oil analysis calc 39 d for c 35 h 31 n 2 o 5 p c 70 69 h 5 93 n 4 71 p 5 21 found c 70 55 h 5 98 n 4 65 p 5 28 n 2 phenylethyl phenylmethoxy phosphinyl acetyl l tryptophan phenylmethyl ester 3 3 g see example 6 was dissolved in methanol and lithium hydroxide monohydrate 0 466 g dissolved in a little water was added the mixture was stirred at room temperature for 2 hours 10 palladium on charcoal 1 g was added and the mixture hydrogenated at 1 atmosphere for 2 hours the catalyst was filtered off through celite and the filtrate evaporated to dryness the residue was dissolved in water passed through a millipore filter and lyophilized yielding 2 1 g of product melting point gt 350 u00b0 c u03b1 rt d 3 9 u00b0 1 h 2 o analysis calc 39 d for c 21 h 21 n 2 o 5 pli 2 3h 2 o c 52 51 h 5 67 n 5 83 p 6 45 li 2 89 found c 52 44 h 5 03 n 5 64 p 6 40 li 3 1 electrophoresis showed this material to have two components it 300 mg was chromatographed on deae sephadex 60 ml oh form ph 7 4 eluted with a nh 4 hco 3 gradient 0 005 to 0 5 m pure fractions one component by electrophoresis were combined and evaporated the residue was dissolved in water millipore filtered and lyophilized two times yielding 0 29 g of product u03b1 rt d 3 u00b0 0 5 h 2 o analysis calc 39 d for c 21 h 23 n 2 o 5.