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 this phase was 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 thus obtained product (3.0 m mole) was dissolved in ethanol (15 ml) and L-arginine (0.58 g, 3.0 m mole) water (5 ml) solution was added thereto. The solvent was evaporated and water was added thereto, and 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 spots respectively in Rf =0.8 for peptides in the free form and Rf =0.25 for arginine by a 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 a hydrolysis of the product with 6N hydrochloric acid, and amino acids were analyzed. Methionine:Proline:Arginine=1.00:2.03:0.95.

Provenance & Evidence