* All experimental methods are cited from the reference, please refer to the original source for details. We do not guarantee the accuracy of the content in the reference.
With phosgene In tetrahydrofuran at 45 - 65℃; for 1.08333 h;
EXAMPLE 2: PREPARATION OF L-GLUTAMIC ACID N-CARBOXYANHYDRIDE, y-BENZYL ESTER.; [0031] In this Example, a stirred mixture of 3.3 liters anhydrous tetrahydrofuran and 466 g (1.96 moles) L-glutamic acid, γ-benzyl ester, was purged with nitrogen below liquid surface at 0.5 liters/min and heated to 45°C over 30 minutes. The nitrogen purge was increased to 2 liters/min and 389 g (3.93 moles) gaseous phosgene was added at a rate to maintain a reaction mixture temperature of 50°-65°C over 10 minutes. The phosgene was refluxed back into the reaction vessel using a dry ice/acetone reflux condenser. After the phosgene was added, the reaction mixture was heated at 50°-65°C for 25 minutes until the solids disappeared and a clear solution resulted. The dry ice and acetone were removed from the reflux condenser and the reaction mixture was purged with nitrogen at 4 liters/min and 50°-65°C for 30 minutes. The tetrahydrofuran and excess phosgene were removed by vacuum stripping at50°-65°C down to 15 mm Hg whereupon the concentrated residue crystallized. EPO <DP n="15"/>The stripped residue was dissolved in 2.8 liters anhydrous ethyl acetate and the cloudy mixture vacuum filtered to remove insoluble solids. Anhydrous hexanes (5.5 liters) were added gradually with stirring to the filtrate to crystallize the product. The product slurry was stirred for 30 minutes and refrigerated at 5°C overnight. The product was isolated by vacuum filtration under a nitrogen blanket, washed with a 0.93 liter solution of 3:1 , hexanes.ethyl acetate and with 1.4 liters hexanes, dried in the funnel by pulling vacuum on it for 30 minutes while maintaining a positive nitrogen purge and vacuum dried at room temperature to a constant weight. After drying, 461 g (89.2percent yield) L-glutamic acid N-carboxyanhydride, γ-benzyl ester were produced with a melting point of92°-94°C and a chloride content of 0.022percent.
Reference：
[1] Patent: WO2006/47703, 2006, A2, . Location in patent: Page/Page column 12-13
[2] Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999), 1982, p. 1317 - 1324
[3] Journal of the Chemical Society, 1950, p. 3239,3243
[4] Biomacromolecules, 2011, vol. 12, # 10, p. 3797 - 3804
2
[ 1676-73-9 ]
[ 503-38-8 ]
[ 3190-71-4 ]
Yield
Reaction Conditions
Operation in experiment
95%
at 70℃; Inert atmosphere
The synthesis was similar to the synthesis of N-ε-benzyloxycarbonyl-L-lysine-N-carboxyanhydride. 10.01 g (42.1 mmol) of benzyl-ester protected glutamine and 200 mL of abs. THF were used and 4.07 mL (33.7 mmol) of diphosgene were added. 10.52 g of the purified product (40 mmol; 95percent yield; colorless needles; melting point: 93–94 °C (lit: 93–94 °C [38])) were obtained and stored in a Schlenk tube at −80 °C. 1H NMR (300 MHz, CDCl3): δ [ppm]=9.11 (1H, s, –NH–), 7.42–7.20 (5H, m, C6H5), 5.10 (2H, s, –CH2– C6H5), 4.47 (1H, dd (3JH,H=7.9, 5.5Hz), –CO–CH–NH–), 2.50 (2H, t (3JH,H=7.9Hz), BnO–CO–CH2–), 2.15–1.85 (2H, m, –CH2–CH–).
