合成路线1

合成路线2

By condensation of N-[3-(morpholinocarbonyl)-2(R)-(1-naphthylmethyl)propionyl-L-histidine methyl ester (I) with isopropyl 3(S)-amino-4-cyclohexyl-2(R)-hydroxybutyrate (II) by means of diphenyl phosphoryl azide (DPA) in DMF. The starting products are prepared as follows: The condensation of 3-(morpholinocarbonyl)-2(R)-(1-naphthylmethyl)propionic acid (III) and histidine methyl ester (IV) by means of DPA in DMF gives the substituted histidine ester (I). The hydrogenation of N-(tert-butoxycarbonyl)-L-phenylalanine (V) with H2 over Rh/Al2O3 gives N-(tert-butoxycarbonyl)-L-cyclohexylalanine (VI), which is reduced with borane to the corresponding alaninol (VII). Controlled oxidation of (VII) with SO3-pyridine in benzene-DMSO affords N-(tert-butoxycarbonyl)-L-cyclohexylalaninal (VIII), which by treatment with KCN followed by hydrolysis with concentrated HCl yields 3-amino-4-cyclohexyl-2-hydroxybutyric acid (IX). Finally, this compound is esterified with isopropanol and hydrochloric acid to the starting ester (II).

合成路线3

The starting product (II) is obtained as follows: The condensation of N-(tert-butoxycarbonyl)-L-phenylalanine (XI) with magnesium diethylmalonate (XII) by means of N,N'-carbonyldiimidazole in THF - DMSO gives 4(S)-(tert-butoxycarbonylamino)-3-oxo-4-phenylpentanoic acid ethyl ester (XIII), which by an asymetric hydrogenation with H2 and (R)-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl-Ruthenium complex in ethanol is converted into 4(S)-(tert-butoxycarbonylamino)-4(S)-hydroxy-5-phenylpentanoic acid ethyl ester (XIV). The hydrolysis of (XIV) with KOH in water - dioxane gives the corresponding free acid (XV), which is hydrogenated with H2 over Rh/Al2O3 in ethanol to yield N-(tert-butoxycarbonyl)cyclostatine (XVI).The condensation of (XVI) with 2-morpholinoethylamine (XVII) by means of triethylamine and diethylphosphoryl cyanide in THF affords the corresponding amide (XVIII), which is finally condensed with N-(tert-butoxycarbonyl)-3-(4-thiazolyl)-L-alanine (XIX) by means of a previous hydrolysis with HCl, followed by the condensation step with diethylphosphoryl cyanide in THF, to give the cyclostatine derivative (II).

合成路线4

The reduction of N-Boc-L-phenylalanine (XIII) with B2H6 in THF gives the expected alcohol (XIV), which is oxidized with SO3/pyridine to yield the corresponding aldehyde (XV). The cyclization of (XV) with 2-sulfanylethylamine (XVI) affords the thiazolidine (XVII), which is dehydrogenated by means of MnO2 to afford the thiazole derivative (XVIII). Finally, the amino group of (XVIII) is deprotected with HCl to afford the desired intermediate, 2-phenyl-1(S)-(2-thiazolyl)ethylamine (XIX).

合成路线5

The reduction of N-Boc-L-phenylalanine (XVI) with diborane in THF gives N-Boc-L-phenylalaninol (XVII), which is oxidized with SO3/pyridine in DMSO to yield N-Boc-L-phenylalaninal (XVIII). The cyclization of (XVIII) with 2-sulfanylethylamine (XIX) affords the thiazolidine (XX), which is dehydrogenated by means of MnO2 to provide the thiazole derivative (XXI). Finally, compound (XXI) is N-deprotected by a treatment with TFA to provide the 2-phenyl-1(S)-(2-thiazolyl)ethylamine intermediate (XXII).

合成路线6

Various new routes for the large-scale synthesis of Ro-31-8959 have been described: 1) The condensation of N-protected-L-phenylalanine (I) with the Mg salt of malonic acid monoethyl ester (II) gives the keto ester (III), which is enantioselectively reduced with NaBH4 to yield the hydroxy ester (IV). The reaction of (IV) with 2,2-dimethoxypropane (V) by means of p-toluenesulfonic acid affords the oxazolidine (VI), which is hydrolyzed with NaOH in ethanol/water to the corresponding acid (VII). The treatment of (VII) with oxalyl chloride, mercaptopyridine-N-oxide (MPO) and bromotrichloromethane affords the bromomethyloxazolidine (VIII), which, without isolation, is treated with acetic acid to give the N-protected 3(S)-amino-2-bromo-4-phenyl-2(S)-butanol (IX). The reaction of (IX) with KOH in methanol yields the epoxide (X), which is condensed with (3S,4aS,8aS)-N-tert-butyldecahydroisoquinoline-3-carboxamide (XI), yielding the protected condensation product (XII). The deprotection of the amino group of (XII) by hydrogenation with H2 over Pd/C affords the amino derivative (XIII), which is condensed with N-benzyloxycarbonyl-asparagine (XIV) in the usual way, giving the protected peptide (XV). The deprotection of (XV) as before yields compound (XVI), with a free amino group that is finally condensed with quinoline-2-carboxylic acid (XVII) by means of dicyclohexylcarbodiimide and hydroxybenzotriazole.

