合成路线1

Elinogrel potassium is prepared as follows. Condensation of methyl 2-amino-4,5-difluorobenzoate (I) with 4-nitrophenyl chloroformate (II) in refluxing CH2Cl2 gives the 4-nitrophenyl carbamate (III), which is condensed with 4-(Boc-amino)aniline (IV) in the presence of Et3N in THF at 60-70 °C to yield the diaryl urea (V), which, without isolation, is cyclized to the quinazoline-2,4-dione (VI) upon treatment with methanolic NaOMe or DBU. Alternatively, diaryl urea (V) is prepared by treatment of anthranilate (I) with COCl2 in toluene to yield isocyanate (VII) and/or carbamoyl chloride (VIII), which are then condensed with 4-(Boc-amino)aniline (IV) in the presence of Et3N in DMF . Deprotection of the amino group in compound (VI) by removal of the Boc group by means of HCl in dioxane provides 3-(4-aminophenyl)-6,7-difluoroquinazoline-2,4(1H,3H)-dione hydrochloride (IX), which undergoes selective fluoride displacement with methylamine (X) in DMSO at 110 °C to provide 3-(4-aminophenyl)-6-fluoro-7-(methylamino)quinazoline-2,4(1H,3H)-dione (XI). Subsequent carbamoylation of the primary amino group of quinazoline (XI) with ethyl N-(5-chlorothien-2-ylsulfonyl)carbamate (XII) in refluxing DMSO or acetonitrile yields elinogrel (XIII) , which is finally converted to its potassium salt by treatment with KOH in acetonitrile/H2O at 45-55 °C .

合成路线2

3-Hydroxybenzaldehyde (I) was protected as the methoxyethoxymethyl ether derivative (II) by treatment with methoxyethoxymethyl chloride and diisopropyl ethyl amine. Subsequent condensation of (II) with dimethyloxosulfonium methylide, generated from oxosulfonium salt (III) and NaH, gave rise to the racemic epoxide (IV). Kinetic resolution by hydrolysis with (R,R)-N,N'-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminocobalt (III) acetate complex provided the (S)-diol (V) along with the unreacted (R)-epoxide (VI), which were separated by column chromatography. Opening of the desired (R)-epoxide (VI) with methanolic methylamine gave amino alcohol (VII). Finally, removal of the methoxyethoxymethyl group by refluxing in methanolic HCl furnished the title compound.

合成路线3

2) The condensation of N,N-diphenylcarbamoyl chloride (IV) with [13C]-labeled methylamine (V) gives the corresponding urea (VI), which by heating at 240 C is converted to the [13C]-labeled methyl isocyanate (VII). Finally, this compound is cyclized with the diazonium salt (VIII) (obtained by diazotation of 3-aminopyrazole-4-carbonitrile with NaNO2-HCl in the usual way) to afford temozolomide labeled at the methyl in the 3-position. 3) The preceding sequence performed with [15N]-labeled methylamine (X) gives urea (XI), isocyanate (XII) and finally temozolomide labeled at the N in the 3-position.

合成路线4

The bromination of tetraline (XIX) with Br2 in hexane gives trans-1,2-dibromotetraline (XX), which by treatment with H2O and NaHCO3 yields trans-2-bromotetralin-1-ol (XXI) [also obtained by reaction of 1,2-dihydronaphthalene (XXII) with 1,3-dibromo-5,5-dimethylhydantoin (DBDH) and perchloric acid]. The reaction of (XXI) with methylamine affords the intermediate epoxide (XXIII), which without isolation with more methylamine gives trans 1-(methylamino) tetralin-2-ol as a racemic mixture rac-(XXIV). The optical resolution of this mixture with (+)-L-tartaric acid yields the desired enantiomer (R,R)(XXIV), which is condensed with 2-bromoacetaldehyde dimethyl acetal (XXV) by means of K2CO3 in acetonitrile furnishing the chiral tertiary amine (XXVI). The cyclization of (XXVI) with BuLi and TsCl provides the intermediate aziridinium salt (XXVII), which without isolation, is condensed with 4-chloro-3-methoxyphenyl-magnesium bromide (X) in THF to give the chiral tertiary amine (XXVIII). The cyclization of (XXVIII) by means of methanesulfonic acid yields the chiral tetracyclic compound (XXIX), which is hydrogenated by means of BH3/t-Bu-NH2 to afford (6aS,13bR)(VIII). Finally, this compound is demethylated with 48% HBr in acetic acid. The chiral secondary amine (XXVI) can also be obtained as follows: The enantioselective epoxidation of 1,2-dihydronaphthalene (XXII) by means of a chiral manganese catalyst and sodium hypochlorite gives the chiral epoxide (1S,2R)(XXIII), which is cleaved with 2-(methylamino)acetaldehyde dimethylacetal (XXX) at 95 C in a pressure vessel to yield the desired chiral secondary amine (XXVI).