93.7%
at 20℃; for 4 h;
General procedure: A two-necked, round-bottomed flask was charged with the requisite amino acid (1 eq.) and dried under high vacuum at ∼30–40 mTorr for >36 h to remove as much residual moisture as possible. The reaction flask was equipped with a reflux condenser topped with a dual-connection glass adapter, with one end connected to a nitrogen source and the other vented to the top of the fume hood (to properly exhaust the HCl vapors generated). Depending on the reaction scale, either a magnetic stir bar or mechanical paddle stirrer was inserted. Anhydrous THF was added to give an amino acid concentration of 0.4–0.5 M. To the resulting heavy suspension was added neat diphosgene (0.6–1.0 eq.; see Tables 2 and 4) in one portion. The reaction was carefully warmed to 55 °C with an oil bath or left to stir at ambient temperature. The reaction was considered complete when all the solids in the reaction dissolved and 1H NMR analysis of a vacuum-dried 0.3-mL aliquot indicated complete conversion to the product. Once at ambient temperature, the reaction mixture was transferred to a clean and dry round-bottomed flask, and concentrated on a rotary evaporator with the water bath maintained between 25 and 30 °C. Fresh anhydrous THF (∼6–8 mL/g of amino acid) was added to dissolve the material before reconcentrating. The crude product was dissolved in a minimal amount of THF (∼4–6 mL/g of amino acid) and transferred to a large precipitation container. Under a blanket of nitrogen, with vigorous mechanical stirring, heptane (6–8 crude volume) was added over 10–30 min to precipitate. The resulting solid was collected by vacuum filtration, washed with additional heptane (1–2 crude volume), and dried in a vacuum oven at room temperature overnight. Anhydrous DCM (∼8–10 mL/g NCA) was added to the material and stirred for 15–30 min under nitrogen in order to dissolve as much of the crude material as possible. Oven-dried celite with a bed height of 2–4 cm was prepared in a sintered glass Buchner funnel, topped with a Whatman glass microfiber filter, and rinsed with anhydrous DCM before use (taking care to avoid cracks in the bed). The DCM-NCA suspension was filtered through the celite bed and then rinsed through with additional anhydrous DCM (3–5 mL/g of NCA). The clear filtrate was concentrated on a rotary evaporator with the water bath maintained at 25–30 °C. Anhydrous THF (∼6–8 mL/g of NCA) was added to dissolve the product before reconcentrating. The material was dissolved in a minimal amount of THF (∼4–6 mL/g of NCA), precipitated with heptane (6–8 crude volume), and collected/dried using the same method as described for the first precipitation. The final product was packaged under either nitrogen or argon in a container that was then sealed in a FoodSaver heat-seal vacuum bag and stored at 78 °C until use.
80%
With limonene. In tetrahydrofuran at 60℃; for 2 h; Inert atmosphere
H-L-Glu(OBzI)-OH (17 g, 71.66 mmol) was added to a two-neck 250 mE round bottom flask fitted with a stirrer bar, reflux column, dropping funnel and an argon in and outlet. The apparatus was purged with Ar for 5 mm. Afterwards THF (120 mE, anhydrous) was added and the contents were heated to 60°C. Limonene (11.6 mE, 71.66 mmol, 1 Eq) was added to the stirring suspension before diphosgene (5.2 mE, 8.5 g, 43 mmol, 0.6 Eq) dissolved in THF (10 mE, anhydrous) was added via a dropping funnel over a period of 10 mm. The reaction was left stirring for 2 hours at 60° C. whilst purging with Ar leading to a clear solution. The reacH tion mixture was bubbled with Ar to aid the removal of remaining HC1 for 2 hours whilst the Ar outlet was directed through an aqueous 1M sodium hydroxide solution to neutralize the gas. The reaction solvent was reduced to a quarter of the original volume by rotary evaporation and ethyl acetate (32 mE) was added. The contents were added to ice cold hexane (200 mE) to form a white precipitate, which was isolated by vacuum filtration and washed with cold hexane. 10066] The solid was recrystallized from toluene (50 mE, anhydrous) and THF (30 mE, anhydrous) under inert atmosphere (N2 or Ar) by using a 250 mE two neck-flask 250 round bottom flask fitted with a stirrer bar, reflux column and an argon inlet and outlet where crystallization was induced by a dropwise addition of cold hexane (27 mE). The solution was stored for one hour at 4° C., and then at —20° C. overnight. Finally the white crystals were filtered underAr conditions by using schlenck techniques, and stored at —20° C.10067] To ensure that residual HC1 had been successfully removed, NCA (2-4 mg) was dissolved in THF (0.5 mE) and added to a 1M silver nitrate solution (1 mE) where the solution remained cleat When the Ag+ and Cl— ions meet they form the colorless insoluble AgCI salt, which can be easily detected. Another test is checking the solubility in THF. The NCA is soluble in THF, if turbidity is seen in the solution, can be due to the presence of remaining hexane and should disappear by heating the solution, but if precipitation is seen is due to the presence of polymer or starting material (both not soluble in THF).10068] Yields: 70-80percent. Melting point: 93.4° C. Molecular formula: C,3H,3N05. l3enzyl 3-(2,5-dioxooxazol-4-il)pro- panoate Molecular Weight: 263.25 gmol ‘H NMR (300 MHz, CDC13) ö 7.29 (m, 5H), 6.84 (s, 1H), 5.07 (s, 2H), 4.32 (t, J=6.2 Hz, 1H), 2.52 (t, J=7.0 Hz, 2H), 2.31-1.94 (m, 2H). ‘H -NRM spectra of pure final product is shown in FIG. 1.