合成路线7

The condensation of resin bounded L-phenylalanine (I) with N-(tert-butoxycarbonyl)-L-phenylalanine (II) by means of 1,3-diisopropylcarbodiimide (DIC) and HOBT gives the protected, resin bounded dipeptide (III), which is deprotected with TFA to yield the dipeptide (IV). The reductocondensation of (IV) with 2-(tert-butoxycarbonyl)-1,2,3,4-tetrahydroisoquinoline-3-carbaldehyde (V) by means of NaBH3CN affords the protected pseudo tripeptide (VI), which is deprotected with TFA as before yielding the pseudo tripeptide (VII). The condensation of (VII) with the protected L-dimethyltyrosine (VIII) by means of DIC and HOBT affords the protected resin bounded seudotetrapeptide (IX), which is deprotected with TFA as before giving the resin bounded seudotetrapeptide (X). Finally, the target seudotetrapeptide is cleaved from the resin by means of HF and anisole.

合成路线8

The reaction of tert-butoxycarbonyl-L-phenylalanine (I) with isobutyl chloroformate in THF gives the expected mixed anhydride which is treated with diazomethane and HCl yielding the corresponding chloromethyl ketone (II). The reduction of (II) with NaBH4 in THF affords the (S)-chlorohydrin (IV), which is treated with KOH in ethanol to obtain the chiral epoxide (V)(1,2). Ring opening of (V) with (±)(cis)-N-tert-butyl-4-(4-pyridylmethoxy)piperidine-2-carboxamide (VI) by a treatment with LiCl in refluxing ethanol gives a mixture of diastereomers that is separated by chromatography giving the pure isomer (VII). The reaction of (VII) with tert-butoxycarbonyl-L-valine (VIII) by treatment first with trifluoroacetic acid (TFA), and condesation by means of BOP ((benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate) and NMM (N-methylmorpholine) affords the expected condensation product (IX). Finally, this compound is condensed with quinoline-2-carboxylic acid (X) by means of BOP and NMM as before. 2) The piperidine (VI) has been obtained by condensation of (±)(cis)-N-(tert-butoxycarbonyl)-4-hydroxypiperidine-2-carboxamide (XI) with 4-(chloromethyl)pyridine (XII) by means of NaH in DMS, followed by hydrolysis with HCl.

合成路线9

Compound (X) was submitted to successive coupling cycles (deprotection with TFA, and coupling with DIPCDI) to introduce sequentially the following amino acids: (XIb), (XIII) and (XV) yielding the following resins: (XII),(XIV) and (XVI), respectively.

合成路线10

Treatment of N-Boc-L-phenylalanine (XI) with carbonyl diimidazole, followed by condensation with the lithium enolate of ethyl acetate provided the beta-ketoester (XII). Then, reduction with NaBH4 in EtOH at -78 C furnished the anti aminoalcohol (XIII) as the major isomer. Subsequent reaction with formaldehyde in the presence of p-toluenesulfonic acid in boiling toluene produced the cis oxazolidine (XIV). Basic hydrolis of the ester group yielded carboxylic acid (XV) which, after activation as the mixed anhydride with 2,4,6-trichlorobenzoyl chloride (VI), was coupled to hydroxyester (X) to give triester (XVI). Reduction of the oxazolidine with NaBH3CN in the presence of trifluoroacetic acid afforded the N-methylated derivative (XVII). Then, hydrogenolysis of the benzyl ester in the presence of Pd/C produced acid (XVIII), which was finally cyclized using DPPA.

合成路线11

The intermediate (3R,4S)-4-[N-(tert-butoxycarbonyl)-N-methylamino]-5-phenyl-3-(tert-butyldimethylsilyloxy)pentanoic acid (VII) has been obtained as follows: The condensation of N-(tert-butoxycarbonyl)-L-phenylalanine (I) with the Mg salt of malonic acid monoethyl ester (II) by means of CDI gives the beta-ketoester (III), which is reduced with NaBH4 to yield (3R,4S)-4-(tert-butoxycarbonylamino)-3-hydroxy-5-phenylpentanoic acid ethyl ester (IV). The protection of the OH group of (IV) with Tbdms-Cl and imidazole in DMF affords the silylated ester (V), which is hydrolyzed with NaOH to provide the corresponding carboxylic acid (VI). Finally, this compound is N-methylated by means of Me-I and NaH in THF to obtain the target intermediate (VII).