合成路线5

The condensation of bromoacetaldehyde dimethyl acetal (I) with methylamine (II) by means of KOH in refluxing ethylene glycol gives bis(2,2-dimethoxyethyl)methylamine (III), which is cyclized with acetonedicarboxylic acid (IV) and more methylamine (II), yielding 3,9-dimethyl-3,9-diazabicyclo[3.3.1]nonan-7-one (V). The reaction of (V) with hydroxylamine affords the corresponding oxime (VI), which is reduced with H2 over RaNi in ethanol giving endo-3,9-dimethyl-3,9-diazabicyclo[3.3.1]nonan-7-amine (VII). Finally, this compound is condensed with 1H-indazole-3-carbonyl chloride (VIII) by means of dimethylaminopyridine (DMAP) in pyridine.

合成路线6

Synthesis of the aminopyrazole intermediate (XIII): The reaction of butanal (I) with methylhydrazine (II) in dichloromethane in the presence of MgSO4 gives the corresponding hydrazide (III), which is alkylated with ethyl bromoacetate (IV) by means of the polymer-supported base 2-(tert-butylimino)-2-(diethylamino)-1,3-dimethylperhydro-1,3,2-diazaphosphorine (PS-BEMP) (V) and polymer-supported methylamine (VI) to yield the hydrazino ester (VII). Treatment of compound (VII) with an ion exchange tetramethylammonium cyanide resin (VIII) in refluxing ethanol containing a catalytic amount of HOAc affords the adduct (IX), which is dehydrogenated with Pd/C/cyclopentene or MnO2 and treated with a polymer-supported ethyl isocyanate resin (X) in order to eliminate the unreacted product, providing the hydrazone (XI). Cyclization of (XI) by means of PS-BEMP (V) in ethanol gives 4-amino-1-methyl-3-propyl-1H-pyrazole-5-carboxylic acid ethyl ester (XII), which is finally treated with ammonia in methanol to afford the desired pyrazolecarboxamide intermediate (XIII).

合成路线7

The reductocondensation of naltrexone (I) with N-methylbenzylamine (II) by means of sodium cyanoborohydride in THF gives the N-benzyl-N-methylaminomorphinan derivative (III), which is debenzylated by hydrogenation with H2 over Pd/C in methanol yielding the methylaminomorphinan (IV). Finally, this compound is acylated with 3(E)-(3-furyl)acryloyl chloride and NaOH, Na2CO3 or triethylamine in methanol, THF or chloroform. Alternatively, methylaminomorphinan (IV) can also be obtained by direct reductocondensation of naltrexone (I) with methylamine by means of H2 over PtO2 in methanol.

合成路线8

The reductocondensation of ethanolamine (I) with 3-methylbenzaldehyde (II) by means of NaBH4 gives N-(3-methylbenzyl)ethanolamine (III), which is treated with SOCl2 to yield the 2-chloroethyl derivative (IV). The reaction of (IV) with methylamine (V) affords N-methyl-N'-(3-methylbenzyl)ethane-1,2-diamine (VI), which is condensed with the pyrazole-carboxamide derivative (VII) to provide the unstable compound (VIII)?? (IX). The reduction of (IX) with NaBH4 gives the racemic amide (X), which is submitted to optical resolution by preferential crystallization to yield the (R)-isomer (XI) (1,2). The hydrogenation of (XI) with H2 over Pd/C in ethanol affords the debenzylated compound (XII), which is alkylated by reductocondensation with acetaldehyde (XIII) and NaBH4 in methanol to provide the chiral N-(1-ethyl-4'-methylperhydro-1,4-diazepin-6-(R)-yl)-1H-pyrazole-3-carboxamide (XIV). Finally, this compound is treated with refluxing aqueous HCl to give the corresponding 6(R)-amino derivative (XV).