Reference：
[1] Biomacromolecules, 2014, vol. 15, # 2, p. 548 - 557
[2] Macromolecular Bioscience, 2015, vol. 15, # 1, p. 63 - 73
[3] Polymer, 2015, vol. 67, p. 240 - 248
[4] Synthetic Communications, 2017, vol. 47, # 1, p. 53 - 61
[5] Journal of Organic Chemistry, 1985, vol. 50, # 5, p. 715 - 716
[6] Patent: US2015/87788, 2015, A1, . Location in patent: Paragraph 0059; 0065; 0066; 0067; 0068;
[7] Bulletin of the Chemical Society of Japan, 1994, vol. 67, # 3, p. 742 - 747
3
[ 32315-10-9 ]
[ 1676-73-9 ]
[ 3190-71-4 ]
Yield
Reaction Conditions
Operation in experiment
89%
at 55℃; for 1.5 h; Inert atmosphere
A 250 mL flame-dried round-bottom flask was charged with BGlu (6.2 g, 26 mmol) and triphosgene (3.7 g, 13 mmol) under argon. Then, dry THF (130 mL) was added and the reaction mixture was stirred at 55 °C for 90 min. The clear reaction mixture was then concentrated under vacuum followed by precipitation in hexane. The product was crystallized three times from THF/hexane. Yield: 6.1 g (89percent).
78%
at 50℃; for 4 h; Inert atmosphere; Large scale
Example 1 SYNTHESIS OF (5-BENZYL ESTER GLUTAMIC ACID-N-CARBOXYANHYDRIDE) (NCA-ESTER) To a 100 L Rot-evaporate system, γ-benzyl-L-glutamate (3.0 kg) and anhydrous THF (30 L) were added. The mixture was stirred for 10 minutes under a nitrogen atmosphere. Triphosgene (1.5 kg) was added in one portion, and the mixture was stirred for 4 hours at 50° C. under a nitrogen atmosphere. The stirring was then stopped and the mixture was cooled to room temperature. N-hexane (50 L) was added with stirring. After addition was complete, the mixture stirred for 30 minutes, and the resulting suspension was stored at −20° C. for 24 hours. The product was isolated as a white precipitate by filtration. The product was then washed with n-hexane to remove excess triphosgene. The product was recrystallized from acetate and n-hexane to provide the NCA-ester (2.6 kg, yield 78percent). 1H NMR (400 MHz, CDCl3) δ: 2.11 (m, 1H), 2.13 (m, 1H), 2.58 (m, 2H), 4.36 (m, 1H), 5.12 (s, 2H), 6.61 (s, 1H), 7.35 (m, 5H).
68.7%
at 50℃; Inert atmosphere
γ-Benzyl-L-glutamate BLG (20 g, 84.3 mmol) was suspendedin anhydrous THF (200 mL) at 50 °C and stirredunder N2. Triphosgene (8.88 g, 30 mmol) was then added.After the reaction solution became clear, the reaction solutionwas cooled and then precipitated in n-hexane (500 mL).The mixture was filtered and recrystallization in THF/hexane.14.6 g BLG-NCA was obtained. Yield: 68.7percent. Tyr-NCA was synthesized by reacting L-tyrosine with triphosgenein dry THF in N2 atmosphere in a similar way.Yield: 76.4percent.
35%
at 50℃; for 1 h; Inert atmosphere
y-Benzyl-L-glutamate N-carboxyanhydride (NCA). L-Glutamic acid y-benzyl ester (13.7 g, 57.8mmol) was added to a dry round bottomed flask. Anhydrous THF (200 mL) and triphosgene (6.8g, 23.0 mmol) were then added under nitrogen atmosphere. The mixture heated at 502C under stirring. The reaction mixture turned clear in about lh. The solution was then cooled down to room temperature and flushed with nitrogen 2h to remove traces of gaseous co-products in solution. The solution was then concentrated under reduced pressure to a final volume ofapproximately 10 mL and added to 100 mL of petroleum ether. The resulting solid was filtered, washed with petroleum ether and recrystallized from THF:petroleum ether 1:1 (v/v) three times at 0 2C to give the desired product as crystalline solid (5.2 g, 35 percent). 1H NMR (400 MHz, CDCI3, 5, ppm): 7.40-7.31 (m, 5H, CHaromatic), 6.59 (s, 1H, NH), 5.13 (s, 2H, CH2O), 4.38 (ddd, J = 6.5, 5.4, 0.8 Hz, 1H, OCCHNH), 2.59 (t, J = 6.9 Hz, 2H, O(O)CCH2), 2.31-2.06 (m, 2H, CH2). 13C NMR (101 MHz,CDCI3, 5, ppm): 172.5, 169.5, 151.9, 135.3, 128.8, 128.7, 128.5, 67.2, 57.0, 30.0, 27.0. FT-IR: 1651,1737, 1790, 1856 and 1965 cm.
8.25 g
Inert atmosphere
Under a dry inert gas condition, 10 g of γ-benzyl-L-glutamic acid were added into 100 ml of anhydrous tetrahydrofuran, and reacted with 6.5 g of triphosgene. Petroleum ether was then added for sedimentating, to obtain a solid. After recrystallization and drying, 8.25 g of γ-benzyl-L-glutamic acid-N-carboxylic acid anhydride (BLG-NCA) monomer were finally obtained. Under an inert gas condition, a solution of n-hexyl amine in dimethyl formamide (DMF) was added into a solution of BLG-NCA in DMF, wherein the molar ratio between n-hexyl amine and γ-benzyl-L-glutamic acid-N-carboxylic acid anhydride (BLG-NCA) was 1:50. After the reaction, diethyl ether was added for sedimentating, to obtain a solid after filtration. After drying, a glutamic acid copolymer having a benzyl protecting group and a polymerization degree of 50 was obtained. After the protecting group was removed, a glutamic acid copolymer having a structure of formula (II) and a polymerization degree of 50 was obtained, denoted as P(Glu)50.