合成路线12

Solid-phase peptide synthesis started with N-Boc-L-leucine linked to a PAM resin (VII). Deprotection of the Boc group was effected by treatment with trifluoroacetic acid in CH2Cl2 to give leucine-resin (VIII). Sequential couplings with the respective protected amino acids were mediated by DCC and HOBt, and trifluoroacetic acid in CH2Cl2 was used for deprotection of the Boc groups. The following protected amino acids were sequentially coupled: N-Boc-L-proline (IX), N-Boc-L-isoleucine (XI), N-Boc-L-proline (IX), N-Boc-L-glutamic acid omega-benzyl ester (XIV), N-Boc-L-phenylalanine (XVI) and N-Boc-L-aspartic acid omega-cyclohexyl ester (XVIII) to afford the peptide resins (X), (XII), (XIII), (XV), (XVII) and (XIX), respectively.

合成路线13

The condensation of 3-amino-1-(2-cyclohexyl-2-oxoethyl)-5-ethyl-9-methyl-2,3-dihydro-1H-1,4-benzodiazepin-2-one (I) with N-(tert-butoxycarbonyl)-L-phenylalanine (II) by means of HOBT and WSCD in DMF gives the corresponding amide as a diastereomeric mixture (IIIa-b), which is deprotected at the Boc group by treatment with HCl in ethyl acetate yielding the diastereomeric mixture of L-phenylalanine amides (IVa-b). The HPLC chromatographic separation of both diastereomers affords pure (Va) and (Vb). The desired diastereomer (Va) is treated with phenyl isothiocyanate (VI) to provide the chiral amine (R)-(VII), which is finally condensed with 3-methylphenyl isocyanate (VIII) to furnish the target urea.

合成路线14

Pinanediol leucine boronate (I) was coupled with N-Boc-L-phenylalanine (II) in the presence of TBTU to afford the dipeptide boronate (III). Acid cleavage of the Boc protecting group of (III), followed by acylation of the resultant amine (IV) with 2-pyrazinecarboxylic acid (V), furnished amide (VI). Finally, deprotection of the boronic acid (VI) was accomplished by two-phase transesterification with isobutylboronic acid.

合成路线15

The solid phase method for the synthesis of peptides is here used starting with a phenylacetamidomethyl resin coupled with boc-protected-L-leucine (I), which was coupled successively with protected L-2,3-diaminopropionic acid (II) yielding dipeptide (III), with protected L-phenylalanine (IV), yielding tripeptide (V), with protected L-tryptophan (VI) yielding tetrapeptide (VII), and with protected L-aspartic acid (VIII), yielding pentapeptide (IX). The cyclization of (IX) by selective deprotection of the side chains of diaminopropionic acid and aspartic acid with piperidine in DMF, followed by cyclization by means of PyBop and DIEA in DMF affords the cyclic pentapeptide (X).

合成路线16

Condensation of N-(tert-butoxycarbonyl)phenylalanine (I) with phenyllithium furnished ketone (II). The N-Boc group of (II) was deprotected with HCl in dioxan to yield aminoketone (III), which was then condensed with the succinate building block (IV) in DMF to afford succinamide (V). Further deprotection of the tert-butyl ester of (V) by treatment with trifluoroacetic acid provided carboxylic acid (VI), which was coupled with O-tert-butyldimethylsilyl hydroxylamine (VII) in the presence of EDC and HOBt to yield, after desilylation, the target hydroxamic acid.

合成路线17

The resin (X) was coupled with N-Boc-L-phenylalanine (XI) affording resin (XII). The acetylation of the free amino group, side-chain deprotection and cleavage from the resin (XII) employing liquid HF and p-cresol yielded the linear dipeptide (XIII). This was finally cyclized with benzotriazol-1-yloxytris (dimethylamino)phosphonium hexafluorophosphate (BOP) to produce the title cyclic peptide.

