benzyl N-[(2S)-1-amino-1-oxo-3-phenylpropan-2-yl]carbamate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 6.55 g (22 mmoles) of Z--Phe--NH2, prepared as described in Example 1, Step 1, are dissolved in 13 ml of acetic acid, and 30 ml of 5 n hydrogen bromide in acetic acid are added to the solution. After 5 minutes of stirring a thick precipitate separates. The suspension is allowed to stand for one hour, thereafter it is diluted with dry ether and filtered. The crude product is dissolved in 240 ml of ethanol, the solution is decolorized, and the product is precipitated with 740 ml of ether. 4.90 g (91 %) of H--Phe--NH2.HBr are obtained; the white, crystalline substance is chromatographically uniform. (Two spots appear on the thin layer chromatogram: one of them belongs to the product and the other to hydrogen bromide). M.P.: 249-250° C., Rf8 : 0.50; Rf8,HBr: 0.35. to stand for one hour filtered The crude product is dissolved in 240 ml of ethanol the product is precipitated with 740 ml of ether 4.90 g (91 %) of H--Phe--NH2.HBr are obtained

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: An 18 g portion of Nα -[(phenylmethoxy)carbonyl]-L-phenylalanine and 6.6 ml of N-methylmorpholine were dissolved in 150 ml of tetrahydrofuran and stirred at 31 10° C. as 8.04 ml of isobutylchloroformate was added. After 1 minute, ammonia gas was bubbled through the mixture until it was saturated. The mixture was stirred an additional 30 minutes and then poured into ice-water. The white solid was collected, giving 16.76 g of the desired compound, mp 164°-165° C. was added ammonia gas was bubbled through the mixture until it poured into ice-water The white solid was collected

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Cbz-Phe-NH2 (4.86 g, 16.29 mmoles) was dissolved in DMF under nitrogen and cooled on ice bath. Cyanuric chloride (1.95 g, 10.59 mmoles) was added with stirring, and the mixture was allowed to warm to rt overnight. Water (100 ml) and ethyl acetate (250 ml) were added to the mixture. The organic phase was separated and washed three times with water (100 ml) and then dried over magnesium sulfate. The material was filtered and concentrated in vacuo to afford Cbz-Phe-CN as a white solid (4.56 g, 99%) HPLC analysis: >99% purity; Retention time 10.1 min. cooled on ice bath The organic phase was separated washed three times with water (100 ml) dried over magnesium sulfate The material was filtered concentrated in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 6.55 g (22 mmoles) of Z--Phe--NH2, prepared as described in Example 1, Step 1, are dissolved in 13 ml of acetic acid, and 30 ml of 5 n hydrogen bromide in acetic acid are added to the solution. After 5 minutes of stirring a thick precipitate separates. The suspension is allowed to stand for one hour, thereafter it is diluted with dry ether and filtered. The crude product is dissolved in 240 ml of ethanol, the solution is decolorized, and the product is precipitated with 740 ml of ether. 4.90 g (91 %) of H--Phe--NH2.HBr are obtained; the white, crystalline substance is chromatographically uniform. (Two spots appear on the thin layer chromatogram: one of them belongs to the product and the other to hydrogen bromide). M.P.: 249-250° C., Rf8 : 0.50; Rf8,HBr: 0.35. to stand for one hour filtered The crude product is dissolved in 240 ml of ethanol the product is precipitated with 740 ml of ether 4.90 g (91 %) of H--Phe--NH2.HBr are obtained