5.68 g
at 50℃; for 0.5 h; Inert atmosphere; Schlenk technique
Weighed 6.0 g (22.0 mmol) of γ-benzyl-L-glutamic acid (H-Glu (OBzl) -OH) and 2.6 g (8.8 mmol) of triphosgene (BTC) were added to a Schlenk Bottle, 150 mL of THF was added under nitrogen (the solvent was about 1.0 g of H-Glu (OBzl) -OH / 25 mL of THF). The reaction was stirred in an oil bath at 50 ° C until the solution became clear and clear (yellow) half an hour. The reaction solution was rapidly transferred to a one-necked flask and the solvent THF was removed by steaming. The reaction flask was sealed and transferred to a glove box and recrystallized twice with n-hexane / THF (V / V = 3/1). The resulting crystals were dried in vacuo, sealed and stored at -20 ° C. A needle-like crystal of 5.86 g was obtained as BLG-NCA.
Reference：
[1] RSC Advances, 2016, vol. 6, # 8, p. 6368 - 6377
[2] Chemical Communications, 2015, vol. 51, # 86, p. 15645 - 15648
[3] Journal of Polymer Science, Part A: Polymer Chemistry, 2013, vol. 51, # 24, p. 5270 - 5279
[4] Soft Matter, 2013, vol. 9, # 16, p. 4304 - 4311
[5] Journal of the American Chemical Society, 2015, vol. 137, # 23, p. 7286 - 7289
[6] Molecules, 2014, vol. 19, # 12, p. 19751 - 19768
[7] Molecular Crystals and Liquid Crystals, 2007, vol. 464, # 1, p. 211 - 216
[8] Journal of Materials Chemistry B, 2013, vol. 1, # 38, p. 5114 - 5127
[9] Biomacromolecules, 2013, vol. 14, # 10, p. 3793 - 3799
[10] Chemical Communications, 2014, vol. 50, # 35, p. 4571 - 4574
[11] Chemical Communications, 2014, vol. 50, # 50, p. 6592 - 6595
[12] Macromolecules, 2014, vol. 47, # 21, p. 7272 - 7283
[13] Journal of the American Chemical Society, 2007, vol. 129, # 46, p. 14114 - 14115
[14] Journal of Polymer Science, Part A: Polymer Chemistry, 2012, vol. 50, # 6, p. 1076 - 1085
[15] Journal of Polymer Science, Part A: Polymer Chemistry, 2012, vol. 50, # 15, p. 3016 - 3029
[16] Journal of Polymer Science, Part A: Polymer Chemistry, 2012, vol. 50, # 18, p. 3743 - 3749
[17] Chemical Communications, 2016, vol. 52, # 75, p. 11251 - 11254
[18] Patent: US2016/74524, 2016, A1, . Location in patent: Paragraph 0046; 0047
[19] Chemistry - A European Journal, 2004, vol. 10, # 16, p. 4000 - 4010
[20] Journal of Controlled Release, 2012, vol. 161, # 1, p. 124 - 131
[21] Reactive and Functional Polymers, 2016, vol. 100, p. 173 - 180
[22] Journal of Polymer Science, Part A: Polymer Chemistry, 2013, vol. 51, # 19, p. 4175 - 4182
[23] Macromolecular Bioscience, 2014, vol. 15, # 1, p. 138 - 145
[24] Carbohydrate Polymers, 2012, vol. 89, # 4, p. 1207 - 1214
[25] Synthetic Communications, 1999, vol. 29, # 5, p. 843 - 854
[26] Journal of the American Chemical Society, 2012, vol. 134, # 45, p. 18542 - 18545
[27] Science China Chemistry, 2018, vol. 61, # 10, p. 1314 - 1319
[28] Biomacromolecules, 2017, vol. 18, # 10, p. 3367 - 3374
[29] Chemistry - An Asian Journal, 2014, vol. 9, # 10, p. 2850 - 2858
[30] Patent: WO2018/20034, 2018, A1, . Location in patent: Page/Page column 22
[31] Journal of the American Chemical Society, 2007, vol. 129, # 49, p. 15364 - 15371
[32] Journal of the American Chemical Society, 2010, vol. 132, # 7, p. 2370 - 2377
[33] Chemical Communications, 2011, vol. 47, # 22, p. 6245 - 6247
[34] Chemistry - A European Journal, 2012, vol. 18, # 8, p. 2297 - 2304
[35] Macromolecules, 2011, vol. 44, # 18, p. 7315 - 7326
[36] Journal of Polymer Science, Part A: Polymer Chemistry, 2014, vol. 52, # 2, p. 248 - 257
[37] Journal of Controlled Release, 2013, vol. 171, # 3, p. 339 - 348