合成路线9

Nolomirole is synthesized by acylation of (rac)-6-(methylamino)-5,6,7,8-tetrahydronaphthalene-1,2-diol, CHF-1024 (I) with isobutyryl chloride (II) in THF. Reductocondensation of 5,6-dimethoxy-2-tetralone (III) with methylamine (IV) by means of LiBH4 or NaBH4 gives N-(5,6-dimethoxy-1,2,3,4-tetrahydronaphthalen-2-yl)-N-methylamine (V), which is treated with 48% HBr at 110 C.

合成路线10

The condensation of 2,3-dimethoxybenzaldehyde (VI) with pyruvic acid (VII) by means of KOH in ethanol/water gives 4-(2,3-dimethoxyphenyl)-2-oxo-3-butenoic acid (VIII), which is reductocondensed with methylamine (IV) by means of H2 over Pd/C in ethanol/ acetic acid to yield 4-(2,3-dimethoxyphenyl)-2-methylamino)butyric acid (IX). Reaction of acid (IX) with benzyl chloroformate (X) and NaOH in water affords the carbamate (XI), which is treated with refluxing SOCl2 to provide 4-[2-(2,3-dimethoxyphenyl)ethyl]-3-methyloxazolidine-2,5-dione (XII). Reaction of oxazolidinone (XII) with AlCl3 in dichloromethane provides 5,6-dimethoxy-2-(methylamino)-1,2,3,4-tetrahydronaphthalen-1-one (XIII), which is reduced with H2 over Pd/C in ethanol containing some methanolic HCl in an autoclave at 80 C to yield N-(5,6-dimethoxy-1,2,3,4-tetrahydronaphthalen-2-yl)-N-methylamine (V). Finally, this compound is demethylated by treatment with AlCl3 in hot toluene. Alternatively, 5,6-dimethoxy-2-(methylamino)-1,2,3,4-tetrahydronaphthalen-1-one (XIII) can first be demethylated with 48% HBr to give 5,6-dihydroxy-2-(methylamino)-1,2,3,4-tetrahydronaphthalen-1-one (XIV), which is then reduced by means of H2 over Pd/C in an autoclave at 80 C.

合成路线11

Ring opening of cyclohexene oxide (I) with aqueous methylamine gave trans 2-(methylamino)cyclohexanol (II), which was further cyclized to the aziridine (III) upon treatment with chlorosulfonic acid and then with NaOH. Subsequent condensation of (III) with pyrrolidine (IV) yielded the racemic trans diamine (V). Resolution was achieved by fractional crystallization of the 2,3-di-p-toluoyl-D-tartaric acid salt in MeOH. The required (-)-(R,R) enantiomer was finally coupled with 4-benzothiopheneacetyl chloride (VI) to provide the corresponding amide.

合成路线12

3,3-Diphenylpropionic acid (I) was treated with SOCl2 to give acid chloride (II) and then converted to amide (III) using liquid ammonia. Dehydration with P2O5 led to diphenylpropionitrile (IV), which was treated with SOCl2 in methanol to afford the iminoester (V). The condensation of (V) wiith 2-oxobutan-1,4-diol (VI) in liquid ammonia furnished imidazole (VII). Further treatment of (VII) with SOCl2 provided chloride (VIII). Finally, reaction of (VIII) with methylamine in the presence of K2CO3 and a catalytic amount of KI afforded the title compound.

合成路线13

Condensation of bis(2-chloroethyl)phosphoramidic dichloride (I) with the sodium salt of 3-buten-1-ol (II) gave the O-butenyl phosphoramidate (III), which was subsequently reacted with methylamine to produce the phosphorodiamidate (IV). Ozonization of the double bond of (IV), followed by oxidative workup with H2O2 yielded aldehyde (V). This was finally condensed with 2-mercaptoethanesulfonic acid cyclohexylamine salt (VI) to furnish the title compound.

