| Identification | More | [Name]
L-Valine benzyl ester 4-toluenesulfonate | [CAS]
16652-76-9 | [Synonyms]
BENZYL L-VALINATE P-TOLUENESULFONATE
H-VAL-OBZL P-TOSYLATE
H-VAL-OBZL TOS
H-VAL-OBZL TOS-OH
L-VALINE BENZYL ESTER 4-TOLUENESULFONATE SALT
L-VALINE BENZYL ESTER P-TOLUENESULFONATE
L-VALINE BENZYL ESTER P-TOLUENESULFONATE SALT
L-VALINE BENZYL ESTER-P-TOSYLATE
L-VALINE-BENZYL ESTER P-TOSYLATE SALT
L-VALINE BENZYL ESTER TOLUENE-4-SULFONATE
L-VALINE BENZYL ESTER TOSYLATE
L-VALLINE BENZYL ESTER P-TOLUENESULFONATE SALT
VALINE-OBZL P-TOSYLATE
L-valine benzyl ester P-*toluenesulfonate crystal
O-benzyl-L-valine toluene-p-sulphonate
L-Valine benzyl ester 4-toluenesulfonate
Val-OBzl Tosoh
L-VALINE BENZYL ESTER P-*TOLUENESULFONAT E CRYSTALLI
VAL-OBZL.TOS
L-Valine benzyl ester p-toluenesulfonat salt | [EINECS(EC#)]
240-702-6 | [Molecular Formula]
C19H25NO5S | [MDL Number]
MFCD00038908 | [Molecular Weight]
379.47 | [MOL File]
16652-76-9.mol |
| Chemical Properties | Back Directory | [Appearance]
Crystalline | [Melting point ]
160-162 °C | [alpha ]
-3.7 º (c=3.2% in methanol) | [Boiling point ]
160-162°C | [Fp ]
160-162°C | [storage temp. ]
−20°C
| [solubility ]
Soluble in Chloroform,Dichloromethane,Ethyl Acetate,DMSO,Acetone,etc. | [form ]
Powder | [Optical Rotation]
[α]20/D 3.7±0.3°, c = 3.2% in methanol | [BRN ]
3643436 | [Major Application]
peptide synthesis | [InChI]
InChI=1/C12H17NO2.C7H8O3S/c1-9(2)11(13)12(14)15-8-10-6-4-3-5-7-10;1-6-2-4-7(5-3-6)11(8,9)10/h3-7,9,11H,8,13H2,1-2H3;2-5H,1H3,(H,8,9,10)/t11-;/s3 | [InChIKey]
QWUQVUDPBXFOKF-XAAIUDFWNA-N | [SMILES]
C1(=CC=CC=C1)COC([C@@H](N)C(C)C)=O.C1(S(=O)(=O)O)C=CC(C)=CC=1 |&1:9,r| | [CAS DataBase Reference]
16652-76-9(CAS DataBase Reference) |
| Safety Data | Back Directory | [Safety Statements ]
S22:Do not breathe dust .
S24/25:Avoid contact with skin and eyes . | [WGK Germany ]
3
| [Storage Class]
13 - Non Combustible Solids |
| Hazard Information | Back Directory | [Chemical Properties]
Crystalline | [Uses]
Val-OBzl TosOH is a L-Valine derivative useful as intermediate for the preparation of peptides. | [reaction suitability]
reaction type: solution phase peptide synthesis | [Synthesis]
GENERAL STEPS: The esterification reaction was carried out on L-amino acids, except phenylglycine, where the D-enantiomer was used. A mixture of L-valine (0.05 mol), 4-methylbenzenesulfonic acid (0.06 mol), benzyl alcohol (0.25 mol), and cyclohexane (30 mL) was refluxed for 4 hours using a Dean-Stark apparatus to separate the water with which it formed an azeotrope. After cooling the reaction mixture to room temperature, ethyl acetate (80 mL) was added. After stirring for 1 hour, the precipitate was collected by filtration and dried to give L-valyl benzyl ester p-toluenesulfonate as a white solid. Following this method, amino acids 1-6 were converted to the corresponding benzyl p-toluenesulfonate 1a-6a. benzylation of compound 7 was carried out in the same manner but in the presence of more 4-methylbenzenesulfonic acid (0.11 mol) to give di-p-toluenesulfonate 7a as a white solid. The p-toluenesulfonate 8a separated as an oil at the end of the reaction; instead of adding ethyl acetate, the supernatant was removed, the oil phase was washed with cyclohexane, and poured into an aqueous solution of dichloromethane/Na2CO3. After separation of the aqueous layer, the dichloromethane was evaporated and the residue was treated with methanol hydrochloride to give the corresponding hydrochloride salt as a white solid. The benzylation of compound 9 was prolonged overnight and at the end of the reaction, 9a separated as an oil, which was poured into dichloromethane/water. After removal of the organic layer, the aqueous phase was alkalized with NaHCO3 and extracted with ethyl acetate. The organic extract was concentrated to a small volume and a slight excess of 4-methylbenzenesulfonic acid was added to precipitate 9a as a white crystalline solid. | [References]
[1] Tetrahedron Letters, 2008, vol. 49, # 49, p. 6962 - 6964
[2] Journal of the Indian Chemical Society, 2001, vol. 78, # 3, p. 137 - 141
[3] Amino Acids, 2017, vol. 49, # 5, p. 965 - 974
[4] Chirality, 2012, vol. 24, # 2, p. 188 - 192
[5] European Journal of Medicinal Chemistry, 2018, vol. 157, p. 962 - 977 |
|
|