[38] Journal of Polymer Science, Part A: Polymer Chemistry, 2014, vol. 52, # 9, p. 1228 - 1236
[39] Molecules, 2014, vol. 19, # 8, p. 11915 - 11932
[40] RSC Advances, 2015, vol. 5, # 19, p. 14482 - 14491
[41] Polymer, 2015, vol. 70, p. 183 - 193
[42] Patent: US2015/231273, 2015, A1, . Location in patent: Paragraph 0101
[43] Polymer, 2015, vol. 80, p. 188 - 204
[44] Biomacromolecules, 2015, vol. 16, # 11, p. 3455 - 3465
[45] International Journal of Pharmaceutics, 2016, vol. 505, # 1-2, p. 24 - 34
[46] International Journal of Nanomedicine, 2016, vol. 11, p. 1717 - 1730
[47] Patent: CN106580920, 2017, A, . Location in patent: Paragraph 0059; 0060
[48] Patent: WO2017/145164, 2017, A1, . Location in patent: Page/Page column 73
[49] Biomacromolecules, 2018, vol. 19, # 6, p. 2062 - 2071
4
[ 75-44-5 ]
[ 1676-73-9 ]
[ 3190-71-4 ]
Yield
Reaction Conditions
Operation in experiment
95.4%
at 50℃; for 1 h;
Example 8 L-benzylglutamate NCA Vacuum-dried H-Glu(OBn)-OH (71.2 g, 300.0 mmol) was suspended in 900 mL of anhydrous THF. Phosgene (20percent in toluene) (210 mL, 420 mmol) was added to the amino acid suspension at room temperature and after ten minutes, the mixture was heated to 50° C. The amino acid dissolved over the course of approx. 1 hr, forming a clear solution. The solution was slightly cooled and concentrated on the rotovap. Fresh anhydrous THF (400 mL) was added to the residue and the solution was re-evaporated on the rotovap to give a colorless solid, which was dissolved in 300 mL anhydrous THF, transferred to a 4 L beaker and precipitated by the slow addition of 1.5 L of anhydrous heptane.The pure NCA was isolated by suction filtration and dried in vacuo. 75.31 g (95.4percent yield) of Glu(OBn) NCA was isolated as a colorless, crystalline solid. 1H NMR (CDCl3) δ 7.36 (5H), 6.40 (1H), 5.14 (2H), 4.40 (1H), 2.60 (2H), 2.22 (2H).
95.4%
at 50℃; for 1.16 h;
Vacuum-dried H-Glu(OBn)-OH (71.2 g, 300.0 mmol) was suspended in 900 mE of anhydrous THF. Phosgene (20percent in toluene) (210 mE, 420 mmol) was added to the amino acid suspension at room temperature and afier ten minutes, the mixture was heated to 50° C. The amino acid dissolved over the course of approx. 1 hr, forming a clear solution. The solution was slightly cooled and concentratedthe rotovap. Fresh anhydrous THF (400 mE) was added to the residue and the solution was re-evaporated on the rotovapgive a colorless solid, which was dissolved in 300 mE anhydrous THF, transferred to a 4 E beaker and precipitatedthe slow addition of 1.5 E of anhydrous heptane. The pure NCA was isolated by suction filtration and dried in vacuo. 75.31 g (95.4percent yield) of Glu(OBn) NCA was isolated as a colorless, crystalline solid. ‘H NMR (CDC13) ö 7.36 (5H), 6.40 (1H), 5.14 (2H), 4.40 (1H), 2.60 (2H), 2.22 (2H).
90%
at 50℃; for 0.5 h;
HO-Glu(Bzl)-NH2 (30.0 g, 126.0 mmol) was suspended in 300 mL of anhydrous THF and heated to 50° C. Phosgene (20percent in toluene) (81.3 mL, 164.6 mmol) was added to the amino acid suspension by syringe, and the amino acid dissolved over the course of approx. 30 minutes, forming a clear solution. The solution was concentrated by rotory evaporation, dissolved in 150 mL of anhydrous THF, and transferred to an Erlenmeyer flask. Hexane was added and the product was allowed to crystallize overnight. The NCA was isolated by filtration and dried in vacuo. 29.8 g (90percent yield) of Glu(Bzl) NCA was isolated as a white, crystalline solid. 1H NMR (CDCl3) δ 7.36 (5H), 6.22 (1H), 5.14 (2H), 4.35 (1H), 2.61 (2H), 2.29 (1H), 2.14 (1H) ppm.