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In 30 mL of MeCN, 5.99 g of Z-Phe was dissolved and 3.94 g of HONB and 4.59 g of WSCD HCl were added to the solution at 0° C., followed by stirring at room temperature for 4 hours. While keeping at 0° C., 3.4 mL of 25% NH3 aq. solution and 10 mL of DMF were added to the mixture, followed by stirring for 4 hours. After the solvent was distilled off, the residue was dissolved in AcOEt and the solution washed with 1N HCl aq. solution, satd. NaHCO3 aq. solution and then satd. NaCl aq. solution. After drying over Na2SO4, the solvent was concentrated and diethyl ether was added to give 1.48 g (yield 99%) of Z-Phe-NH2 as the precipitate. After 1.94 g of [Bis(trifluoroacetoxy)iodo]benzene was dissolved in 20 mL of MeCN and 5 mL of H2O, 890 mg of Z-Phe-NH2 prepared above and 972 μL of pyridine were added to the precipitate at 0° C., followed by stirring at room temperature for 15 hours. After the solvent was concentrated, the concentrate was subjected to liquid-liquid separation with diethyl ether-1N HCl aq. solution and the 1N HCl aq. solution layer was concentrated and then dried. Its half volume was dissolved in 5 mL of DMF, and 486 μL of mono-tert-butyl malonate and 540 mg of HOBt were added to the solution. Then, 2.08 g of PyBOP and 1394 μL of DIEA were added at 0° C. to the mixture, followed by stirring at room temperature for 15 hours. After the solvent was distilled off, the residue was dissolved in AcOEt and the solution washed with 1N HCl aq. solution, satd. NaHCO3 aq. solution and then satd. NaCl aq. solution. After drying over Na2SO4, the solvent was concentrated and the concentrate was purified by flash column chromatography. Diethyl ether-petroleum ether was added to give 304 mg (yield 33%) of Z-PheΨ(NHCO)Gly-OBut as the precipitate. After 154 mg of the product was dissolved in 20 ml of MeOH, 10% Pd—C was added to the solution, followed by catalytic hydrogenation for 2 hours in a hydrogen flow. After removal of the catalyst by filtration, the solvent was concentrated and dried. The residue was dissolved in 10 mL of MeCN 10 mL and 152 mg of Fmoc-OSu and 78 μL of DIEA were added to the solution, followed by stirring for 15 hours. After the solvent was distilled off, the residue was dissolved in AcOEt and the solution washed with 1N HCl aq. solution, satd. NaHCO3 aq. solution and then satd. NaCl aq. solution. After drying over Na2SO4, the solvent was concentrated and diethyl ether-petroleum ether was added to give 127 mg (yield 68%) of Fmoc-PheΨ(NHCO)Gly-OBut as the precipitate. Fmoc-Leu was introduced into 63 mg of Fmoc-Arg(Boc2,Me)Phe-Rink Amide MBHA resin prepared in EXAMPLE 10. After Fmoc deprotection, Fmoc-PheΨ(NHCO)Gly-OH (prepared by treating 25 mg of Fmoc-PheΨ(NHCO)Gly-OBut with TFA for 3 minutes), 300 μL of 0.5M HOAt, 78 mg of PyAOP and 52 μL of DIEA were added to the resin, followed by shaking for 6 hours. After the resin washed, 2 mL of DMF, 9 μL of DIEA and 12 μL of Ac2O were added to the resin, followed by shaking for 30 minutes. After the resin washed, the peptide chain was extended on ABI 433A to give Boc-D-Tyr(But)Asn(Trt)Trp(Boc)Asn(Trt)Ser(But)PheΨ(NHCO)GlyLeuArg(Boc2,Me)Phe-Rink Amide MBHA resin. To 34 mg of the product, 200 μL of TFA/PhSMe/m-cresol/TIS/EDT (85/5/5/2.5/2.5) was added, followed by stirring for 2 hours. Ether was added to the reaction solution, the resulting precipitate was centrifuged and the supernatant was removed. This procedure was repeated for washing. The residue was extracted with an aqueous acetic acid solution and the extract was filtered to remove the resin. Then, linear density gradient elution (30 minutes) was performed with eluants A/B: 76/24-66/34 using: 0.1% TFA in water and eluant B: 0.1% TFA-containing acetonitrile on preparative HPLC using YMC D-ODS-5-ST S-5 120A column (20×150 mm). The fractions containing the product were collected and lyophilized to give 0.7 mg of white powders. While keeping at 0° C. by stirring for 4 hours After the solvent was distilled off the residue was dissolved in AcOEt the solution washed with 1N HCl aq. solution After drying over Na2SO4 the solvent was concentrated diethyl ether was added

