N-[(Phenylmethoxy)carbonyl]-L-tyrosine methyl ester

To the above-obtained solid Tyr-OMe · HCl (tyrosine hydrochloride), 300 g of AcOEt (ethyl acetate) was added, 100 g of Na2CO3 (sodium carbonate) was added with stirring, 50 g of water was added, And 230 g of Z-Cl (benzyl chloroformate) was slowly added dropwise.Control system pH = 8, by TLC (thin layer chromatography) to the reaction system without Tyr-OMe · HCl (tyrosine hydrochloride), after adding citric acid, acidified to pH = 3, static layer , The ester layer was washed with salt water as neutral.The ester layer was added with 20 ~ 50g anhydrous Na2SO4 (anhydrous sodium sulfate), stirred and dried for 4 hours. Na2SO4 (sodium sulfate) was removed by filtration. The filtrate was concentrated and then added to a crystallization kettle. The hot water was concentrated to dryness.Add PET (petroleum ether) 200g, stirring crystallization is completed.The white crystals of the white crystals Z-L-Tyr-OMe (N-benzyloxycarbonyl-L-tyrosine methyl ester) were filtered and dried to dryness to dryness of 390 g and water at 4percent.3.. To a solution of N-Cbz-L-tyrosine (10.0 g, 31.7 mmol) in 100 mL of anhydrous MeOH was added 1 mL of concentrated sulfuric acid and the resulting mixture was heated at reflux overnight. The solution was then cooled to room temperature and concentrated under reduced pressure. The residue was diluted in 30 mL Et2O was added and washed successively with 5percent aqueous NaHCO3, brine, and finally dried over MgSO4. After drying under vacuum 5 was obtained as a pale yellow resin (9.0 g, 86 percent). 1H NMR (500 MHz, CDCl3) δ 7.35 (m, 5H), 6.96 (d, J = 8.2 Hz, 2H), 6.72 (d, J = 8.2 Hz, 2H), 5.69 (bs, 1H; OH), 5.29 (d, J = 8.2 Hz, 1H; NH), 5.14 (d, JAB = 12.2, 1H), 5.10 (d, JAB = 12.2, 1H), 4.65 (m, 1H), 3.75 (s, 3H), 3.08 (dd, J = 5.5 Hz, JAB = 14.0 Hz, 1H), 3.02 (dd, J = 5.5 Hz, JAB = 14.0 Hz, 1H). 13C NMR (127 MHz, CDCl3) δ 172.3, 155.8, 155.0, 136.1, 130.4, 128.6, 128.3, 128.1, 127.4, 115.6, 67.1, 55.0, 52.4, 37.5.

Molecular Weight:329.3
XLogP3:2.2
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:5
Rotatable Bond Count:8
Exact Mass:329.12632271
Monoisotopic Mass:329.12632271
Topological Polar Surface Area:84.9
Heavy Atom Count:24
Complexity:400
Defined Atom Stereocenter Count:1
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes