Tyrosine is enerally proposed as the initial precursor i n the biogenesis of epinephrine an$ norepinephrine. Methods are presented for the pre aration of amino acids which could be included in alternate mechanisms or possihy interfere with the metabolic sequence. During the course of this study the following compounds were prepared: phenylserine and its ethyl ester, p-hydroxyphenylserine, 0-methyl tyrosine, and w-aminoacetylcatecho1 in a n attempt t o prepare dihydroxyphenylserine, DOPS. An effort was made to improve o n the practicality of the methods previously used. I n some cases a specific adaptation of known procedures was employed; i n others new syntheses were developed.
ECENT STUDIES (1, 2) tend to advance Blaschko's original hypothesis (3) concerning the role of various amino acids in the biogenesis of catecholamines: tyrosine+3,4dihydroxyphenylalanine (DOPA) Ahydroxytyramine (Dopamine)+norepinephrine.
Only a few steps in the classical sequence of reactions have been clearly demonstrated. T h e purpose of this investigation was to prepare, by convenient methods, amino acids related t o those proposed in the biogenetic sequence. T h e amino acids may have functions of their own or serve as intermediates in alternate metabolic pathways leading to the formation of norepinephrine.
Recently, Dickenson and Thompson (4) reported that phenylalanine was necessary for virus synthesis and that L-threophenylserine was the most active of a series of compounds tested against influenza A virus. Holtz, et al. (5), found that all organ extracts which decarboxylated DOPA also attacked the phenylserines.
During the course of this study the following compounds were prepared : phenylserine and its ethyl ester, p-hydroxyphenylserine, 0-methyl tyrosine, and w-aminoacetylcatechol (in a n attempt to prepare dihydroxyphenylserine, DOPS). An effort was mpde to improve on the practicality of the methods previously used.
I n some cases a specific adaptation of known procedures was employed, and in others new syntheses were developed. EXPERIMENTAL
The melting points reported in the paper are uncorrected and were determined by the capillary tube method.
pHydroryphenacy1 Cyanide (II).-In 100 ml. of alcohol was dissolved 21.5 Gm. (0.125 mole) of p-hydroxyphenacyl chloride (6) (Ia), and the solution was warmed to 50". To the warm solution was added, with stirring, 26 Gm. (0.46 mole) potas-