention and their synthesis.
`HoWever, it should be clearly understood that they are for
`purposes of illustration only.
`EXAMPLE 1
`Pyrrolidine , 1 -[(3-hydroxy- 1 -adamantyl)amino ]acetyl-2
`cyano-, (S)
`
`15
`
`HO
`
`H
`
`O
`
`N
`
`I \i
`
`N
`
`20
`
`25
`
`8
`is stirred at 14—15° C. for 20 min, the temperature is alloWed
`to raise to 25° C. over 1 h (hour) (15—20° C. for 30 min, and
`20—25° C. for 30 min), then the contents a stirred at 24—25.5°
`C. for 5 h (external cooling is needed). 1.7 L of Water are
`charged into a 5 -L, 4-necked ?ask, the Water is cooled to 10°
`C., then the reaction mixture is sloWly poured (very
`exothermic, some NO2 gas evolution) over 25 min. main
`taining the internal temperature beloW 35° C. to give a
`blue-green homogenous solution. The original 2-L ?ask
`(slightly exothermic) is rinsed once With 0.3 L of Water and
`the Water Wash is poured into the 5-L ?ask. SloWly 900 mL
`of 50% sodium hydroxide aqueous solution are added (very
`exothermic, some NO2 gas evolution) into the 5-L ?ask over
`30 min. at 65—70° C. to bring the pH of the mixture to 13.
`800 mL of 1-butanol and 200 mL of toluene are added (not
`exothermic) under vigorous stirring and alloW the mixture to
`reach 30° C. The bottom aqueous layer is separated for
`proper disposal. The organic layer is once Washed With 100
`mL of saturated sodium chloride solution. The saturated
`sodium chloride Wash is saved for disposal. The organic
`layer is concentrated at 60—85° C. (20—200 mbar) to give a
`pale yelloW viscous oil. 600 mL of heptane and 50 mL of
`methanol are added into and the mixture is maintained at
`40—50° C. for 15 min to give a thick suspension. The slurry
`is cooled to 12° C. and maintained at 12—14° C. for 15 min.
`The solids are ?ltered off through a polypropylene pad and
`Buchner funnel, then the ?ask and ?lter cake are Washed
`once With 80 mL of heptane. The methanol/heptane ?ltrate
`is saved. The ?lter cake is dried at 55—60° C. (30 mbar) for
`16 h to afford 1-aminoadamantane-3-ol as an off-White solid.
`B. 1-Chloroacetyl-2-cyanopyrrolidine
`To a mechanically stirred solution of 20.0 g (180.0 mmol)
`of chloroacetylchloride and 97 g (0.70 mmol) of potassium
`carbonate in 150 mL of tetrahydrofuran is added a solution
`of L-prolinamide 20.0 g (180.0 mmol) in 500 mL of tet
`rahydrofuran in a dropWise fashion over 45 minutes. This
`reaction is then mechanically stirred for an additional tWo
`hours at room temperature. The reaction is then ?ltered to
`remove potassium salts and the ?ltrate is dried over Na2SO4.
`The NaZSO4 is then removed via ?ltration and to this
`colorless ?ltrate is added tri?uoroacetic anhydride (25.0 mL,
`0.180 mmol) in one portion. The reaction is then magneti
`cally stirred for 1 hour at room temperature and the resulting
`clear yelloW/orange solution is concentrated via rotovap.
`The excess tri?uoroacetic anhydride is removed by adding
`ethyl acetate to the concentrated oil and reconcentrating via
`rotovap. This removing operation is performed three times.
`The resulting oil is partitioned betWeen ethyl acetate and
`Water. The product is then extracted into the ethyl acetate
`and the aqueous layer is then Washed tWice With ethyl
`acetate. The combined organic layers are then Washed
`successively With Water and brine dried over magnesium
`sulfate, ?ltered and concentrated to obtain 1-chloroacetyl
`2-cyanopyrrolidine as a yelloW solid.
`Alternatively, the reaction may be carried out by using, as
`base, a mixture, e.g. 2-ethyl-hexanoic acid/sodium hydride.
`C. Pyrrolidine, 1-[(3-hydroxy-1-adamantyl)amino]acetyl-2
`cyano-, (S)
`To a heterogeneous solution of the title A compound
`(1-aminoadamantane-3-ol (5.80 g, 34.7 mmol) in CHZCl2
`(68.0 mL) is added 9.6 g (69 mmol) of K2CO3. This
`heterogeneous mixture is then cooled in an ice-Water bath
`and a solution of 3.0 g (17 mmol) of the title B compound
`(1-chloroacetyl-2-cyanopyrrolidine) dissolved in 25.0 mL of
`CHZCl2 is added dropWise over a period of 30 minutes. The
`resulting mixture is stirred for 2 hours at 0° C. and at room
`temperature for 6 days. The reaction is then concentrated to
`
`A. 1-Aminoadamantane-3-ol
`Slight modi?cations to the synthesis found in Khim.