Reference：
[1] Patent: US2013/280306, 2013, A1, . Location in patent: Paragraph 0394; 0395
[2] Patent: US2014/271885, 2014, A1, . Location in patent: Paragraph 0363; 0364; 0365
[3] Patent: US2008/274173, 2008, A1, . Location in patent: Page/Page column 94
[4] Molecular Crystals and Liquid Crystals Science and Technology, Section A: Molecular Crystals and Liquid Crystals, 1993, vol. 237, p. 9 - 24
[5] Chemistry - A European Journal, 2009, vol. 15, # 1, p. 254 - 260
[6] Nippon Kagaku Zasshi, 1956, vol. 77, p. 44,46[7] Chem.Abstr., 1958, p. 258
[8] Journal of the American Chemical Society, 1956, vol. 78, p. 941,944
[9] Journal of the American Chemical Society, 1958, vol. 80, p. 3941,3943
[10] Bulletin of the Chemical Society of Japan, 1956, vol. 29, p. 654,658[11] Chem.Abstr., 1958, p. 258
[12] Angewandte Chemie, 1980, vol. 92, # 11, p. 968 - 969
[13] Biomacromolecules, 2010, vol. 11, # 12, p. 3668 - 3672
5
[ 463-71-8 ]
[ 1676-73-9 ]
[ 3190-71-4 ]
Yield
Reaction Conditions
Operation in experiment
73%
at 50℃; for 2 h; Inert atmosphere
10 g of L-glutamic acid-benzyl ester and 6.255 g of triphosgene were mixed with 100 mL of anhydrous tetrahydrofuran. The reaction was carried out under nitrogen atmosphere at 50° C. After 2 hours and the reaction has completed, the above solution was introduced to hexane, and the mixture was recrystallized twice using 1:1 hexane/ ethyl acetate as a recrystallization solvent, resulting in benzyl-L-glutamic acid-N-carboxy anhydride (BLG-NCA). The yield was 73percent. The 1H NMR (500 MHz, CDCl3) measurement result of the BLG-NCA obtained above is shown in FIG. 1
Reference：
[1] Journal of Organic Chemistry, 1992, vol. 57, # 9, p. 2755 - 2756
8
[ 56-86-0 ]
[ 3190-71-4 ]
Reference：
[1] Nippon Kagaku Zasshi, 1956, vol. 77, p. 44,46[2] Chem.Abstr., 1958, p. 258
[3] Bulletin of the Chemical Society of Japan, 1956, vol. 29, p. 654,658[4] Chem.Abstr., 1958, p. 258
[5] Journal of the Chemical Society, 1950, p. 3239,3243
9
[ 100-51-6 ]
[ 3190-71-4 ]
Reference：
[1] Nippon Kagaku Zasshi, 1956, vol. 77, p. 44,46[2] Chem.Abstr., 1958, p. 258
[3] Bulletin of the Chemical Society of Japan, 1956, vol. 29, p. 654,658[4] Chem.Abstr., 1958, p. 258
[5] Journal of the Chemical Society, 1950, p. 3239,3243
10
[ 5680-86-4 ]
[ 3190-71-4 ]
Reference：
[1] Journal of the Chemical Society, 1950, p. 3239,3243
With phosgene; In tetrahydrofuran; at 45 - 65℃; for 1.08333h;
EXAMPLE 2: PREPARATION OF L-GLUTAMIC ACID N-CARBOXYANHYDRIDE, y-BENZYL ESTER.; [0031] In this Example, a stirred mixture of 3.3 liters anhydrous tetrahydrofuran and 466 g (1.96 moles) L-glutamic acid, gamma-benzyl ester, was purged with nitrogen below liquid surface at 0.5 liters/min and heated to 45C over 30 minutes. The nitrogen purge was increased to 2 liters/min and 389 g (3.93 moles) gaseous phosgene was added at a rate to maintain a reaction mixture temperature of 50-65C over 10 minutes. The phosgene was refluxed back into the reaction vessel using a dry ice/acetone reflux condenser. After the phosgene was added, the reaction mixture was heated at 50-65C for 25 minutes until the solids disappeared and a clear solution resulted. The dry ice and acetone were removed from the reflux condenser and the reaction mixture was purged with nitrogen at 4 liters/min and 50-65C for 30 minutes. The tetrahydrofuran and excess phosgene were removed by vacuum stripping at50-65C down to 15 mm Hg whereupon the concentrated residue crystallized. EPO <DP n="15"/>The stripped residue was dissolved in 2.8 liters anhydrous ethyl acetate and the cloudy mixture vacuum filtered to remove insoluble solids. Anhydrous hexanes (5.5 liters) were added gradually with stirring to the filtrate to crystallize the product. The product slurry was stirred for 30 minutes and refrigerated at 5C overnight. The product was isolated by vacuum filtration under a nitrogen blanket, washed with a 0.93 liter solution of 3:1 , hexanes.ethyl acetate and with 1.4 liters hexanes, dried in the funnel by pulling vacuum on it for 30 minutes while maintaining a positive nitrogen purge and vacuum dried at room temperature to a constant weight. After drying, 461 g (89.2% yield) L-glutamic acid N-carboxyanhydride, gamma-benzyl ester were produced with a melting point of92-94C and a chloride content of 0.022%.