合成路线14

Reduction of 3-chloropropiophenone (I) with NaBH4 produced 3-chloro-1-phenyl-1-propanol (II). Subsequent Mitsunobu coupling of (II) with 2-(methylthio)phenol (III) in the presence of DEAD and PPh3 afforded ether (IV). Finally, substitution of the halogen of (IV) for methylamine provided the corresponding secondary amine.

合成路线15

The reductocondensation of tetrahydropyran-4-one (I) with methylamine (II) by means of H2 over Pd/C in methanol gives 4-(methylamino)tetrahydropyran (III), which is then alkylated with 4-nitrobenzyl bromide (IV) and K2CO3 in DMF to yield the tertiary amine (V). Finally, the nitro group of (V) is educed with SnCl2 and conc. aq. HCl to afford N-(4-aminobenzyl)-N-methyl-N-(tetrahydropyran-4-yl)amine, the target intermediate (VI).

合成路线16

Curtius rearrangement of arachidonic acid (I) in the presence of diphenyl phosphoryl azide in hot benzene gave isocyanate (II), which was coupled with methylamine to yield the title urea.

合成路线17

The intermediate naphthylmethyl amine (IV) was prepared from 1-naphthaldehyde (I) by two related procedures. Reduction of (II) with NaBH4 gave alcohol (II), which was converted to the corresponding chloride with SOCl2 and then condensed with methylamine. Alternatively, condensation of aldehyde (I) with methylamine using TiCl4 as the dehydrating reagent produced aldimine (III), which was then reduced to amine (IV) by means of NaBH4.

合成路线18

Aminotetralin (VIII) was obtained by reductive amination of the 2-tetralone (XIV) in the presence of NaBH3CN.

合成路线19

The condensation of N-Boc-N-methyl-D-phenylalanine (VIII) with methylamine by means of EDC and HOBt gave the corresponding amide (IX). After acid deprotection of the Boc group of (IX), the resulting amino compound (X) was coupled with N-Boc-N-methyl-D-naphthylalanine (XI) using EDC and HOAt to provide dipeptide (XII). The Boc protecting group of (XII) was further cleaved with trifluoroacetic acid to give (XIII).

合成路线20

2-Pyrrolidinone (I) was protected as the N-Boc derivative (II) and then alkylated with 3-bromo-2-methylpropene (III) in the presence of LDA to yield (IV). Further alkylation of (IV) with tert-butyl bromoacetate gave the dialkylated pyrrolidinone (V). Catalytic hydrogenation of the 2-methylpropenyl substituent of (V) produced the racemic isobutyl analogue (VI), which was resolved by means of chiral HPLC. The desired (S)-enantiomer (VII) was deprotected by treatment with magnesium ethoxide, affording pyrrolidinone (VIII). N-Alkylation of the pyrrolidinone (VIII) with triflate (IX) furnished adduct (X), which was hydrolyzed to carboxylic acid (XI) with methanolic NaOH. After activation of (XI) with carbonyl diimidazole, coupling with methylamine gave rise to amide (XII). Cleavage of the tert-butyl ester group of (XII) employing trifluoroacetic acid produced carboxylic acid (XIII). This was finally coupled with hydroxylamine using EDC and HOBt.

合成路线21

The reduction of omega-chloropropiophenone (I) with NaBH4 in ethanol gives 3-chloro-1-phenyl-1-propanol (II), which is treated with butyric anhydride and pyridine in dichloromethane yielding the corresponding racemic ester (III). The optical resolution of (III) with immobilized lipase B from Candida antarctica (CALB) affords a mixture of unreacted (S)-ester and (R)-alcohol (IV) that are separated by column chromatography. The condensation of alcohol (IV) with 2-methoxyphenol (V) by means of PPh3 and diethyl azodicarboxylate (DEAD) in THF gives the corresponding ether (VI), which is finally treated with methylamine in refluxing ethanol.

合成路线22

Alkylation of 4,5,6,7-tetrahydro-1,2-benzisoxazol-3-ol (I) with ethyl bromide in the presence of K2CO3 afforded the ethoxy derivative (II). Subsequent oxidation of (II) with sodium dichromate and H2SO4 provided the desired ketone (III) along with minor amounts of the isomeric 7-oxo compound (IV) that were separated by column chromatography. Conversion of (III) to the corresponding oxime (V), followed by reduction with aluminum amalgam yielded amine (VI). Resolution was achieved via formation of the diastereomeric amides with (R)-alpha-methoxyphenylacetyl chloride (VII) and isolation of the desired isomer (VIII) by preparative HPLC. Cleavage of amide and ether groups of (VIII) by means of HBr furnished (R)-4-amino-3-hydroxy-4,5,6,7-tetrahydro-1,2-benzisoxazole (IX). Protection as the corresponding tert-butyl carbamate, followed by N-methylation with CH3I and NaH provided intermediate (X). An alternative procedure for the preparation of intermediate (X) consisted in the reductive amination of ketone (III) with methylamine and NaBH3CN, followed by condensation of the resulting amine (XI) with the chiral acid chloride (VII) and chromatographic isolation of the desired diastereoisomer (XII). The alpha-methoxyphenylacetyl group of (XII) was then removed by an alternative method consisting in the treatment with lithium triethylborohydride to give the chiral amine (XIII). Cleavage of the ethyl ether group of (XIII) was effected by means of HBr in AcOH, and the resulting compound (XIV) was condensed with di-tert-butyl dicarbonate to produce carbamate (X). Subsequent reaction of (X) with pivaloyloxymethyl iodide (XV) in the presence of potassium tert-butoxide yielded the target O-alkylated compound (XVI) along with some N-alkylated regioisomer. The Boc protecting group of (XVI) was finally removed by treatment with trifluoroacetic acid.

合成路线23

2-Pyrrolidinone (I) was protected as the N-Boc derivative (II) and then alkylated with 3-bromo-2-methylpropene (III) in the presence of LDA to yield (IV). Further alkylation of (IV) with tert-butyl bromoacetate gave the dialkylated pyrrolidinone (V). Catalytic hydrogenation of the 2-methylpropenyl substituent of (V) produced the racemic isobutyl analogue (VI), which was resolved by means of chiral HPLC. The desired (S)-enantiomer (VII) was deprotected by treatment with magnesium ethoxide, affording pyrrolidinone (VIII). Triflate (XI) was obtained from D-phenyllactic acid (IX) by formation of the methyl ester (X) upon treatment with iodomethane, followed by reaction with trifluoromethanesulfonic anhydride and pyridine. N-Alkylation of the pyrrolidinone (VIII) with triflate (XI) furnished adduct (XII), which was hydrolyzed to carboxylic acid (XIII) with methanolic NaOH. After activation of (XIII) with carbonyl diimidazole, coupling with methylamine gave rise to amide (XIV). Cleavage of the tert-butyl ester group of (XIV) employing trifluoroacetic acid produced carboxylic acid (XV). This was finally coupled with hydroxylamine using EDC and HOBt.

合成路线24

The formylation of 3,5-dichloropyridine (I) with methyl formate (II), BuLi and DIEA in THF gives 3,5-dichloropyridine-4-carbaldehyde (III), which is treated with 4-bromophenol (IV) and potassium tert-butoxide in hot THF to yield the adduct (V). This compound, without isolation is cyclized with methyl 2-mercaptoacetate (VI) by means of Cs2CO3 to afford 4-(4-bromophenoxy)thieno[2,3-c]pyridine-2-carboxylic acid methyl ester (VII), which is hydrolyzed with LiOH in THF/water to provide the corresponding carboxylic acid (VIII). Finally, this compound is condensed with methylamine (IX) by means of EDC and HOBt in DMF to give the target amide. Alternatively, the target amide can also be obtained by direct reaction of methyl ester (VII) with methylamine (IX) in hot methanol in a sealed tube.

