GB964990A - Phenylanlanine derivatives - Google Patents

Abstract

The invention comprises compounds of the formula: <FORM:0964990/C1/1> (wherein R1 and R* are hydrogen atoms or alkyl groups, R11 is an alkyl group of at most 5 carbon atoms and R and R DEG are hydrogen atoms or alkanoyl groups of at most 6 carbon atoms, but R cannot be alkanoyl when R DEG is hydrogen) and non-toxic acid addition salts thereof; and their preparation by (1) heating a ketone of the formula: <FORM:0964990/C1/2> with ammonium carbonate and a water-soluble cyanide to produce a hydantoin of the formula: <FORM:0964990/C1/3> and contacting this with a strong inorganic base to give a trimethoxyphenylalaine compound of the formula: <FORM:0964990/C1/4> or (2) heating a ketone of the above formula with ammonium chloride and a water-soluble cyanide to produce a nitrile of the formula: <FORM:0964990/C1/5> and treating this with a strong acid to give trimethoxyphenylalanine compound which is then demethylated by heating with a strong solution of a hydrohalic acid to give a trihydroxyphenylalanine, which may then be esterified by heating with an alkanol in the presence of a mineral acid catalyst and/or acylated with an alkanoyl halide or an alkanoic anhydride. L-isomers of compounds of the first general formula above, which are claimed in Specification 963,074, are disclaimed. The 0,0,0-triacyl compounds are prepared by a modified Schotten-Baumann reaction while the 0,0,0,N-tetra-acyl compounds are prepared by use of excess of acylating agent. Examples are given. Ketones of the formula II are prepared by the processes: <FORM:0964990/C1/6>ALSO:Soaps are stabilized by the addition of anti-oxidants of the formula <FORM:0964990/C4-C5/1> wherein R1 and R* are hydrogen atoms or alkyl groups, R11 is an alkyl group of at most 5 carbon atoms, and R and R DEG are hydrogen atoms or alkanoyl groups of at most 6 carbon atoms, but R cannot be alkanoyl when R DEG is hydrogen. Specification 936,074 is referred to.ALSO:Pharmaceutical compositions, suitable for oral or parenteral administration, comprise phenylalanine derivatives of the formula <FORM:0964990/A5-A6/1> (wherein R1 and R* are hydrogen atoms or alkyl groups, R11 is an alkyl group of at most 5 carbon atoms, and R and R DEG are hydrogen atoms or alkanoyl groups of at most 6 carbon atoms, but R cannot be alkanoyl when R DEG is hydrogen) or acid-addition salts thereof, and suitable carriers. They are anti-hypertensives, and may contain other anti-hypertensive agents. Specification 936,074 is referred to.