`-Farm. Zh. (1986), 20(7), 810—15, may be used.
`To a rapidly stirred, clear and colorless, ice-Water chilled
`mixture of concentrated sulfuric acid 96% (210 mL; 3,943
`mmol) and 65% nitric acid (21.0 mL; 217.0 mmol) is added
`21.0 g (112.0 mmol) of 1-adamantylamine HCl (99%), in
`small portions over 30 minutes. Upon adamantylamine
`hydrochloride addition, slight bubbling occurs and the reac
`tion is slightly exothermic. This bubbling, yelloW solution is
`stirred at ice-Water temperature for about 2 hours and then
`at room temperature for 30 hours. This clear, light yelloW
`reaction is then poured into about 100 g of ice and the
`resulting solution is clear green-blue.
`The solution is placed in an ice-Water bath and alloWed to
`stir for 30 minutes. Approximately 550 g of 89% pure KOH
`(8.74 mol) is then added in small portions over 45 minutes.
`During this addition, the reaction is exothermic; reaching
`800 C. and producing copious amounts of broWn NO2 gas.
`By the end of the addition, the reaction is thick With White
`solids (both product and salts). The resulting White paste is
`then poured onto a buchner funnel/celite pad and Washed
`With 1.2 L of CH2Cl2. The CHZCl2 layer is then extracted
`from the Water layer and dried over Na2SO4. The solution is
`then ?ltered and concentrated (rotovap/pump) to provide
`1-aminoadamantane-3-ol as a White solid.
`Alternatively, the reaction may be carried out using
`n-butanol as solvent instead of methylene chloride.
`Alternatively, 1-aminoadamantane-3-ol can be prepared
`eg as folloWs: A 2-L, 4-necked, round-bottomed ?ask is
`thoroughly ?ushed With nitrogen. The ?ask is charged under
`nitrogen With 420 mL of conc. sulfuric acid (98%). The
`contents are cooled to 80 C., then sloWly (slightly exother
`mic & HCl gas evolution) 100.8 g of 1-aminoadamantane
`hydrochloride are added into the mixture in 8 portions at
`9—10° C. over 20 min (minutes), then the haZy contents are
`stirred at 9—10° C. for 20 min to obtain a homogenous
`mixture. 72 mL of conc. (concentrated) nitric acid (70%) are
`added (very exothermic) dropWise into the mixture main
`taining inner temperature at 14—15° C. With ef?cient cooling
`(at this scale 20 min. needed for this addition). The mixture
`
`30
`
`35
`
`40
`
`45
`
`55
`
`60
`
`65
`
`Page 5 of 12
`
`

`
`6,166,063
`
`10
`9
`Alternatively, the reaction may be carried out using tet
`obtain a yellow pasty material Which is puri?ed on silica gel
`rahydrofuran as solvent instead of methylene chloride;
`employing a SIMS/Bimage Flash Chromatography System
`furthermore, the Chromatography Step may be eliminated
`and a 7% solution of methanol in methylene chloride as the
`EXAMPLES 2 TO 12
`eluent to yield the title compound in free base form as a
`White crystalline solid (melting point 138° C.—140° C., 5 The following compounds are prepared analogous to the
`13CNMR (ppm)=119.59).
`method of Example 1 (especially Step C):
`
`Structure
`
`Hchiml
`//
`§3
`
`0
`
`N\k N
`
`M.P. [0 C.]
`
`103-105
`(HCl)
`
`Pyrrolidine, 1—[[(3,5-dimethyl—1—adamantyl)amino]—
`acetyl]—2—cyano—, (S)
`
`Example
`
`2
`
`3
`
`4
`
`NChiJal
`//
`§3
`i
`
`0
`
`H
`
`NA N
`
`Pyrrolidine, 1—[[(3—ethyl—1-adamantyl)amino]acetyl]—
`2—oyano—, (S)
`
`0
`
`N //
`$C
`i
`
`O
`
`H
`
`N
`
`Pyrrolidine, 1—[[(3-methoxy-1—adamantyl)amino]—
`acetyl]—2—cyano—, (S)
`
`212-214
`(HCl)
`
`92-94
`(HCl)
`
`Err
`
`5 a 1
`Q ///N
`
`N
`H
`
`O
`
`O
`
`"HO
`H\)]\ a
`N o N
`
`Page 6 of 12
`
`

`
`6,166,063
`
`12
`
`Example
`
`/O
`
`-continued
`
`Structure
`
`0
`
`N)J\OH
`
`M.P. [° C.]