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), Mn = 5700, DP = 11 (determined by 1H NMR) and 25 (determined by size-exclusion chromatography), Mw/Mn = 1.24, helix content = 42 percent in DMSO and 53 percent in DMF[ No CAS ]
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), Mn = 2800, DP = 3 (determined by 1H NMR) and 12 (determined by size-exclusion chromatography), Mw/Mn = 1.53[ No CAS ]
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), Mn = 7000, DP = 16 (determined by 1H NMR) and DP = 31 (determined by size-exclusion chromatography), Mw/Mn = 1.12, helix content = 58 percent in DMSO and 79 percent in DMF[ No CAS ]
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), DP = 5 (determined by 1H NMR)[ No CAS ]
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), Mn = 7600, DP = 20 (determined by 1H NMR) and 34 (determined by size-exclusion chromatography), Mw/Mn = 1.09, helix content = 67 percent in DMSO and 81 percent in DMF[ No CAS ]
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), DP = 5 (determined by 1H NMR)[ No CAS ]
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), Mn = 7900, DP = 26 (determined by 1H NMR) and 35 (determined by size-exclusion chromatography), Mw/Mn = 1.07, helix content = 74 percent in DMSO and 87 percent in DMF[ No CAS ]
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), Mn = 4400, DP = 7 (determined by 1H NMR) and 20 (determined by size-exclusion chromatography), Mw/Mn = 1.13[ No CAS ]
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), Mn = 8500, DP = 34 (determined by 1H NMR) and 38 (determined by size-exclusion chromatography), Mw/Mn = 1.06, helix content = 82 percent in DMSO and 90 percent in DMF[ No CAS ]
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), Mn = 5900, DP = 10 (determined by 1H NMR and 26 (determined by size-exclusion chromatography), Mw/Mn = 1.15, helix content = 45 percent[ No CAS ]
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), Mn = 9800, DP = 57 (determined by 1H NMR) and 44 (determined by size-exclusion chromatography), Mw/Mn = 1.05, helix content = 90 percent in DMSO and 96 percent in DMF[ No CAS ]
4-(L-alanylamino)phenylacetylene-terminated poly(γ-benzyl-L-glutamate), Mn = 7900, DP = 21 (determined by 1H NMR) and 36 (determined by size-exclusion chromatography), Mw/Mn = 1.14, helix content = 72 percent[ No CAS ]
L-leucine-poly(γ-benzyl L-glutamate)-CH2CH2-O-CO-CMe2Br, Pn = 110, atom transfer radical polymerization; monomer(s): alloc-L-leucine-α-bromo-isobutyric acid 2-aminoethanol ester; γ-benzyl L-glutamate-N-carboxyanhydride[ No CAS ]
L-leucine-poly(γ-benzyl L-glutamate)-CH2CH2-O-CO-CMe2Br, Pn = 167, atom transfer radical polymerization; monomer(s): alloc-L-leucine-α-bromo-isobutyric acid 2-aminoethanol ester; γ-benzyl L-glutamate-N-carboxyanhydride[ No CAS ]
L-leucine-poly(γ-benzyl L-glutamate)-CH2CH2-O-CO-CMe2Br, Pn = 205, atom transfer radical polymerization; monomer(s): alloc-L-leucine-α-bromo-isobutyric acid 2-aminoethanol ester; γ-benzyl L-glutamate-N-carboxyanhydride[ No CAS ]
L-leucine-poly(γ-benzyl L-glutamate)-CH2CH2-O-CO-CMe2Br, Pn = 94, atom transfer radical polymerization; monomer(s): alloc-L-leucine-α-bromo-isobutyric acid 2-aminoethanol ester; γ-benzyl L-glutamate-N-carboxyanhydride[ No CAS ]
L-leucine-poly(γ-benzyl L-glutamate)-CH2CH2-O-CO-CMe2Br, Pn = 304, atom transfer radical polymerization; monomer(s): alloc-L-leucine-α-bromo-isobutyric acid 2-aminoethanol ester; γ-benzyl L-glutamate-N-carboxyanhydride[ No CAS ]
poly[(ethylene oxide)-r-(propylene oxide)], α-(2-aminoethyl)-terminated, ω-methyl-terminated, Mn 1010 Da, Mw/Mn 1.05, average 19 ethylene oxide-derived units and 3 propylene oxide-derived units[ No CAS ]
[ 3190-71-4 ]
poly[(ethylene oxide)-r-(propylene oxide)]-b-poly(γ-benzyl-L-glutamate N-carboxyanhydride), Mn 20100 Da, Mw/Mn 1.38, peptide block DP value 87 by GPC and 78 by NMR, average 19 ethylene oxide-derived units and 3 propylene oxide-derived units[ No CAS ]