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In 30 mL of MeCN, 5.99 g of Z-Phe was dissolved, and 3.94 g of HONB and 4.59 g of WSCD HCl were added to the solution at 0° C., followed by stirring at room temperature for 4 hours. While keeping at 0° C., 3.4 mL of 25% NH3 aq. solution and 10 mL of DMF were added to the mixture, followed by stirring for 4 hours. After the solvent was distilled off, the residue was dissolved in AcOEt and the solution was washed with 1N HCl aq. solution, satd. NaHCO3 aq. solution and then satd. NaCl aq. solution. After drying over Na2SO4, the solvent was concentrated and diethyl ether was added to give 1.48 g of Z-Phe-NH2 as precipitates (yield 99%). After 1.94 g of [Bis(trifluoroacetoxy)iodo]benzene was dissolved in 20 mL of MeCN and 5 mL of H2O, 890 mg of Z-Phe-NH2 prepared above and 972 μL of pyridine were added to the precipitate at 0° C., and the mixture was stirred at room temperature for 15 hours. After the solvent was concentrated, the concentrate was subjected to liquid-liquid separation with diethyl ether-1N HCl aq. solution. The 1N HCl aq. solution layer was concentrated and then dried. A half volume of the concentrate was dissolved in 5 mL of DMF, and 486 μL of mono-tert-butyl malonate and 540 mg of HOBt were added to the solution. Then, 2.08 g of PyBOP and 1394 μL of DIEA were added to the mixture at 0° C., followed by stirring at room temperature for 15 hours. The solvent was distilled off, the residue was dissolved in AcOEt and the solution was washed with 1N HCl aq. solution, satd. NaHCO3 aq. solution and then satd. NaCl aq. solution. After drying over Na2SO4, the solvent was concentrated and the concentrate was purified by flush column chromatography. Diethyl ether-petroleum ether was added to give 304 mg (yield 33%) of Z-PheΨ(NHCO)Gly-OBut as precipitates. After 154 mg of the product was dissolved in 20 mL of MeOH, 10% Pd—C was added to the solution, followed by catalytic hydrogenation for 2 hours in a hydrogen flow. After removal of the catalyst by filtration, the solvent was concentrated and dried. The residue was dissolved in 10 mL of MeCN 10 mL and 152 mg of Fmoc-OSu and 78 μL of DIEA were added to the solution, followed by stirring for 15 hours. After the solvent was distilled off, the residue was dissolved in AcOEt and the solution was washed with 1N HCl aq. solution, satd. NaHCO3 aq. solution and then satd. NaCl aq. solution. After drying over Na2SO4, the solvent was concentrated and diethyl ether-petroleum ether was added to give 127 mg of Fmoc-PheΨ(NHCO)Gly-OBut as precipitates (yield 68%). Fmoc-Leu was introduced into 63 mg of Fmoc-Arg(Boc2,Me)Phe-Rink Amide MBHA resin prepared in EXAMPLE 10. Following Fmoc deprotection, Fmoc-PheΨ(NHCO)Gly-OH (prepared by treating 25 mg of Fmoc-PheΨ(NHCO)Gly-OBut with TFA for 3 minutes), 300 μL of 0.5M HOAt, 78 mg of PyAOP and 52 μL of DIEA were added to the resin, and the mixture was shaken for 6 hours. After washing the resin, 2 mL of DMF, 9 μL of DIEA and 12 μL of Ac2O were added to the resin, and the mixture was shaken for 30 minutes. After washing the resin, the peptide chain was extended on ABI 433A to give Boc-D-Tyr(But)Asn(Trt)Trp(Boc)Asn(Trt)Ser(But)Phe‥(NHCO)GlyLeuArg(Boc2 μM e)Phe-Rink Amide MBHA resin. To 34 mg of the product, 200 μL of TFA/PhSMe/m-cresol/TIS/EDT (85/5/5/2.5/2.5) was added, and the mixture was stirred for 2 hours. Ether was added to the reaction solution. The