合成路线25

The condensation of tert-butoxycarbonylproline (I) with methylamine (II), isovaleraldehyde (III) and ethyl isocyanoacetate (IV) in methanol gives Boc-Pro-Me-Leu-Gly-OEt (V), which is separated from its diastereoisomer by chromatography over silica gel. The reaction of (V) with ammonia in cold methanol yields the corresponding amide (VI). Finally this compound is deprotected by treatment with dry HCl in ethyl acetate

合成路线26

The condensation of 4-bromophenyl-3-pyridyl ketone (I) with ethyl bromoacetate (II) by means of Zn in refluxing benzene gives ethyl 3-hydroxy-3-(3-pyridyl)-3-(4-bromophenyl)propionate (III), which is reduced with LiAlH4 in refluxing ethyl ether yielding 1-(3-pyridyl)-1-(4-bromophenyl)propane-1,3-diol (IV). Finally this compound is treated first with PBr3 and HBr in refluxing acetone, and then with methylamine (V) at 110 C in a pressure vessel

合成路线27

The condensation of 4-bromophenyl-3-pyridyl ketone (I) with ethyl bromoacetate (II) by means of Zn in refluxing benzene gives ethyl 3-hydroxy-3-(3-pyridyl)-3-(4-bromophenyl)propionate (III), which is converted into the corresponding methylamide (VI) by treatment with methylamine (V) in ethanol. This compound is reduced with NaBH4 in THF yielding 3-(3-pyridyl)-3-(4-bromophenyl)-3-hydroxy-N-methylpropylamine (VII), which is finally dehydrated by treatment with 50% H2SO4 at 110 C

合成路线28

Reductive cyclization of 6-fluoro-3-(2-nitroethyl)-1H-indole-4-carboxylic acid methyl ester (I) by means of Zn and HCl in methanol/water gives 8-fluoro-3,4,5,6-tetrahydro-1H-azepino[5,4,3-cd]indol-6-one (II), which is brominated by means of Pyr/HBr/Br2 in THF/dichloromethane to afford the 2-bromo derivative (III). Condensation of the brominated compound (III) with 4-formylphenylboronic acid (IV) by means of Pd(PPh3)4 and Na2CO3 in refluxing H2O/ethanol/toluene provides 8-fluoro-2-(4-formylphenyl)-3,4,5,6-tetrahydro-1H-azepino[5,4,3-cd]indol-6-one (V), which is finally reductocondensed with methylamine (VI) by means of NaBH4 (1). Scheme 1.

合成路线29

合成路线30

Iodination of 3-(trifluoromethyl)-2-pyridinol (I) with NIS in acetonitrile/DMF at 80 °C gives 5-iodo-3-(trifluoromethyl)-2-pyridinol (II), which is treated with POCl3 in DMF at 110 °C under microwave to yield 2-chloro-5-iodo-3-(trifluoromethyl)pyridine (III). Condensation of iodide (III) with 4-methoxybenzylamine (IV) in the presence of Pd2dba3, xantphos and t-BuONa in refluxing toluene or using Pd(OAc)2, BINAP, Et3N and Cs2CO3 in toluene under microwave provides secondary amine (V), which is reacted with Zn(CN)2 in the presence of Pd2dba3 and dppf in DMF at 130 °C to obtain nitrile (VI). N-Deprotection of compound (VI) by means of TFA in CH2Cl2 affords 5-amino-3-(trifluoromethyl)pyridine-2-carbonitrile (VII), which is condensed with thiophosgene (VIII) in CHCl3/H2O to yield 5-isothiocyanato-3-(trifluoromethyl)pyridine-2-carbonitrile (IX). Finally, isothiocyanate (IX) is submitted to cyclocondensation with nitrile (X) in DMF at 80 °C under microwave, followed by treatment with HCl in refluxing MeOH .
Synthesis of intermediate (X): Condensation of 2,4-difluorobenzoyl chloride (XI) with methylamine (XII) in THF produces 2,4-difluoro-N-methylbenzamide (XIII), which is condensed with 4-methoxybenzylamine (IV) in acetonitrile (1, 3, 4) or DMSO at 190 °C under microwave (2) to give the secondary amine (XIV). N-Deprotection of compound (XIV) by means of TFA in CH2Cl2 provides 4-amino-2-fluoro-N-methylbenzamide (XV), which is finally condensed with cyclobutanone (XVI) and NaCN in AcOH at 80 °C . Alternatively, amino nitrile (X) is obtained by direct condensation of fluoride (XIII) with 1-aminocyclobutanecarbonitrile (XVII) (prepared by Strecker reaction of cyclobutanone (XVI) with NaCN, NH4Cl and NH3 in the presence of MgSO4) .

