Water → HCID 70040089, compound

Participants

Reaction Steps

Dibenzylphosphoryl-L-methionyl-L-prolyl-L-proline methylester (1.87 g, 3.0 m mole) was dissolved in acetone (18 ml), and 1N sodium hydroxide (4.5 ml) was added thereto under cooling and the mixture was stirred for 4 hours. To the solution, water (100 ml) was added, and the solution was washed with diethyl ether. Ethyl acetate (200 ml) was added thereto and the mixture was adjusted to pH 2 with 1N hydrochloric acid while stirring strongly. The ethyl acetate phase was separated and dried over anhydrous sodium sulfate. The solvent was evaporated to obtain an oily dibenzylphosphoryl-L-methionyl-L-prolyl-L-proline (1.81 g, yield: 99.1%). All of the thus obtained product (3.0 m mole) was dissolved in ethanol (15 ml) and a L-arginine (0.58 g, 3.0 m mole) water (5 ml) solution was added thereto. The solvent was evaporated, water was added thereto, and the thus obtained solution was freeze-dried to obtain dibenzylphosphoryl-L-methionyl-L-prolyl-L-proline L-arginine salt (2.27 g, yield: 98.7% from dibenzylphosphoryl-L-methionyl-L-prolyl-L-proline methylester). This product gave a single spot respectively having a Rf =0.8 for peptides in the free form and an Rf =0.25 for arginine by thin layer chromatography (developing solvent, n-butanol:acetic acid:water=2:1:1, Colour forming method, spraying of 25% hydrobromic acid and 0.1 ninhydrin, and heating). After hydrolysis of the product with 6N hydrochloric acid, the amino acids were analyzed. Methionine:Proline:Arginine=1.00:2.03:0.95.

Provenance & Evidence