resulting precipitate was centrifuged and the supernatant was removed. This procedure was repeated for washing. The residue was extracted with an aqueous acetic acid solution and the extract was filtered to remove the resin. Linear density gradient elution (60 minutes) was then performed with eluants A/B:76/24-66/34 using: 0.1% TFA in water and eluant B: 0.1% TFA-containing acetonitrile on preparative HPLC using YMC D-ODS-5-ST S-5 120A column (20×150 mm). The fractions containing the product were collected and lyophilized to give 0.7 mg of white powders. While keeping at 0° C. by stirring for 4 hours After the solvent was distilled off the residue was dissolved in AcOEt the solution was washed with 1N HCl aq. solution After drying over Na2SO4 the solvent was concentrated diethyl ether was added

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In 30 mL of MeCN, 5.99 g of Z-Phe was dissolved and 3.94 g of HONB and 4.59 g of WSCD HCl were added to the solution at 0° C., followed by stirring at room temperature for 4 hours. While keeping at 0° C., 3.4 mL of 25% NH3 aq. solution and 10 mL of DMF were added to the mixture, followed by stirring for 4 hours. After the solvent was distilled off, the residue was dissolved in AcOEt and the solution washed with 1N HCl aq. solution, satd. NaHCO3 aq. solution and then satd. NaCl aq. solution. After drying over Na2SO4, the solvent was concentrated and diethyl ether was added to give 1.48 g (yield 99%) of Z-Phe-NH2 as the precipitate. After 1.94 g of [Bis(trifluoroacetoxy)iodo]benzene was dissolved in 20 mL of MeCN and 5 mL of H2O, 890 mg of Z-Phe-NH2 prepared above and 972 μL of pyridine were added to the precipitate at 0° C., followed by stirring at room temperature for 15 hours. After the solvent was concentrated, the concentrate was subjected to liquid-liquid separation with diethyl ether-1N HCl aq. solution and the 1N HCl aq. solution layer was concentrated and then dried. Its half volume was dissolved in 5 mL of DMF, and 486 μL of mono-tert-butyl malonate and 540 mg of HOBt were added to the solution. Then, 2.08 g of PyBOP and 1394 μL of DIEA were added at 0° C. to the mixture, followed by stirring at room temperature for 15 hours. After the solvent was distilled off, the residue was dissolved in AcOEt and the solution washed with 1N HCl aq. solution, satd. NaHCO3 aq. solution and then satd. NaCl aq. solution. After drying over Na2SO4, the solvent was concentrated and the concentrate was purified by flush column chromatography. Diethyl ether-petroleum ether was added to give 304 mg (yield 33%) of Z-PheΨ(NHCO)Gly-OBut as the precipitate. After 154 mg of the product was dissolved in 20 mL of MeOH, 10% Pd—C was added to the solution, followed by catalytic hydrogenation for 2 hours in a hydrogen flow. After removal of the catalyst by filtration, the solvent was concentrated and dried. The residue was dissolved in 10 mL of MeCN 10 mL and 152 mg of Fmoc-OSu and 78 μL of DIEA were added to the solution, followed by stirring for 15 hours. After the solvent was distilled off, the residue was dissolved in AcOEt and the solution washed with 1N HCl aq. solution, satd. NaHCO3 aq. solution and then satd. NaCl aq. solution. After drying over Na2SO4, the solvent was concentrated and diethyl ether-petroleum ether was added to give 127 mg (yield 68%) of Fmoc-PheΨ(NHCO)Gly-OBut as the precipitate. Fmoc-Leu was introduced into 63 mg of Fmoc-Arg(Boc2,Me)Phe-Rink Amide MBHA resin prepared in EXAMPLE 10. After Fmoc deprotection, Fmoc-PheΨ(NHCO)Gly-OH (prepared by treating 25 mg of Fmoc-PheΨ(NHCO)Gly-OBut with TFA for 3 minutes), 300 μL of 0.5M HOAt, 78 mg of PyAOP and 52 μL of DIEA were added to the resin, followed by