`
`Chm
`
`212-214
`(HC1)
`
`
`
`Pyrrolidine, 1-[[[3-[[[(4-rnethoXypheny1)arnino]-
`carbony1]oXy]-1-adarnanty1]arnino]acety1]-2-cyano-,
`(s)-
`
`205-207
`(HC1)
`
`Chiral
`
`N
`//
`‘=3
`
`0
`
`N
`
`0
`
`NH
`
`Pyrrolidine, 1-[[[(3-[[(pheny1arnino)carbony1]oXy]-1-
`adarnanty1]arnino]acety1]-2-cyano-, (S)-
`
`O
`wk ..
`
`N
`
`N
`
`N
`//
`$C
`
`[13C NMR (CN
`group): 121.56
`(ppm)]
`<Hc1>
`
`[13C NMR (CN
`group): 118.54
`(ppm)]
`
`HO
`
`Pyrrolidine, 1 -[[ (5-hydroXy-2-adarnanty1)arnino]-
`acetyl]-2-cyano-, (S)-
`
`0 A
`
`0
`
`Pyrrolidine, 1-[[ (3-acety10Xy-1-adarnanty1)arnino]-
`acetyl]-2-cyano-, (S)-
`
`Page 7 of 12
`
`Page 7 of 12
`
`

`
`Example
`
`10
`
`6,166,063
`
`-continued
`
`Structure
`
`O
`
`i
`
`N
`
`O
`
`\
`
`_
`
`Chll'?l
`
`N
`.//
`i
`
`O
`
`H
`
`N
`
`M.P. [0 C.]
`
`148-150
`
`(Hcl)
`
`Pyrrolidine, 1—[[[3—[[[(diisopropyl)amino]carbonyl]—
`oxy]—1-adamantyl]amino]acetyl]—2—cyano—, (S)
`
`11
`
`O
`
`i
`ON 0
`
`H
`
`155-157
`
`(HCl)
`
`Ch 1
`
`“3
`
`N
`
`H
`
`F‘
`
`N
`
`Pyrrolidine, 1—[[[3—[[[(cyclohexyl)amino]carbonyl]—
`oxy]—1-adamantyl]amino]acetyl]—2—cyano—, (S)
`
`12
`
`Chiral
`
`[13C NMR (CN
`group): 119.31
`
`Q96
`
`(HCl) = as hydrochloride
`
`All HCl salts of ?nal products are prepared by passing
`HCl gas through a 0.1 Molar solution of the free base in
`tetrahydrofuran until solution is clearly acidic followed by
`removal of the solvent (rotovap/pump).
`The amino-adamantane starting materials are knoWn in
`the literature or can be prepared as folloWs:
`The manufacture of 3,5-dimethyl-1-adamantylamine is
`described in J. Med. Chem, 25; 1; 1982; 51—56.
`The manufacture of 3-ethyl-1-adamantylamine is
`described in J. Med. Chem, 25; 1; 1982; 51—56.
`3-Methoxy-1-adamantylamine can be prepared as folloWs
`To a stirred, ice-Water chilled suspension of potassium
`hydride (0.680 gm; 5 .95 mmol) in 15.0 ml of tetrahydofuran
`is added a mixture of 1-aminoadamantane-3-ol (1.00 g; 5.95
`mmol) and 15.0 ml of tetrahydrofuran dropWise over 30
`minutes. The resulting mixture is then stirred for an addition
`30 minutes and iodomethane (0.370 ml; 5 .95 mmol) is then
`added dropWise over one minute. The resulting opaque
`White reaction is then stirred at room temperature for 18
`hours. The mixture is then diluted With 50 ml of methylene
`chloride and ?ltered to remove the inorganic impurities. The
`?ltrate is then concentrated and puri?ed on silica gel
`
`45
`
`55
`
`60
`
`65
`
`employing a SIMS/Biotage apparatus and 19% methanol
`and 19% ammonium hydroxide in methylene chloride as
`eluent to yield 3-methoxy-1-adamantylamine as an opaque
`oil.
`Synthesis of 3-[[(tertbutylamino)carbonyl]oxy]-1
`aminoadamantane
`To a mixture of 1-aminoadamantane-3-ol (5.00 g; 30.0
`mmol) and potassium carbonate (6.20 g; 45 mmol) in 150 ml
`of tetrahydrofuran is added benZylchloroformate (4.70 g,
`33.0 mmol) in dropWise fashion over a 10 minute period.
`The mixture is then stirr