HCID 54227244, compound → L-TYROSINE, 3-HYDROXY-, PHENYLMETHYL ESTER

Participants

Reaction Steps

First, carbobenzozyglycyl-3,4-diacetyloxy-L-phenylalanine-benzyl ester was obtained in the manner which follows. Dichloromethane (100 ml) solution containing 0.95 g. (9.4 millimole) of triethylamine was permitted to react with 3.64 g (8.92 millimole) of 3,4-diacetyloxy-L-phenylalanine-benzyl ester hydrochloride for 0.3 hours at room temperature. The solution was then concentrated in vacuo at room temperature to dryness. The residue obtained was filtered and washed with ether to give 1.54 g of triethylamine hydrochloride, contaminated with 3,4-diacetyloxy-L-phenylalanine-benzyl ester in various stages of deprotection. For instance, 3,4-dihydroxy-L-phenylalanine-benzyl ester was obtained quantitatively if a large excess of triethylamine was employed to neutralize the hydrochloride. The ether filtrate was concentrated in vacuo at room temperature. The resulting residue was analyzed by nmr and found to be consistent with the proposed structure, 3,4-diacetyloxy-L-phenylalanine-benzyl ester.

Provenance & Evidence