poly[(ethylene oxide)-r-(propylene oxide)], α-(2-aminoethyl)-terminated, ω-methyl-terminated, Mn 1010 Da, Mw/Mn 1.05, average 19 ethylene oxide-derived units and 3 propylene oxide-derived units[ No CAS ]
[ 3190-71-4 ]
poly[(ethylene oxide)-r-(propylene oxide)]-b-poly(γ-benzyl-L-glutamate N-carboxyanhydride), Mn 10450 Da, Mw/Mn 1.35, peptide block DP value 43 by GPC and 39 by NMR, average 19 ethylene oxide-derived units and 3 propylene oxide-derived units[ No CAS ]
poly[(ethylene oxide)-r-(propylene oxide)], α-(2-aminoethyl)-terminated, ω-methyl-terminated, Mn 1010 Da, Mw/Mn 1.05, average 19 ethylene oxide-derived units and 3 propylene oxide-derived units[ No CAS ]
[ 3190-71-4 ]
poly[(ethylene oxide)-r-(propylene oxide)]-b-poly(γ-benzyl-L-glutamate N-carboxyanhydride), Mn 7130 Da, Mw/Mn 1.18, peptide block DP value 28 by GPC and 21 by NMR, average 19 ethylene oxide-derived units and 3 propylene oxide-derived units[ No CAS ]
copolymer, Mn = 29450 g/mol, PDI (Mw/Mn) = 1.18, degree of polymerization = 30 amino acid units in the PBLG block (1H NMR), critical gelation conc. = 2.9 wt%, gel-solution temp. = 41 deg C, width of the ribbon formed in toluene (SAXS) = 5.5 nm[ No CAS ]
copolymer, Mn = 43100 g/mol, PDI (Mw/Mn) = 1.18, degree of polymerization = 43 amino acid units in the PBLG block (1H NMR), critical gelation conc. = 1.8 wt%, gel-solution temp. = 49 deg C, width of the ribbon formed in toluene (SAXS) = 7.1 nm[ No CAS ]
copolymer, Mn = 48900 g/mol, PDI (Mw/Mn) = 1.21, degree of polymerization = 78 amino acid units in the PBLG block (1H NMR), critical gelation conc. = 0.3 wt%, gel-solution temp. = 52 deg C, width of the ribbon formed in toluene (1H NMR) = 11.7 nm[ No CAS ]
name: poly(γ-benzyl-L-glutamate)-block-poly(ε-Cbz-L-lysine), Mn=44600, Mw/Mn=1.03; monomer(s): (S)-ε-carbobenzoxy-lysine-N-carboxyanhydride, (S)-γ-benzyl-L-glutamate-N-carboxyanhydride[ No CAS ]
In DMF (N,N-dimethyl-formamide); at 20℃; for 120h;
Example 2Preparation of Star-shaped Fluorescent Polypeptides1. Polymerization ExperimentsA solution of the corresponding alpha-amino acid N-carboxyanhydride in dry DMF (about 0.2 g/ml) was introduced into a Schlenk flask provided with a drying tube. The alpha-amino acid N-carboxyanhydrides gamma-benzyl-L-glutamate N-carboxyanhydride (Bn-Glu NCA) and epsilon-benzyloxycarbonyl-L-lysine N-carboxyanhydride (Z-Lys NCA) used were synthesized by the procedure described by Poche et al., Syn. Commun. 29 (1999), 843. A solution of the above-obtained compound N,N'-bis(2,6-diisopropylphenyl)-1,6,7,12-tetra[4-(2-aminoethyl)phenoxy]perylene-3,4,9,10-tetracarboxylic acid diimide in dry DMF was then added to the Schlenk flask, and the reaction mixture was stirred at room temperature. The amount of initiator solution depended on the desired arm length of the star polymer, which was controlled via the molar ratio of alpha-amino acid N-carboxyanhydride and initiator N,N'-bis-(2,6-diisopropylphenyl)-1,6,7,12-tetra[4-(2-aminoethyl)phenoxy]perylene-3,4,9,10-tetracarboxylic acid diimide. After 5 days, the solution was slowly added to a 20-fold (vol/vol) excess of diethyl ether. The precipitated polymer was filtered off and vacuum-dried.Poly(gamma-benzyl-L-glutamate) star polymer (I):1H-NMR (500 MHz, C2D2Cl4): delta=8.23 (s, 4H; perylene), 7.25 (b, 6H+5H×4n; Ph-H+Bn-H), 7.02 (b, 8H; Ph-H), 6.89 (b, 8H; Ph-H), 5.0 (s, 2H×4n; Bn-CH2-), 4.0 (b, 1H×4n; Calpha-H), 2.30 (b, 4H×4n; -CH2CH2-), 1.05 (b, 24H; -CH3 isopropyl)Poly(epsilon-benzyloxycarbonyl-L-lysine) star polymer (II):1H-NMR (500 MHz, C2D2Cl4): delta=7.25 (b, 5H×4n; Bn-H), 5.0 (b, 2H×4n; Bn-CH2-), 3.90 (b, 1H×4n; Calpha-H), 3.10 (b, 2H×4n; -CH2NH-), 2.0 (b, 2H×4n; -CH2-), 1.50 (b, 4H×4n; -CH2CH2-), 1.05 (b, 24H, CH3 isopropyl)n indicates the average number of monomer units per arm.
Chemistry
Pharmaceutical Intermediates
Inhibitors/Agonists
Material Science
Life Science
For Research Only
100K+ Compounds
Competitive Price
1-2 Day Shipping