合成路线31

Jones oxidation of 2-fluoro-4-methyl-1-nitrobenzene (XVIII) with CrO3 and H2SO4, followed by acetylation with Ac2O in AcOH yields the gemdiacetate (XIX), which by deacetylation with HCl in AcOH at 115 °C provides 3-fluoro-4-nitrobenzaldehyde (XX). Horner-Wadsworth-Emmons reaction of aldehyde (XX) with ethyl (diethoxyphosphoryl)acetate (XXI) using NaH in THF affords the unsaturated ester (XXII), which by fluoride substitution with methylamine (XXIII) in DMSO provides the nitro-aniline derivative (XXIVa) . Alternatively, condensation of 2,4-dichloro-1-nitrobenzene (XXV) with methylamine (XXIII) using Et3N in DMSO or THF yields 5-chloro-N-methyl-2-nitroaniline (XXVI), which is then subjected to Heck coupling with ethyl acrylate (XXVIIa), methyl acrylate (XXVIIb) or butyl acrylate (XXVIIa) in the presence of Pd(OAc)2, LiCl and DIEA in DMAc at 110 °C , or Pd2dba3, t-Bu3P and (c-Hex)2NMe at 110 °C to give the corresponding arylacrylates (XXIVa), (XXIVb) or (XXIVc). Reduction of the nitro group in compounds (XXIVa), (XXIVb) or (XXIVc) by means of SnCl2.2H2O in EtOH at 80 °C , H2 over Raney-Ni in toluene/MeOH or Na2S2O4 and K2CO3 in EtOH/H2O produces the corresponding diaminophenylacrylates (XXVIIIa) , (XXVIIIb) or (XXVIIIc) , which are finally condensed with 1-aminocyclo-butanecarboxylic acid hydrochloride (XXIX) in CH2Cl2 to provide the benzimidazole intermediates (IIIa) , (IIIb) or (XXX), the free base of intermediate (II) .
Similarly, intermediate (II) can be obtained by condensation of the diaminophenylacrylate (XXVIIIc) with N-Boc-1-aminocyclobutanecarboxylic acid (XXXI) using DCC in toluene, followed by N-deprotection and cyclization of the resulting amino amide (XXXII) with HCl in BuOH at 75 °C .

合成路线32

Uracil intermediate (I) is obtained as follows. Condensation of 2-fluoro-4-iodophenyl isocyanate (XIII) with cyclopropylamine (XIV) in Et2O , or alternatively reaction of 2-fluoro-4-iodoaniline (XV) with CDI in the presence of Et3N in DMF, followed by condensation with cyclopropylamine (XIV) affords disubstituted urea (XVI). Cyclization of urea (XVI) is treated with malonic acid (XVII) in the presence of AcCl in Ac2O at 60 °C affords the pyrimidine trione (XVIII), which is chlorinated using POCl3 in the presence of PhNMe2 and a catalytic amount of H2O at 90 °C to provide a mixture of 6-chloropyrimidine (XIX) and the corresponding regioisomer. Finally, chloropyrimidine (XIX) is treated with methylamine (XX) in EtOH at 80 °C .
In an alternative procedure, acylation of urea (XVI) with cyanoacetic acid (XXI) by means of MsCl in DMF yields the N-(cyanoacetyl)urea (XXII), which cyclizes in aqueous NaOH at 80 °C to yield the amino-pyrimidine derivative (XXIII). Condensation of amine (XXIII) with dimethylformamide dimethylacetal (XXIV) in DMF affords formamidine (XXV), which is finally reduced using NaBH4 in EtOH/t-BuOH .