合成路线18

Condensation of Nalpha-Boc-Ndelta-Fmoc-Nalpha-methyl-L-ornithine (I) with beta-naphthylamine (II) to give the corresponding naphthyl amide (III) was effected by treatment with POCl3 and i-Pr2NEt. The Boc group of (III) was then deprotected by treatment with trifluoroacetic acid, yielding amine (IV). After activation of N-Boc-L-phenylalanine (V) as the mixed anhydride with ethyl chloroformate, coupling with amine (IV) afforded the protected dipeptide (VI). Deprotection of the Fmoc group of (VI) employing piperidine in dimethylacetamide gave (VII). Finally, Boc group cleavage in (VII) by treatment with trifluoroacetic acid furnished the title dipeptide amide.

合成路线19

Coupling of N-Boc-phenylalanine (I) with amine (II) by means of HBTU and DIEA provides amide (III), whose Boc group is removed by treatment with HCl in dioxane to afford amine hydrochloride (IV). Finally, the target compound is obtained by reductive amination between amine (IV) and aldehyde (V) in MeOH in the presence of NaCNBH3.

合成路线20

The title peptide was prepared by solid-phase synthesis using a p-methylbenzhydrylamine resin (II). Coupling of Boc-lysine(2-ClZ) (I) to the resin (II) using diisopropylcarbodiimide (DIC) and 1-hydroxybenzotriazole (HOBt) afforded the amide resin (III). The N-Boc group was then selectively deprotected with trifluoroacetic acid in CH2Cl2, yielding resin (IV). To this were sequentially attached the protected amino acids: Boc-phenylalanine (V), Boc-D-arginine(Ts) (VII) and Boc-2',6'-dimethyltyrosine(Boc) (IX) employing DIC/HOBt and then Boc deprotection with trifluoroacetic acid to provide the peptide resins (VI), (VIII) and (X), respectively. Finally, the desired peptide amide was deprotected and cleaved from the resin (X) by treatment with HF and anisole.

合成路线21

3-Iodo-L-tyrosine (I) was protected as the N-Boc derivative (II) and subsequently coupled to n-pentylamine yielding amide (III). Palladium-catalyzed carboxylation of the aryl iodide of (III) in the presence of MeOH afforded the methyl ester (IV). The phenolic hydroxyl group of (IV) was then alkylated with methyl bromoacetate under basic conditions to produce diester (V). Acidic Boc group cleavage in (V), followed by acylation of the resulting amine (VI) with N-Boc-L-phenylalanine (VII), generated the dipeptide derivative (VIII). Further deprotection of (VIII) with HCl in dioxane yielded amine (IX), which was finally coupled with succinic acid mono-methyl ester (X) to provide the title compound.

合成路线22

Coupling between N-Boc-O-benzyl-L-threonine (VII) and L-leucine benzyl ester (VIII) by means of DCC/HOBt gives the protected dipeptide (IX). Subsequent N-Boc group cleavage in (IX) upon treatment with formic acid yields (X). Further coupling of dipeptide (X) with N-Boc-L-phenylalanine (XI), followed by formic acid deprotection, leads to the benzyl-protected tripeptide (XII).

合成路线23

In a similar fashion, N-Boc-L-phenylalanine (XI) is coupled with L-valine benzyl ester (XIII) to furnish the protected dipeptide (XIV). Debenzylation of (XIV) with H2 and Pd/C leads to acid (XV), which is then condensed with tripeptide (XII) to yield, after deprotection with formic acid, the pentapeptide derivative (XVI).

合成路线24

合成路线25

Condensation of N-Boc-L-leucine (X) with L-phenylalanine methyl ester (XI) in the presence of DIEA, HOBt and BOP in DMF gives the protected dipeptide (XII). Dipeptide (XII) is then deprotected by means of TFA in CH2Cl2 to yield L-Leu-L-Phe-OMe trifluoroacetate salt (XIII), which without isolation is then condensed with N-Boc-Lhomophenylalanine (XIV) in the presence of DIEA, HOBt and BOP in acetonitrile to yield the protected tripeptide (XV) . Then, N-deprotection of peptide (XV) by means of TFA in CH2Cl2 gives tripeptide (XVI), which is finally coupled with chloroacetyl chloride (XVII) in the presence of DIEA in DMF .

合成路线26

The tripeptide benzyl ester precursor (IV) is prepared by the following procedure. Condensation of N-Boc-L-leucine (X) with L-phenylalanine benzyl ester (XVIII) in the presence of DIEA, HOBt and PyBOP in acetonitrile gives the protected dipeptide (XIX), which upon deprotection by means of TFA in CH2Cl2 yields dipeptide (XX). Without isolation, intermediate (XX) is then condensed with N-Boc-L-homophenylalanine (XIV) in the presence of DEEA (diethyl-aminoethanol), HOBt and PyBOP in acetonitrile to provide protected tripeptide (XXI) , which is finally N-deprotected by means of TFA in CH2Cl2 .