shaking for 6 hours. After the resin washed, 2 mL of DMF, 9 μL of DIEA and 12 μL of Ac2O were added to the resin, followed by shaking for 30 minutes. After the resin washed, the peptide chain was extended on ABI 433A to give Boc-D-Tyr(But)Asn(Trt)Trp(Boc)Asn(Trt)Ser(But)PheΨ(NHCO)GlyLeuArg(Boc2,Me)Phe-Rink Amide MBHA resin. To 34 mg of the product, 200 μL of TFA/PhSMe/m-cresol/TIS/EDT (85/5/5/2.5/2.5) was added, followed by stirring for 2 hours. Ether was added to the reaction solution, the resulting precipitate was centrifuged and the supernatant was removed. This procedure was repeated for washing. The residue was extracted with an aqueous acetic acid solution and the extract was filtered to remove the resin. Then, linear density gradient elution (30 minutes) was performed with eluants A/B: 76/24-66/34 using: 0.1% TFA in water and eluant B: 0.1% TFA-containing acetonitrile on preparative HPLC using YMC D-ODS-5-ST S-5 120A column (20×150 mm). The fractions containing the product were collected and lyophilized to give 0.7 mg of white powders. While keeping at 0° C. by stirring for 4 hours After the solvent was distilled off the residue was dissolved in AcOEt the solution washed with 1N HCl aq. solution After drying over Na2SO4 the solvent was concentrated diethyl ether was added

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: An 18 g portion of Nα -[(phenylmethoxy)carbonyl]-L-phenylalanine and 6.6 ml of N-methylmorpholine were dissolved in 150 ml of tetrahydrofuran and stirred at 31 10° C. as 8.04 ml of isobutylchloroformate was added. After 1 minute, ammonia gas was bubbled through the mixture until it was saturated. The mixture was stirred an additional 30 minutes and then poured into ice-water. The white solid was collected, giving 16.76 g of the desired compound, mp 164°-165° C. was added ammonia gas was bubbled through the mixture until it poured into ice-water The white solid was collected

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Cbz-Phe-NH2 (4.86 g, 16.29 mmoles) was dissolved in DMF under nitrogen and cooled on ice bath. Cyanuric chloride (1.95 g, 10.59 mmoles) was added with stirring, and the mixture was allowed to warm to rt overnight. Water (100 ml) and ethyl acetate (250 ml) were added to the mixture. The organic phase was separated and washed three times with water (100 ml) and then dried over magnesium sulfate. The material was filtered and concentrated in vacuo to afford Cbz-Phe-CN as a white solid (4.56 g, 99%) HPLC analysis: >99% purity; Retention time 10.1 min. cooled on ice bath The organic phase was separated washed three times with water (100 ml) dried over magnesium sulfate The material was filtered concentrated in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 6.55 g (22 mmoles) of Z--Phe--NH2, prepared as described in Example 1, Step 1, are dissolved in 13 ml of acetic acid, and 30 ml of 5 n hydrogen bromide in acetic acid are added to the solution. After 5 minutes of stirring a thick precipitate separates. The suspension is allowed to stand for one hour, thereafter it is diluted with dry ether and filtered. The crude product is dissolved in 240 ml of ethanol, the solution is decolorized, and the product is precipitated with 740 ml of ether. 4.90 g (91 %) of H--Phe--NH2.HBr are obtained; the white, crystalline substance is chromatographically uniform. (Two spots appear on the thin layer chromatogram: one of them belongs to the product and the other to hydrogen bromide). M.P.: 249-250° C., Rf8 : 0.50; Rf8,HBr: 0.35. to stand for one hour filtered The crude product is dissolved in 240 ml of ethanol the product is precipitated with 740 ml of ether 4.90 g (91 %) of H--Phe--NH2.HBr are obtained